8 results match your criteria carboranes generally

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Nucleophilic substitution: a facile strategy for selective B-H functionalization of carboranes.

Dalton Trans 2019 Jun 26;48(22):7494-7498. Epub 2019 Apr 26.

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

Vertex-specific functionalization of carboranes has received considerable research interest, due to the valuable application of carborane derivatives in medicine, coordination/organometallic chemistry and materials. In comparison with a protic cage C-H bond, cage B-H is hydridic and generally less polar, with a bond dissociation energy of ca. 108 kcal mol. Read More

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Carborane-based polymers: a novel class of semiconductors with tunable properties.

Phys Chem Chem Phys 2017 May;19(18):10986-10997

Department of Chemistry, University of North Texas, 1155 Union Circle #305070, Denton, TX 76203, USA.

Semiconducting boron carbides based on cross-linked carborane (BCH) icosahedra, developed several decades ago, are of significant interest in a variety of emerging areas, including photocatalysis, spintronics, and especially neutron detection. These materials, however, display generally poor charge carrier mobility, high defect levels and other properties that pose significant drawbacks. A class of nanocomposite carborane-based materials has recently been developed, that addresses many of these issues. Read More

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Boron-Based Drug Design.

Chem Rec 2015 Jun 20;15(3):616-35. Epub 2015 Mar 20.

Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan.

The use of the element boron, which is not generally observed in a living body, possesses a high potential for the discovery of new biological activity in pharmaceutical drug design. In this account, we describe our recent developments in boron-based drug design, including boronic acid containing protein tyrosine kinase inhibitors, proteasome inhibitors, and tubulin polymerization inhibitors, and ortho-carborane-containing proteasome activators, hypoxia-inducible factor 1 inhibitors, and topoisomerase inhibitors. Furthermore, we applied a closo-dodecaborate as a water-soluble moiety as well as a boron-10 source for the design of boron carriers in boron neutron capture therapy, such as boronated porphyrins and boron lipids for a liposomal boron delivery system. Read More

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High yielding synthesis of carboranes under mild reaction conditions using a homogeneous silver(I) catalyst: direct evidence of a bimetallic intermediate.

Angew Chem Int Ed Engl 2014 May 2;53(20):5156-60. Epub 2014 Apr 2.

Department of Chemistry and Chemical Biology, McMaster University, 1280 Main St W., Hamilton, Ont., L8S 4M1 Canada; Department of Chemistry, Faculty of Science, Tanta University, 31527 Tanta (Egypt).

Methods used to prepare functionalized carboranes generally require heating to high temperatures, and thus limits the range of derivatives which can be prepared directly from alkynes. We show here that by using a homogeneous silver(I) catalyst it is now possible to prepare carboranes in good to excellent yield at temperatures below 40 °C, including at room temperature. The process is general and provides an important new synthetic strategy for the preparation of functionalized boron clusters. Read More

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Transition metal-carboryne complexes: synthesis, bonding, and reactivity.

Acc Chem Res 2011 Apr 11;44(4):299-309. Epub 2011 Mar 11.

Department of Chemistry, The Chinese University of Hong Kong, Shatin, N. T., People's Republic of China.

The construction and transformation of metal-carbon (M-C) bonds constitute the central themes of organometallic chemistry. Most of the work in this field has focused on traditional M-C bonds involving tetravalent carbon: relatively little attention has been paid to the chemistry of nontraditional metal-carbon (M-C(cage)) bonds, such as carborane cages, in which the carbon is hypervalent. We therefore initiated a research program to study the chemistry of these nontraditional M-C(cage) bonds, with a view toward developing synthetic methodologies for functional carborane derivatives. Read More

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A novel carborane analog, BE360, with a carbon-containing polyhedral boron-cluster is a new selective estrogen receptor modulator for bone.

Biochem Biophys Res Commun 2009 Mar 19;380(2):218-22. Epub 2009 Jan 19.

Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16 Nakamachi, Koganei, Tokyo 184-8588, Japan.

Carboranes are a class of carbon-containing polyhedral boron-cluster compounds with globular geometry and hydrophobic surface that interact with hormone receptors. Estrogen deficiency results in marked bone loss due to increased osteoclastic bone resorption in females, but estrogen replacement therapy is not generally used for postmenopausal osteoporosis due to the risk of uterine cancer. We synthesized a novel carborane compound BE360 to clarify its anti-osteoporosis activity. Read More

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Strikingly long C...C distances in 1,2-disubstituted ortho-carboranes and their dianions.

J Am Chem Soc 2005 Oct;127(39):13538-47

School of Chemistry, University of Bristol, Cantock's Close, Bristol, UK.

Neutral and especially dianionic 6- and 12-vertex closo ortho-carboranes (o-carboranes) 1,2-R2-1,2-C2BnHn (R = H, CH3, NH2, OH, F, SiH3, PH2, SH, Cl, as well as e-, CH2-, NH-, O-, SiH2-, PH-, and S- exhibit extremely large variations (over 1 A!) of the cage CC distances, from 1.626 to 2.638 A, at the B3LYP/6-31G//B3LYP/6-31G DFT level. Read More

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October 2005

Carborane-containing liquid crystals: synthesis and structural, conformational, thermal, and spectroscopic characterization of diheptyl and diheptynyl derivatives of p-carboranes.

Inorg Chem 2001 Dec;40(26):6622-31

Organic Materials Research Group, Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, USA.

Molecular and electronic structures for four p-carborane derivatives were studied in the context of their liquid crystalline properties. Thus molecular and crystal structures of diheptyl and diheptynyl derivatives of 10- and 12-vertex bi-p-carboranes were determined by X-ray crystallography and compared to the results of ab initio calculations at the HF/6-31G level of theory. Experimentally observed significant positional disorder of one of the substituents in the 10-vertex derivatives, 2[2]a and 2[2]b, was related to conformational properties of the alkyl-carborane bond. Read More

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December 2001
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