1,208 results match your criteria Chinese Journal Of Organic Chemistry[Journal]


Organocatalytic Enantioselective Michael Addition between 3-(3-hydroxy-1-pyrazol-1-yl)Oxindole and βNitrostyrene for the Preparation of Chiral Disubstituted Oxindoles.

J Org Chem 2020 Jul 6. Epub 2020 Jul 6.

Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P.R. China.

A new enantioselective Michael addition between 3-(3-hydroxy-1-pyrazol-1-yl)oxindole, a new synthon generated from isatin ,-cyclic azomethine imine 1,3-dipole, and β-nitrostyrene has been disclosed. A series of chiral 3-(3-oxo-2,3-dihydro-1-pyrazol-1-yl) disubstituted oxindoles were obtained in excellent results (up to 97% yield, up to 94% ee) with moderate to good diastereoselectivities (up to 4.3:1 dr). Read More

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http://dx.doi.org/10.1021/acs.joc.9b03337DOI Listing

Ruthenium(II)-Catalyzed C-H Activation of Chromones with Maleimides to Synthesize Succinimide/Maleimide-Containing Chromones.

J Org Chem 2020 Jul 5. Epub 2020 Jul 5.

Chemical Biology Research Center at School of Pharmaceutical Sciences, Wenzhou Medical University, 1210 University Town, Wenzhou, Zhejiang 325035, China.

An efficient route for the coupling of maleimides with chromones at the C5-position has been developed under Ru(II) catalysis. It could provide 1,4-addition products and oxidative Heck-type products by switching additives. Benzoic acid led to the formation of 1,4-addition products under solvent-free conditions, and silver acetate was promoted to the generation of oxidative Heck-type products. Read More

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http://dx.doi.org/10.1021/acs.joc.0c01223DOI Listing

Chemical Synthesis of Fucosylated Chondroitin Sulfate Oligosaccharides.

J Org Chem 2020 Jul 2. Epub 2020 Jul 2.

State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.

Fucosylated chondroitin sulfates (FuCSs) are a unique type of polysaccharides occurring in sea cucumber that show a variety of biological activities. In particular, well-defined FuCS oligosaccharides, consisting of a trisaccharide repeating unit of β-d-GalNAc(4,6-diS)-(1→4)-[α-l-Fuc(2,4-diS)-(1→3)]-β-d-GlcUA, display potent anticoagulant activity via selective inhibition of the intrinsic tenase, which could be developed into anticoagulant drugs without bleeding risk. Herein, we report an effective approach to the synthesis of FuCS oligosaccharides, as demonstrated by the successful elaboration of FuCS tri-, hexa-, and nonasaccharides. Read More

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http://dx.doi.org/10.1021/acs.joc.0c01009DOI Listing

Copper-Catalyzed Three-Component Formal [3 + 1 + 2] Benzannulation for Carbazole and Indole Synthesis.

J Org Chem 2020 Jun 25. Epub 2020 Jun 25.

Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, People's Republic of China.

Three-component formal [3 + 1 + 2] benzannulation reactions of indole-3-carbaldehydes or 1-methyl-pyrrole-2-carbaldehydes with two different molecules of saturated ketones have been successfully developed under Cu-catalyzed and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated conditions. Various unsymmetrically substituted carbazoles and indoles were obtained up to 95% yield. Furthermore, the resulting products exhibit unusual aggregation-induced emission (AIE) properties in the solid state. Read More

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http://dx.doi.org/10.1021/acs.joc.0c01056DOI Listing
June 2020
4.721 Impact Factor

Iron-Catalyzed Oxidative Decarbonylative α-Alkylation of Acyl-Substituted Furans with Aliphatic Aldehydes as the Alkylating Agents.

J Org Chem 2020 Jun 25. Epub 2020 Jun 25.

Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, P. R. China.

A protocol for FeCl-catalyzed oxidative decarbonylative α-alkylation of acyl furans using alkyl aldehydes as the alkylating agents has been developed. This protocol affords α-alkyl-α-acylfurans in moderate to good yields in a practical and sustainable fashion. Mechanistic studies suggest that the reaction proceeds via generation of an alkyl radical from the alkyl aldehyde, addition of the radical to the furan ring, and subsequent rearomatization. Read More

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http://dx.doi.org/10.1021/acs.joc.0c01002DOI Listing

Access to 4-Alkenylated Coumarins via Ruthenium-Catalyzed Olefinic C-H Alkenylation of Coumarins with Modifiable and Removable Directing Groups.

J Org Chem 2020 Jun 24. Epub 2020 Jun 24.

School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221116, Jiangsu, China.

The ruthenium-catalyzed activation of the C4 position of coumarins for coupling with acrylates was described using modifiable ketone as a directing group. The alkenylation reaction provided a direct approach to prepare previously inaccessible 4-alkenylated coumarins with operational simplicity and high atom-economy. This protocol also worked well with coumarin-3-carboxylic acids to unveil a rare instance of a tandem alkenylation/decarboxylation reaction. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00249DOI Listing

Aphananoid A is an Anti-Inflammatory Limonoid with a New 5/6/5 Fused Ring Featuring a C Carbon Skeleton from .

J Org Chem 2020 Jul 17;85(13):8597-8602. Epub 2020 Jun 17.

State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.

Aphananoid A, a limonoid which features a rare C appendage and new 5/6/5 fused-ring framework, was obtained from . The planar structure as well as the absolute configuration was identified based on extensive spectroscopic analysis and electronic circular dichroism calculations. The biogenetic pathway of aphananoid A was also speculated, which arises from the triterpene by the 3,4--7,8--6,8 -7,30- key pattern. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00922DOI Listing

Silver-Mediated Perfluoroalkylation of Terminal Alkynes with Perfluoroalkyl Iodides.

J Org Chem 2020 Jul 22;85(13):8723-8731. Epub 2020 Jun 22.

School of Chemistry and Chemical Engineering, Hefei University of Technology, 193 Tunxi Road, Anhui 230000, People's Republic of China.

The incorporation of a perfluoroalkyl group (R) into drug candidates has become an increasingly important strategy in drug molecule design. In this study, the silver-mediated perfluoroalkylation reaction based on the addition-elimination process of terminal alkynes which was initiated by a perfluoroalkyl radical to form a C(sp)-R bond has been developed. The reaction proceeds under mild conditions using readily available, low-cost perfluoroalkyl iodides as the sources of the R group. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00894DOI Listing

Baphicacanthcusines A-E, Bisindole Alkaloids from the Leaves of (Nees) Bremek.

J Org Chem 2020 Jul 16;85(13):8580-8587. Epub 2020 Jun 16.

Key Laboratory of Structure-Based Drug Design & Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China.

Four pairs of stereoisomeric indole alkaloids, (±)-baphicacanthcusines A-D (), and one new indole alkaloid, baphicacanthcusine E (), together with nine known compounds were identified from the leaves of . (±)- and - possess an unprecedented skeleton in which two indole moieties are bridged by a phenylpropane unit. (±)- represents the first natural dispiro-oxazolidinone bisoxindoles. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00949DOI Listing

Long-Distance Chirality Transfer from P-Ligand to Prochiral Dihydrosilanes via Pd(II) Aryl Iodide Complex in Pd-Catalyzed Silylation of Aryl Iodide: A DFT Study.

J Org Chem 2020 Jun 5. Epub 2020 Jun 5.

Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, and Key Laboratory of Organosilicon Material Technology of Zhejiang Province, Hangzhou Normal University, Hangzhou 311121, P.R. China.

The mechanism of Pd-catalyzed desymmetric monoarylation of dihydrosilanes with aryl iodides in the presence of chiral TADDOL-derived phosphoramidite ligand toward deeper understanding of the stereoselectivity has been investigated using hybrid density functional theory (DFT) methodology. The full catalytic cycle for the favorable reaction pathway, which is initiated by the oxidative addition of aryl iodide to monoligated Pd leading to the silylation product, was calculated. The DFT calculation results indicate that the enantio-discriminating transmetalation between Pd-Ar bond of the Pd(II) aryl iodide complex and Si-H bond of the prochiral dihydrosilane was the enantioselectivity-determining step. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00202DOI Listing

Visible Light-Catalyzed Benzylic C-H Bond Chlorination by a Combination of Organic Dye (Acr-Mes) and -Chlorosuccinimide.

J Org Chem 2020 Jul 7. Epub 2020 Jul 7.

Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing 100190, P. R. China.

By combining "-chlorosuccinimide (NCS)" as the safe chlorine source with "Acr-Mes" as the photocatalyst, we successfully achieved benzylic C-H bond chlorination under visible light irradiation. Furthermore, benzylic chlorides could be converted to benzylic ethers smoothly in a one-pot manner by adding sodium methoxide. This mild and scalable chlorination method worked effectively for diverse toluene derivatives, especially for electron-deficient substrates. Read More

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http://dx.doi.org/10.1021/acs.joc.0c01000DOI Listing

Pd(II)-Catalyzed Direct γ-C(sp)-H Arylation between Free β-Amino Esters and β-Amino Esters and Aryl Iodides Using a Catalytic Transient Directing Group.

J Org Chem 2020 Jun 4;85(12):7683-7693. Epub 2020 Jun 4.

State Key Laboratory of Drug Research and Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China.

Pd(II)-catalyzed direct γ-C(sp)-H arylation coupling with free β-amino esters and β-amino esters using a commercially available catalytic transient directing group has been developed. This approach features high efficiency, broad substrate tolerance, easily accessible starting materials, and mild reaction conditions. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00115DOI Listing

Meroapplanins A-E: Five Meroterpenoids with a 2,3,4,5-Tetrahydropyridine Motif from .

J Org Chem 2020 Jun 27;85(11):7446-7451. Epub 2020 May 27.

Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China.

Meroapplanins A-E (-) with a 2,3,4,5-tetrahydropyridine fragment were isolated from the fruiting bodies of . Their structures were elucidated by comprehensive spectroscopic analyses. Their absolute configurations were established based on the X-ray diffraction, electronic circular dichroism (ECD), and calculated nuclear magnetic resonance (NMR) with DP4+ analysis. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00842DOI Listing
June 2020
4.721 Impact Factor

Synthesis, Structures, and Properties of BN-Dinaphthothiophenes: Influence of B and N Placement on Photophysical Properties and Aromaticity.

J Org Chem 2020 Jun 28;85(12):7877-7883. Epub 2020 May 28.

Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, Tianjin Key Laboratory of Drug Targeting and Bioimaging, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, People's Republic of China.

Substitution of the C═C functionality with the isosteric and isoelectronic B-N moiety has emerged as a powerful way to expand the family of polycyclic aromatic hydrocarbons. In this paper, two types of BN-dinaphthothiophene () derivatives with different B and N substitution patterns were synthesized in short steps from commercially available materials. X-ray crystallographic analysis revealed that and had rigid and planar frameworks. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00541DOI Listing
June 2020
4.721 Impact Factor

Diaza-Crown Ether-Bridged Chiral Diphosphoramidite Ligands: Synthesis and Applications in Asymmetric Catalysis.

J Org Chem 2020 Jun 29;85(12):8176-8184. Epub 2020 May 29.

National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, P. R. China.

A small library of diaza-crown ether-bridged chiral diphosphoramidite ligands was prepared. In the rhodium-catalyzed asymmetric hydrogenation and hydroformylation reactions, these ligands exhibited distinct properties in catalytic activity and/or enantioselectivity. Hydrogenated products with opposite absolute configurations could be obtained in high yields with excellent ee values by utilizing (,)- and (,)-, respectively. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00223DOI Listing

Metal-Free Trifluoroalkylation of Quinoxalin-2(1)-ones with Unactivated Alkenes and Langlois' Reagent.

J Org Chem 2020 Jun 11;85(11):6888-6896. Epub 2020 May 11.

School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong 273165, China.

A KSO-mediated three-component protocol has been developed for the construction of 3-trifluoroalkylated quinoxalin-2(1)-ones under metal-free conditions. The present reaction could be accomplished through the trifluoroalkylation of quinoxalin-2(1)-ones with unactivated alkenes and Langlois' reagent (CFSONa), which provided a highly attractive approach to access a series of biologically important 3-trifluoroalkylated quinoxalin-2(1)-ones. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03505DOI Listing

Synthesis of Branched Monodisperse Oligoethylene Glycols and F MRI-Traceable Biomaterials through Reductive Dimerization of Azides.

J Org Chem 2020 May 7;85(10):6778-6787. Epub 2020 May 7.

Hubei Province Engineering and Technology Research Center for Fluorinated Pharmaceuticals and School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China.

Multifunctionalized and branched M-OEGs represent valuable PEGylation agents, linkers, and scaffolds in biomedicine. However, the tedious synthesis limited their availability and application. We herein present an azide reductive dimerization method for the convenient synthesis of aza-M-OEGs and derivatives, which provides easy access to a variety of multifunctionalized and branched M-OEGs in one step. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00331DOI Listing

Zn-Catalyzed Cyanation of Aryl Iodides.

J Org Chem 2020 May 6;85(10):6471-6477. Epub 2020 May 6.

State Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou 730000, P. R. China.

We report the first example of zinc-catalyzed cyanation of aryl iodides with formamide as the cyanogen source. The transformation was promoted by the bisphosphine Nixantphos ligand. Under optimized conditions, a variety of electron-donating and electron-withdrawing aryl iodides were converted into nitrile products in good to excellent yields. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00269DOI Listing

Chemoselective Hydrosilylation of the α,β-Site Double Bond in α,β- and α,β,γ,δ-Unsaturated Ketones Catalyzed by Macrosteric Borane Promoted by Hexafluoro-2-propanol.

J Org Chem 2020 May 6;85(10):6578-6592. Epub 2020 May 6.

Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, PR China.

The B(CF)-catalyzed chemoselective hydrosilylation of α,β- and α,β,γ,δ-unsaturated ketones into the corresponding non-symmetric ketones in mild reaction conditions is developed. Nearly 55 substrates including those bearing reducible functional groups such as alkynyl, alkenyl, cyano, and aromatic heterocycles are chemoselectively hydrosilylated in good to excellent yields. Isotope-labeling studies revealed that hexafluoro-2-propanol also served as a hydrogen source in the process. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00568DOI Listing

Huperserratines A and B, Two Macrocyclic Alkaloids with an Unusual Skeleton from .

J Org Chem 2020 May 28;85(10):6803-6807. Epub 2020 Apr 28.

State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China.

Huperserratines A () and B (), two alkaloids with an unprecedented 5-aza-bicyclo[10.4.0]hexadecane skeleton and an oxime function, were isolated from . Read More

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http://dx.doi.org/10.1021/acs.joc.0c00623DOI Listing

Chiral Derivatives of 2-Aminotribenzotriquinacene: Synthesis and Optical Resolution.

J Org Chem 2020 May 24;85(10):6478-6488. Epub 2020 Apr 24.

Department of Chemistry and Center for Molecular Materials (CM2), Bielefeld University, 33615 Bielefeld, Germany.

Starting from a hitherto unknown 2-aminotribenzotriquinacene, several 2-amino-3-X-substituted TBTQ derivatives, all bearing a single -difunctionalized indane wing, were synthesized as rigid and chiral building blocks for the potential construction of complex supramolecular architectures. Efficient access to two pairs of enantiomeric TBTQ derivatives, namely, the peripheral -nitroaniline (X = NO) and the related anthranilic acid (X = COH), was developed using chiral auxiliaries as the resolving reagents. The structure of the intermediate diastereomers was confirmed by H and C NMR spectroscopy, high-resolution mass spectroscopy (HRMS), and polarimetry. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00396DOI Listing

Ruthenium-Catalyzed Selectively Oxidative C-H Alkenylation of -Acylated Aryl Sulfonamides by Using Molecular Oxygen as an Oxidant.

J Org Chem 2020 May 20;85(9):5916-5926. Epub 2020 Apr 20.

School of Pharmaceutical Sciences, Tsinghua University, Haidian District, Beijing 100084, China.

A ruthenium-catalyzed sulfonamide-directed aryl C-H alkenylation/annulation to afford five-membered sultam by using of molecular oxygen as an oxidant is reported in this article. Compared to the previous transition-metal-catalyzed C-H alkenylation of aryl sulfonamides, no excess metal salt oxidant was required in this method. A wide sulfonamide substrates scope and good regioselectivity and site-selectivity make this Ru-catalyzed method more attractive. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00242DOI Listing

Adaptive Covalent Networks Enabled by Dual Reactivity: The Evolution of Reversible Covalent Bonds, Their Molecular Assemblies, and Guest Recognition.

J Org Chem 2020 Apr 6;85(8):5351-5361. Epub 2020 Apr 6.

State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China.

Adaptive chemistry allows transformation and selection within molecular networks, and adaptive systems composed of different types of dynamic covalent reactions (DCRs) are challenging. Herein, we demonstrate dual reactivity-based covalent networks encompassing the regulation of and switching between C-N- and C-S-based reversible covalent assemblies. The creation and exchange of C-N- or C-S-derived assemblies exhibiting diverse architectures, including linear structures, macrocycles, and cages, were achieved. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00051DOI Listing

Aqueous ZnCl Complex Catalyzed Prins Reaction of Silyl Glyoxylates: Access to Functionalized Tertiary α-Silyl Alcohols.

J Org Chem 2020 May 13;85(9):5825-5837. Epub 2020 Apr 13.

Key Laboratory of Green and Precise Synthetic Chemistry, Ministry of Education; Department of Chemistry, Huaibei Normal University, Huaibei, Anhui 235000, P. R. China.

An efficient Prins reaction of silyl glyoxylates in the presence of an aqueous ZnCl complex as a catalyst was developed, providing functionalized tertiary α-silyl alcohols in high yields under mild conditions. A preliminary investigation indicated that the aqueous ZnCl complex acted as a dual functional catalyst of Brønsted and Lewis acid to activate the carbonyl groups of silyl glyoxylates via a dual-activation model. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03501DOI Listing

Gentianelloids A and B: Immunosuppressive 10,11--Gentianellane Sesterterpenoids from the Traditional Uighur Medicine .

J Org Chem 2020 Apr 1;85(8):5511-5515. Epub 2020 Apr 1.

State Key Laboratory of Phytochemistry and Plant Resources in West China, and Yunnan Key Laboratory of Natural Medicinal Chemistry, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, P. R. China.

Two sesterterpenoids, possessing an unusual 10,11--gentianellane skeleton, gentianelloids A and B, were isolated from a traditional Uighur medicine . Through extensive spectroscopic analysis and single-crystal X-ray diffraction, their structures including absolute configurations were unambiguously determined. A plausible biosynthetic pathway for the two compounds was proposed. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00272DOI Listing

Synthesis of Amide Enol Carbamates and Carbonates through Cu(OTf)-Catalyzed Reactions of Ynamides with -Butyl Carbamates/Carbonates.

J Org Chem 2020 Apr 23;85(7):4740-4752. Epub 2020 Mar 23.

Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.

A highly regioselective approach to access amide enol carbamates and carbonates -, -, and was developed through Cu(OTf)-catalyzed reactions of ynamides with -butyl carbamates and and -butyl carbonates . Moreover, this strategy was successfully applied to generate amide enol carbamates - and - from imides and with ynamides through an -Boc cleavage-addition ring-opening process. A range of substituents was amenable to this transformation, and the desired amide enol carbamates and carbonates were obtained in moderate to good yields. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03512DOI Listing

TfO-Mediated Cyclization of α-Acyl-β-(2-aminopyridinyl)acrylamides: Access to N-Substituted 4-Pyrido[1,2-]pyrimidin-4-imines.

J Org Chem 2020 Apr 17;85(7):4695-4705. Epub 2020 Mar 17.

CAS Key Laboratory of High-Performance Synthetic Rubber and Its Composite Materials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.

A facile and efficient direct synthesis of N-substituted 4-pyrido[1,2-]pyrimidin-4-imines is developed from α-acyl-β-(2-aminopyridinyl)acrylamides mediated by triflic anhydride (TfO) in the presence of 2-chloropyridine. This amide activation protocol features mild reaction conditions, simple execution, excellent yields, and high chemoselectivity, and is also applied to the synthesis of substituted 4-pyrido[1,2-]pyrimidin-4-ones via a practical one-pot procedure. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03495DOI Listing

A General Method for Photocatalytic Decarboxylative Hydroxylation of Carboxylic Acids.

J Org Chem 2020 Apr 17;85(7):5019-5026. Epub 2020 Mar 17.

Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Pharmacy, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, China.

A general and practical method for decarboxylative hydroxylation of carboxylic acids was developed through visible light-induced photocatalysis using molecular oxygen as the green oxidant. The addition of NaBH to in situ reduce the unstable peroxyl radical intermediate much broadened the substrate scope. Different sp carbon-bearing carboxylic acids were successfully employed as substrates, including phenylacetic acid-type substrates, as well as aliphatic carboxylic acids. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00312DOI Listing

Palladium-Catalyzed, Copper(I)-Promoted Methoxycarbonylation of Arylboronic Acids with -Methyl -Aryl Thiocarbonates.

J Org Chem 2020 Mar 3;85(6):4475-4481. Epub 2020 Mar 3.

Chinese Academy of Sciences Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Shanghai 201203, China.

Here, we report -methyl -aryl thiocarbonates as a versatile esterification reagent for palladium-catalyzed methoxycarbonylation of arylboronic acid in the presence of copper(I) thiophene-2-carboxylate (CuTC). The reaction condition is mild, and a variety of substituents including sensitive -Cl, -Br, and free -NH could be tolerated. Further applications in the late-stage esterification of some pharmaceutical drugs demonstrate the broad utility of this method. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00198DOI Listing

Copper(II)-Mediated Intramolecular Cyclopropanation of Ketene ,-Acetals (X = S, O, N) under Mild Conditions.

J Org Chem 2020 Mar 27;85(6):4373-4385. Epub 2020 Feb 27.

Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China.

CuBr-mediated intramolecular oxidative cyclopropanation of α-oxo ketene ,-acetals was efficiently achieved to afford 2-thioalkyl-3-azabicyclo-[3.1.0]hexenes under mild conditions. Read More

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http://dx.doi.org/10.1021/acs.joc.0c00093DOI Listing

Synthesis of Highly Fused Pyrano[2,3-]pyridines via Rh(III)-Catalyzed C-H Activation and Intramolecular Cascade Annulation under Room Temperature.

J Org Chem 2020 May 25;85(10):6281-6294. Epub 2020 Feb 25.

State Key Laboratory of Drug Research and CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China.

A facile access to the polycyclic-fused pyrano[2,3-]pyridines has been established under room temperature via Rh(III)-catalyzed C-H bond activation and intramolecular cascade annulation. This strategy features high efficiency, unique versatility, and generality and it can occur under mild conditions in good to excellent yields. More importantly, this strategy can be extended to the late-stage functionalization of drugs possessing the CN group. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03102DOI Listing

Daphnillonins A and B: Alkaloids Representing Two Unknown Carbon Skeletons from .

J Org Chem 2020 Mar 18;85(5):3742-3747. Epub 2020 Feb 18.

State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, People's Republic of China.

Two highly rearranged daphniphyllum alkaloids, daphnillonins A () and B (), were isolated from and structurally characterized by a combination of diverse methods, including the calculation of electronic circular dichroism. Compound possesses an unprecedented carbon architecture with a very unique 8-methyl-6-azabicyclo[3.2. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03310DOI Listing

Iodine-Catalyzed Three-Component Cascade Reaction for the Synthesis of Substituted 2-Phenylnaphtho[1,3]selenazoles under Transition-Metal-Free Conditions.

J Org Chem 2020 Mar 19;85(5):3349-3357. Epub 2020 Feb 19.

National & Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research, Ministry of Education, Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, Hunan Normal University, Changsha, Hunan 410081, China.

An efficient molecular iodine-catalyzed three-component cascade reaction for the construction of 2-phenylnaphtho[2,1-]selenazoles from naphthalen-2-amine, aldehydes, and selenium powder has been developed. The present approach has the advantages of metal-free conditions, simple operation, and available raw materials. Moreover, the mechanism of the study proved that the reaction underwent a radical process. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03154DOI Listing

FeCl-Promoted Annulation of 2-Haloindoles: Switchable Synthesis of Spirooxindole-chromeno[2,3-]indoles and Spirooxindole-chromeno[3,2-]indoles.

J Org Chem 2020 Mar 21;85(5):3638-3654. Epub 2020 Feb 21.

School of Life Science and Technology (SLST), ShanghaiTech University, 100 Haike Road, Shanghai 201210, China.

Electrophilic indoles bearing a leaving group at C2 undergo C3-regioselective dearomative hydroaryloxylation and subsequent 1,2-tertiary alkyl migration/aromatization. This is the first ring-opening migration of the spiroindolenine intermediate formed by the C3 nucleophilic addition reaction. Various spiro-oxindole-chromeno[3,2-]/[2,3-]indoles were successfully synthesized in excellent yields (up to 98%). Read More

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http://dx.doi.org/10.1021/acs.joc.9b03300DOI Listing

Two Ligands Transfer from Ag to Pd: En Route to (SIPr)Pd(CFH)(X) and Its Application in One-Pot C-H Borylation/Difluoromethylation.

J Org Chem 2020 Mar 4;85(5):3596-3604. Epub 2020 Feb 4.

Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China.

A process for the concurrent transfer of both the NHC ligand and the difluoromethyl group from [(SIPr)Ag(CFH)] to PdX (X = Cl, OAc, and OPiv) for the preparation of [(SIPr)Pd(CFH)X] complexes is described. These complexes were air-stable and easily underwent transmetalation with aryl pinacol boronate/reductive elimination to generate ArCFH in high yields. Based on this discovery, the first one-pot C-H borylation and difluoromethylation process for the preparation of difluoromethylated (hetero)arenes was developed. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03296DOI Listing

Pd(II)-Catalyzed Asymmetric Annulation toward the Synthesis of 2,3-Disubstituted Chiral Indenols.

J Org Chem 2020 Mar 30;85(5):3887-3893. Epub 2020 Jan 30.

State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China.

An enantioselective asymmetric annulation of 2-formylboronic acids with internal alkynes has been realized using a chiral phosphinooxazoline/palladium(II) catalyst. The reaction tolerates a variety of alkynes including the relatively inert diaryl substituted internal ones. A wide range of optically active 2,3-disubstituted indenols was afforded in high yields with good to excellent enantioselectivities (up to 99% yield and 99% ee). Read More

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http://dx.doi.org/10.1021/acs.joc.9b02958DOI Listing

Base Catalyzed Abnormal [3 + 2]-Cycloaddition between Isatin ,'-Cyclic Azomethine Imine 1,3-Dipole and 3-Methyleneoxindole for the One-Step Construction of Tetracyclic Bispirooxindoles.

J Org Chem 2020 Mar 28;85(5):3921-3928. Epub 2020 Jan 28.

Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P.R. China.

An abnormal [3 + 2]-cycloaddition and highly effective and convenient one-step preparation of tetracyclic bispirooxindoles containing two all-carbon quaternary spirocenters from isatin ,'-cyclic azomethine imine 1,3-dipole and 3-methyleneoxindole in the presence of catalytic organic base has been disclosed. A variety of bispirooxindoles bearing a dinitrogen heterocycle with four adjacent cycles have been obtained in excellent yields (up to 95%) and diastereoselectivities (>99:1) under mild conditions. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03050DOI Listing

Regioselective Reversal Cyclization To Access either Eight-Membered Sulfur-Containing Heterocycle-Fused γ-Pyrones or 2-(1,4-Dithianyl)-4-pyrones from the Same Precursors.

J Org Chem 2020 Feb 22;85(4):2575-2584. Epub 2020 Jan 22.

Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) , Hunan Normal University , Changsha 410081 , China.

A regioselective reverse strategy for the construction of eight-membered sulfur-containing heterocycle-fused γ-pyrones and 2-(1,4-dithianyl)-4-pyrones starting from 2-diazo-γ-pyrones and dithioacetals was achieved for the first time. The process combines C-S bond formation via sulfur ylides and C-C bond formation via electron transfer to afford the target molecules in a facile manner with 100% regioselectivity and in excellent isolated yields (up to 90%). Read More

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http://dx.doi.org/10.1021/acs.joc.9b03303DOI Listing
February 2020

Synthesis and Rhodium(II)-Mediated Cascade Cyclopropanation/Rearrangement/Isomerization of Diazo 2,3,5-Trisubstituted Furans: The Construction of Penta-substituted Aromatic Compounds.

J Org Chem 2020 Feb 17;85(4):2395-2405. Epub 2020 Jan 17.

Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) , Hunan Normal University , Changsha 410081 , China.

Ag(I)-catalyzed synthesis of diazo-trisubstituted furans starting from diazo-cumulated allenyl ketones has been investigated. The Rh(OAc)-catalyzed reaction of the diazo 2,3,5-trisubstituted furans provided penta-substituted aromatics via cascade intermolecular cyclopropanation/rearrangement/isomerization. The cyclopropanation on the furan ring/rearrangement of cyclopropane moiety has been reported. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03093DOI Listing
February 2020

Ruthenium(II)-Catalyzed Regioselective Ortho C-H Allenylation of Electron-Rich Aniline and Phenol Derivatives.

J Org Chem 2020 Feb 8;85(4):2048-2058. Epub 2020 Jan 8.

State Key Laboratory of Drug Research , Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu Chong Zhi Road , Shanghai 201203 , China.

Ortho C-H allenylation of electron-rich benzene derivatives with propargylic alcohol derivatives has been a challenge, due to their great innate tendency toward a para C-H allenylation via an SN'-type substitution process. Here, we described a Ru(II)-catalyzed regioselective ortho C-H allenylation of electron-rich aniline and phenol derivatives, which allows the previously challenging synthesis of a broad range of ortho allenylated aniline and phenol derivatives. More significantly, highly optically active fully substituted allenes can also be prepared with high enantiomeric excess via a highly efficient chirality transfer. Read More

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http://dx.doi.org/10.1021/acs.joc.9b02787DOI Listing
February 2020

Rhodium(III)-Catalyzed Decarboxylative Aminomethylation of Glycine Derivatives with Indoles via C-H Activation.

J Org Chem 2020 Feb 10;85(4):2838-2845. Epub 2020 Jan 10.

State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Science, Chinese Academy of Sciences , 354 Fenglin Road , Shanghai 200032 , China.

A rhodium(III)-catalyzed decarboxylative aminomethylation of glycine derivatives with indoles bearing a pyrimidine directing group was developed via C-H activation, exclusively affording the corresponding aminomethylated products with C3 selectivity. In this synthetic protocol, easily available and resourceful arylglycines were utilized as aminomethyl functional moieties. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03365DOI Listing
February 2020

Copper-Catalyzed Electrochemical Selective Bromination of 8-Aminoquinoline Amide Using NHBr as the Brominating Reagent.

J Org Chem 2020 Mar 6;85(5):3497-3507. Epub 2020 Feb 6.

State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.

A simple and mild protocol for copper-catalyzed bromination of quinoline at the C5 site of quinoline by anodic oxidation was developed, affording the desired remote C-H activation products with isolated yields of up to about 90%. The reaction proceeds with low-cost NHBr and shows mild and green conditions (electricity as a green oxidant; NH and H as byproducts). At the same time, a gram-scale bromination reaction was also successfully fulfilled, showing its potential applicable value in organic synthesis. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03223DOI Listing

Chiral and Regenerable NAD(P)H Models Enabled Biomimetic Asymmetric Reduction: Design, Synthesis, Scope, and Mechanistic Studies.

J Org Chem 2020 Feb 10;85(4):2355-2368. Epub 2020 Jan 10.

State Key Laboratory of Catalysis , Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023 , P. R. China.

The coenzyme NAD(P)H plays an important role in electron as well as proton transmission in the cell. Thus, a variety of NAD(P)H models have been involved in biomimetic reduction, such as stoichiometric Hantzsch esters and achiral regenerable dihydrophenantheridine. However, the development of a general and new-generation biomimetic asymmetric reduction is still a long-term challenge. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03054DOI Listing
February 2020

Synthesis of CBD and Its Derivatives Bearing Various C4'-Side Chains with a Late-Stage Diversification Method.

J Org Chem 2020 Feb 8;85(4):2704-2715. Epub 2020 Jan 8.

The Key Laboratory of Plant Resources and Chemistry in Arid Regions and Key Laboratory of Xinjiang Indigenous Medicinal Plants Resource Utilization , Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , South Beijing Road 40-1 , Urumqi , Xinjiang 830011 , People's Republic of China.

A novel synthetic route for making (-)-CBD and its derivatives bearing various C4'-side chains is developed by a late-stage diversification method. Starting from commercially available phloroglucinol, the key intermediate (-)-CBD-2OPiv-OTf is efficiently and regioselectively prepared and further undergoes Negishi cross-coupling to furnish (-)-CBD. This approach allowed an efficient synthesis of (-)-CBD in a five-step total 52% yield on a 10 g scale. Read More

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http://dx.doi.org/10.1021/acs.joc.9b02880DOI Listing
February 2020

One-Pot Synthesis of Spirocyclopenta[]indene Derivatives via a Cascade Ring Expansion and Intramolecular Friedel-Crafts-Type Cyclization.

J Org Chem 2020 Feb 8;85(4):2438-2455. Epub 2020 Jan 8.

Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering , East China University of Science and Technology , 130 Mei Long Road , Shanghai 200237 , People's Republic of China.

A one-pot efficient synthetic approach for the rapid construction of spirocyclopenta[]indene derivatives has been developed via an iodine-initiated cascade ring expansion and intramolecular Friedel-Crafts-type cyclization from propargyl alcohol-tethered alkylidenecyclobutanes under mild conditions with broad substrate scope. This cascade process can be elegantly conducted on a gram scale. A plausible reaction mechanism has been proposed on the basis of a series of deuterium labeling and control experiments. Read More

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http://dx.doi.org/10.1021/acs.joc.9b03126DOI Listing
February 2020

Copper-Catalyzed Annulative Coupling of S,S-Disubstituted Enones with Diazo Compounds to Access Highly Functionalized Thiophene Derivatives.

J Org Chem 2020 Jan 3;85(2):1044-1053. Epub 2020 Jan 3.

Dalian Institute of Chemical Physics , Chinese Academy of Sciences , 457 Zhongshan Road , Dalian 116023 , People's Republic of China.

An efficient protocol toward fully substituted thiophenes and thieno[2,3-]thiophenes has been developed through CuCl-catalyzed annulative coupling of S,S-disubstituted enones with diazo compounds under mild conditions. Tetrasubstituted thiophenes and thieno[2,3-]thiophenes were efficiently accessed by variation of the feed ratio of the reactants in good to excellent yields, respectively. The synthetic methodology has demonstrated the potential for the construction of diverse thiophene derivatives. Read More

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http://dx.doi.org/10.1021/acs.joc.9b02982DOI Listing
January 2020

Visible Light-Promoted Phosphine-Catalyzed Difluoroalkylation of Arenes and Heterocycles.

J Org Chem 2020 Jan 3;85(2):942-951. Epub 2020 Jan 3.

School of Life Science and Technology , ShanghaiTech University , Shanghai 201210 , China.

A visible light-promoted difluoroalkylation reaction of arenes or heterocycles, using triaryl phosphine as the catalyst and difluoroalkyl iodide as the alkylating agent, is presented. The strategy is highlighted by photocatalyst-free, mild reaction conditions and a broad substrate scope. Mechanistic experiments indicate that this reaction involves a radical-chain process that is initiated by an electron donor-acceptor complex formed from difluoroalkyl iodide and phosphine. Read More

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http://dx.doi.org/10.1021/acs.joc.9b02882DOI Listing
January 2020
4.721 Impact Factor

Regioselective Synthesis of Functionalized Dihydropyrones via the Petasis Reaction.

J Org Chem 2020 Jan 26;85(2):1285-1290. Epub 2019 Dec 26.

CAS Key Laboratory of Energy Regulation Materials , Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China.

A novel synthesis methodology for the construction of functionalized dihydropyrones has been developed with amines, glyoxylic acid, and 4-substituted-1,2-oxaborol-2(5)-ols from the Petasis reaction. Mechanistic investigation indicated the intermolecular S2 cyclization to provide 3,6-dihydro-2-pyran-2-ones (3,6-DHP) and 5,6-dihydro-2-pyran-2-ones (5,6-DHP) in one step with moderate to excellent yields. Read More

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http://dx.doi.org/10.1021/acs.joc.9b02651DOI Listing
January 2020

Total Syntheses of (-)-Deoxoapodine, (-)-Kopsifoline D, and (-)-Beninine.

J Org Chem 2020 Jan 26;85(2):967-976. Epub 2019 Dec 26.

Department of Chemistry and State Key Laboratory of Synthetic Chemistry , The Chinese University of Hong Kong , Shatin 100051 , New Territories , Hong Kong SAR, China.

The total syntheses of and alkaloids (-)-deoxoapodine, (-)-kopsifoline D, and (-)-beninine are described through a domino deprotection-Michael addition-nucleophilic substitution protocol to assemble the core framework in efficient steps. Corey-Bakshi-Shibata reduction was employed to afford the enantioenriched intermediate for the total syntheses of the aforementioned alkaloids. The chirality was shown to completely transfer to the backbone using Johnson-Claisen rearrangement. Read More

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http://dx.doi.org/10.1021/acs.joc.9b02918DOI Listing
January 2020
4.721 Impact Factor

One-Pot Methylenation-Cyclization Employing Two Molecules of CO with Arylamines and Enaminones.

J Org Chem 2020 Jan 18;85(2):912-923. Epub 2019 Dec 18.

School of Chemistry and Chemical Engineering , Qufu Normal University , Qufu 273165 , China.

One-pot methylenation-cyclization employing two molecules of CO with enaminones and primary aromatic amines was discussed for the first time to access cyclized products. This 1,5,7-triazabicyclo[4.4. Read More

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http://dx.doi.org/10.1021/acs.joc.9b02858DOI Listing
January 2020