Publications by authors named "Ian Crossley"

22 Publications

  • Page 1 of 1

A Benzodiphosphaborolediide.

Chemistry 2021 Nov 8;27(66):16342-16346. Epub 2021 Oct 8.

Department of Chemistry, University of Sussex, Falmer, Brighton, BN1 9QJ, UK.

The first example of a diphosphaborolediide, the benzo-fused [C H P BPh] (1 ), is prepared from ortho-bis(phosphino)benzene (C H {PH }) and dichlorophenylborane, via a sequential lithiation approach. The dilithio-salt can be obtained as an oligomeric THF solvate or discrete TMEDA adduct, both of which are fully characterized, including by X-ray diffraction. Alongside NICS calculations, data strongly suggest some aromaticity within 1 , which is further supported by preliminary coordination studies that demonstrate η -coordination to a zerovalent molybdenum center, as observed crystallographically for the oligomeric [{Mo(CO) (η -1)}{μ-η -Mo(CO) (TMEDA)} ] ⋅ [μ-Li(THF)][μ-Li(TMEDA)].
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http://dx.doi.org/10.1002/chem.202103427DOI Listing
November 2021

Diphosphametacyclophanes: Structural and Electronic Influences of Substituent Variation within a Family of Bis(diketophosphanyl) Macrocycles.

J Org Chem 2020 Nov 19;85(22):14697-14707. Epub 2020 Oct 19.

Department of Chemistry, University of Sussex, Falmer, Brighton BN1 9QJ, United Kingdom.

The condensation of MeP(SiMe) with a series of 5-substituted isophthaloyl chlorides (5-R'CH-2,6-{C(O)Cl}) affords the diphosphametacyclophanes -{-C(O)-CH-5-R'-(C(O)PMe)} (R' = I, Me, Bu, Ph, and -NCCH); the analogues -{-C(O)-CHN-(C(O)PMe)} and -{-C(O)-CH-(C(O)PPh)} are similarly obtained in preference to higher oligomers, in contrast to precedent reports. The cyclophanes all adopt butterfly-like conformations in the solid state with the P-organyl substituents adopting mutually arrangements. Structural and computational data suggest the nature of the 5-R substituent is key in directing the inter-ring angle and the extent of LUMO stabilization about the diketophophanyl scaffold. The latter is substantiated by UV/vis spectroscopy and cyclic voltammetry, which demonstrate these cyclophanes to be appreciably comparable to the diketophosphanyl systems commonly explored in the context of organic electronic materials; intriguingly, the distinct dikeophosphanyl moieties within the macrocycles appear effectively "insulated" by the macrocycle geometry, rather than acting as a through-conjugate.
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http://dx.doi.org/10.1021/acs.joc.0c01950DOI Listing
November 2020

Phosphacycloalkyldiones: synthesis and coordinative behaviour of 6- and 7-member cyclic diketophosphanyls.

Dalton Trans 2020 May 7;49(17):5482-5492. Epub 2020 Apr 7.

Department of Chemistry, University of Sussex, Brighton, UK.

Glutaryl and adipoyl chlorides undergo facile condensation with the bis(silyl)phosphanes RP(SiMe) (R = Me, Bu, Bu, Ph, Mes) to afford exclusively the phosphacycloalkyldiones (CH)(C[double bond, length as m-dash]O)PR (n = 3, 4). Characterised spectroscopically and, for R = Ph, Mes (n = 3) crystallographically, the macrocycles are conformationally fluxional in solution and appreciably moisture sensitive. Though seemingly resistant to chemical oxidation at phosphorus, coordination is readily achieved, as illustrated by isolation of trans-[Pt(PEt){P(Ph)(CO)(CH)}Cl] and a series of tungsten pentacarbonyl complexes, which are characterised crystallographically and by infrared and NMR spectroscopy. Together, these data suggest the macrocycles to be relatively weak σ-donors with no appreciable π-acceptor character.
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http://dx.doi.org/10.1039/d0dt00864hDOI Listing
May 2020

Controlled Reactivity of Terminal Cyaphide Complexes: Isolation of the 5-Coordinate [Ru(dppe)(C≡P)].

Inorg Chem 2019 Nov 21;58(21):14800-14807. Epub 2019 Oct 21.

Department of Chemistry , University of Sussex , Falmer , Brighton BN1 9QJ , U.K.

The novel cyaphide complex -[Ru(dppe)Me(C≡P)] is obtained in excellent yields and exhibits the first instance of controlled reactivity of any terminal cyaphide complex. Its treatment with ZnX/PPh effects selective metathesis of the methyl moiety to afford the unprecedented halocyaphide complexes -[Ru(dppe)(X)(C≡P)] (X = Cl, Br, I), which are structurally characterized (X = Cl, Br). Exemplified with the -bromide, these compounds are susceptible to substitution of the halides by nucleophilic reagents-illustrated with MeMg-and also readily undergo halide abstraction by TlOTf to afford the first hypocoordinate cyaphide complex, viz., [Ru(dppe)(C≡P)]·OTf, which is isolable in bulk and exhibits good stability. NMR spectroscopic and crystallographic data reveal the latter to adopt a square-pyramidal geometry with an accessible coordinate vacancy, which is susceptible to the addition of nucleophiles. This is illustrated analytically by reactions with MeMg and LiC≡CPh and with its facile bulk carbonylation to afford -[Ru(dppe)(CO)(C≡P)].
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http://dx.doi.org/10.1021/acs.inorgchem.9b02471DOI Listing
November 2019

Correction: Cyaphide-alkynyl complexes: metal-ligand conjugation and the influence of remote substituents.

Dalton Trans 2019 Sep 15;48(34):13101. Epub 2019 Aug 15.

Department of Chemistry, University of Sussex, Brighton, UK.

Correction for 'Cyaphide-alkynyl complexes: metal-ligand conjugation and the influence of remote substituents' by Samantha K. Furfari, et al., Dalton Trans., 2019, 48, 8131-8143.
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http://dx.doi.org/10.1039/c9dt90184aDOI Listing
September 2019

Cyaphide-alkynyl complexes: metal-ligand conjugation and the influence of remote substituents.

Dalton Trans 2019 Jun 7;48(23):8131-8143. Epub 2019 May 7.

Department of Chemistry, University of Sussex, Brighton, UK.

A homologous series of novel trans-cyaphide-alkynyl complexes, viz. trans-[Ru(dppe)(C[triple bond, length as m-dash]P)(C[triple bond, length as m-dash]CCHR-p)] (R = Me, H, F, COMe, NO) is prepared and comprehensively characterised, alongside their parent phosphaalkyne-complex cations trans-[Ru(dppe)(η-P[triple bond, length as m-dash]CSiMe)(C[triple bond, length as m-dash]CCHR-p)]. Structural data for trans-[Ru(dppe)(C[triple bond, length as m-dash]P)(C[triple bond, length as m-dash]CCHR-p)] (R = Me, F) and trans-[Ru(dppe)(η-P[triple bond, length as m-dash]CSiMe)(C[triple bond, length as m-dash]CCHR-p)] (R = F, COMe) are described, along with that for the previously reported trans-[Ru(dppe)(C[triple bond, length as m-dash]P)(C[triple bond, length as m-dash]CCOMe)]. NMR spectroscopic data indicate significant influence of the remote aromatic substituent over the properties of the cyaphide ligand, in line with the Hammett parameter (σ), suggesting appreciable 'communication' along the through-conjugate chain. Cyclic voltammety shows irreversible oxidative behaviour, at more anodic E than in the respective alkynyl-chloride complexes, though apparently moderated by the remote substituent.
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http://dx.doi.org/10.1039/c9dt01071hDOI Listing
June 2019

Through-conjugation of two phosphaalkyne ('C[triple bond, length as m-dash]P') moieties mediated by a bimetallic scaffold.

Dalton Trans 2018 Mar;47(13):4428-4432

Department of Chemistry, University of Sussex, Brighton, UK.

Through-conjugation of two phosphaalkyne moieties within an isolable molecule is demonstrated for the first time with the synthesis of [{Ru(dppe)2}2{μ-(C[triple bond, length as m-dash]C)2C6H4-p}(C[triple bond, length as m-dash]P)2], via base-induced desilylation of [{Ru(dppe)2}2{μ-(C[triple bond, length as m-dash]C)2C6H4-p}(η1-P[triple bond, length as m-dash]CSiMe3)2]2+. The nature of the cyaphide ligands and their influence upon the bimetallic core are studied electrochemically.
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http://dx.doi.org/10.1039/c8dt00110cDOI Listing
March 2018

Synthesis of 3-stannyl and 3-silyl propargyl phosphanes and the formation of a phosphinoallene.

Dalton Trans 2016 Feb 9;45(5):2148-55. Epub 2015 Nov 9.

Department of Chemistry, University of Sussex, Brighton, UK.

The group 14 chloropropargyls R3EC ≡ CCH2Cl (R3E = (n)Bu3Sn, Ph3Sn, Me2PhSi, (i)Pr3Si, (n)Pr3Si, (n)Bu3Si), obtained by a modified literature procedure, react with LiPPh2 to afford the novel propargyl phosphanes Ph2PCH2C ≡ CER3 in high yield, as viscous oils; (Me3Si)2PCH2C ≡ CSiPhMe2 is similarly obtained from LiP(SiMe3)2. In contrast, the reaction of PhC[triple bond, length as m-dash]CCH2MgCl with ClP(NEt2)2 fails to produce a comparable propargyl phosphane, but generates preferentially (>70%) the novel phosphinoallene (Et2N)2PC(Ph) = C = CH2, which is characterised spectroscopically, and through its reaction with HCl. The coordination chemistry of representative phosphanes is explored with respect to platinum and palladium for the first time.
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http://dx.doi.org/10.1039/c5dt03558aDOI Listing
February 2016

A young pregnant woman with spontaneous carotid artery dissection--unknown mechanisms.

BMJ Case Rep 2014 May 30;2014. Epub 2014 May 30.

Stafford Hospital, Stafford, UK.

Spontaneous carotid artery dissection in pregnancy has not been reported before. We present a case of a 31-year-old Caucasian woman who was 11 weeks pregnant and presented with neck pain, headache, vomiting and left side Horner's syndrome. Subsequent investigations with MR angiography confirmed spontaneous left internal carotid artery dissection.
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http://dx.doi.org/10.1136/bcr-2013-202541DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4039886PMC
May 2014

Synthesis and electronic structure of the first cyaphide-alkynyl complexes.

Dalton Trans 2014 Jun;43(24):9004-7

Department of Chemistry, University of Sussex, Brighton, UK.

The novel complexes trans-[Ru(dppe)2(C≡CR)(C≡P)] (R = CO2Me, C6H4OMe), the first to incorporate cyaphide as part of a conjugated system, are obtained in facile manner. The electronic structure of these compounds is probed by X-ray, DFT and UV/Vis studies.
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http://dx.doi.org/10.1039/c4dt01108bDOI Listing
June 2014

Retained temporary epicardial pacing wires: a rare cause of prosthetic valve endocarditis.

J Coll Physicians Surg Pak 2013 Sep;23(9):657-9

Department of Cardiology, University Hospital of North Staffordshire, UK.

Temporary epicardial pacing wires (TEPWs) are commonly used during cardiac surgery to meet unforeseen complications like heart blocks or asystole. These are generally considered to be safe. The incidence of major complications with their use is low, but could be life threatening. Complications can be divided into those encountered during placement, removal, or retention of temporary epicardial pacing wires. We report a rare case of prosthetic mitral valve endocarditis caused by TEPWs that migrated into the pulmonary artery, presenting 5 months following mitral and aortic valve replacement surgery that required percutaneous removal of these temporary pacing wires via a right femoral vein approach. This case highlights the fact that delayed complications can rarely occur due to retained TEPWs and may have serious consequences. This fact should be taken into account when the strategy on dealing with such wires following cardiac surgery is determined. Routine retention of temporary epicardial pacing wires is not recommended.
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http://dx.doi.org/09.2013/JCPSP.657659DOI Listing
September 2013

Facile self-assembly of the first diphosphametacyclophane.

Chem Commun (Camb) 2012 Jun 2;48(46):5766-8. Epub 2012 May 2.

Department of Chemistry, University of Sussex, Brighton, UK.

The reaction of isophthaloyl chloride and methyl-bis(trimethylsilyl)phosphane under mild conditions affords high yields of m-{-C(O)-C(6)H(4)(C(O)PMe)}(2) (1,10-dimethyl-1,10-diphospha-[3.3]-metacyclophane-2,9,11,18-tetraone): the first example of a diphosphametacyclophane.
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http://dx.doi.org/10.1039/c2cc32247aDOI Listing
June 2012

The open-chain triphosphanes RMe2SiCH2P(PR'2)2 (R = Me, Ph; R' = SiMe3, Cy, Ph).

Dalton Trans 2012 Jan 9;41(1):278-84. Epub 2011 Nov 9.

Department of Chemistry, University of Sussex, Falmer, Brighton, UK.

The triphosphanes RMe(2)SiCH(2)P(PR'(2))(2) (R = Me, Ph; R' = SiMe(3), Cy) are synthesised in good yield via metathesis of organodichlorophosphanes and LiPR'(2), while for R' = Ph a propensity to form (Ph(2)P)(2) precludes isolation of the in situ characterised triphosphanes. Where R = Me and R' = SiMe(3) the triphosphane has also been characterised by single crystal X-ray diffraction and exhibits a single geometric conformer in the solid state, though solution-phase NMR spectra are indicative of facile conformational exchange across a wide temperature range. All of the described triphosphanes exhibit comparable behaviour, with their respective (31)P{(1)H} NMR spectra manifesting anomalous 'second-order' characteristics, which are considered using full spin-Hamiltonian simulation. Preliminary studies of coordination chemistry and ancillary reactivity of the triphosphanes are described.
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http://dx.doi.org/10.1039/c1dt11499aDOI Listing
January 2012

Synthesis of gold(I) fluoroalkyl and fluoroalkenyl-substituted phosphine complexes and factors affecting their crystal packing.

Dalton Trans 2011 Feb 6;40(8):1743-50. Epub 2010 Dec 6.

School of Chemistry, University of Manchester, Manchester.

A series of gold(I) phosphine complexes of the type [AuCl{PR(2)(R(f))}] (R = Et, i-Pr, Cy; R(f) = CF = CF(2); R = Ph, R(f) = C = CFH, CCl = CF(2), C ≡ CCF(3), CF(3), i-C(3)F(7), s-C(4)F(9)) have been prepared and most have been structurally characterised. All of the complexes are monomeric in the solid state, and a number of secondary interactions are observed--including short intramolecular AuF distances, metal-bound Au-ClH non-classical hydrogen bonds, fluorous domains and phenyl embraces. Only in the case of [AuCl{PEt(2)(CF = CF(2))}] is an aurophilic interaction with an AuAu contact less than the sum of the van der Waals radii observed. Even then, the distance, 3.3458(10) Å, is longer than that previously observed for the related complex with R = Ph; R(f) = CF = CF(2).
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http://dx.doi.org/10.1039/c0dt01014fDOI Listing
February 2011

Methimazole-based ionic liquids.

J Org Chem 2008 Jun 11;73(12):4676-9. Epub 2008 Apr 11.

School of Chemistry, Monash University, Clayton, VIC, Australia.

The alkylation reaction of 2-mercapto-1-methylimidazole 1a with iodoethane and chlorobutane produced S-alkylmethimazole halides 2a and 2b which were subjected to anion metathesis with two different metal salts (MA) to afford methimazole-based room-temperature ionic liquids 3a, 3b, and 3c in 82%, 85%, and 87% yields, respectively. S-Alkylation giving 2a and 2b suggests that methimazole reacts through the thione tautomer.
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http://dx.doi.org/10.1021/jo702511vDOI Listing
June 2008

Unlocking the metallaboratrane cage: reversible B-H activation in platinaboratranes.

Dalton Trans 2008 Jan 1(2):201-3. Epub 2007 Nov 1.

Research School of Chemistry, Institute of Advanced Studies, Australian National University, Canberra, Australian Capital Territory, Australia.

The reaction of the new platinaboratrane salt [PtH(PTol3){B(mt)3}]Cl(Pt-->B)8 (mt = methimazolyl, Tol = C6H4Me-4) with 2 equivalents of PR3 (R = Me, Et) affords, via hydride migration to boron and ligand substitution, the salts [Pt(PR3)2{kappa 2-S,S'-HB(mt)3}]Cl, which slowly undergo B-H reactivation, to afford, ultimately, the platinaboratrane salts [PtH(PR3){B(mt)3}]Cl(Pt-->B)8.
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http://dx.doi.org/10.1039/b712058cDOI Listing
January 2008

The first rhodaboratrane: [RhCl(PPh3){B(mt)3}](Rh-->B)(mt = methimazolyl).

Chem Commun (Camb) 2005 Jan 25(2):221-3. Epub 2004 Nov 25.

Research School of Chemistry, Institute of Advanced Studies, Australian National University, Canberra, ACT Australia.

The reaction of [Rh(C6H5)Cl2(PPh3)2] with Na[HB(mt)3](mt = methimazolyl) provides [RhCl(PPh3){B(mt)3}](Rh-->B) the first authentic example of a compound with a rhodium-boron dative bond.
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http://dx.doi.org/10.1039/b413305fDOI Listing
January 2005

Caveats for poly(methimazolyl)borate chemistry: the novel inorganic heterocycles [H2C(mt)2BR2]Cl (mt = methimazolyl; BR2 = BH2, BH(mt), 9-BBN).

Chem Commun (Camb) 2004 Aug 7(16):1878-9. Epub 2004 Jul 7.

Research School of Chemistry, Institute of Advanced Studies, Australian National University, Canberra ACT, Australia.

Whilst frequently used for reactions of poly(methimazolyl)borates, dichloromethane is not an innocent solvent, but rather slowly forms heterocyclic salts [H(2)C(mt)(2)BR(2)]Cl, three examples of which (BR(2) = BH(2), BH(mt), 9-borabicyclononyl) have been structurally characterised to confirm the unprecedented B(NCS)(2)C connectivity.
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http://dx.doi.org/10.1039/b407733dDOI Listing
August 2004

Tricarbonyl(eta6-chlorobenzene)chromium.

Acta Crystallogr C 2003 Aug 22;59(Pt 8):m322-4. Epub 2003 Jul 22.

Chemistry Department, UMIST, PO Box 88, Manchester M60 1QD, England.

The title compound, [Cr(C(6)H(5)Cl)(CO)(3)], is the first group 6 tricarbonyl eta(6)-monohaloarene compound to be structurally characterized. It adopts a classic piano-stool structure, with the Cr(CO)(3) tripod assuming a syn-eclipsed conformation relative to the arene ring (varphi = 2.0 degrees ). The extended structure is dominated by intermolecular pi.H interactions (H.ring centroid = 2.94 A) and non-classical hydrogen bonds between carbonyl and arene moieties (O.H = 2.50-2.58 A).
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http://dx.doi.org/10.1107/s0108270103013787DOI Listing
August 2003

Ringing the changes: a remarkable carbene-free synthesis of difluorocyclopropenes.

Angew Chem Int Ed Engl 2003 May;42(21):2399-401

Department of Chemistry, UMIST, P.O. Box 88, Manchester, M60 1QD, UK.

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http://dx.doi.org/10.1002/anie.200250756DOI Listing
May 2003

Hydrofluorocarbon 245fa: a versatile new synthon in alkyne chemistry.

Chem Commun (Camb) 2002 Oct(20):2420-1

Department of Chemistry, UMIST, P.O. Box 88, Manchester M60 1QD, UK.

The CFC replacement 1,1,1,3,3-pentafluoropropane (HFC 245 fa) has been established as a convenient source of trifluoropropynyllithium under mild conditions; a range of novel and known trifluoropropynyl-containing systems has been prepared in a one-pot procedure.
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http://dx.doi.org/10.1039/b207979hDOI Listing
October 2002

Spectroscopic and structural assignment of the absolute stereochemistry in a series of 1,2-difluorovinyl organometalloids. The first crystallographic characterization and structural series of group 14 fluorovinyl compounds.

Inorg Chem 2002 Sep;41(18):4748-55

Department of Chemistry, UMIST, P.O. Box 88, Manchester M60 1QD, U.K.

The group 14 trifluorovinyl compounds Ph(3)ECF=CF(2) (E = Ge, Sn, Pb) have been prepared in high yield by the low-temperature reaction of the triphenylelement halide with trifluorovinyllithium, generated from tetrafluoroethane (CF(3)CH(2)F, HFC-134a) and 2 equiv of n-butyllithium. The X-ray crystal structures of these materials have been obtained, so affording the first structural series for such species. Subsequent reaction of Ph(3)GeCF=CF(2) with LiAlH(4) and a range of organolithium reagents has led to preparation of the 1,2-difluorovinylgermanes Ph(3)GeCF=CFR (R = H, Me, n-Bu, t-Bu, Ph). Multinuclear NMR spectroscopic and X-ray crystallographic studies of these compounds have been undertaken and have shown unequivocally the exclusive trans-geometry of the 1,2-difluorovinyl moiety.
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http://dx.doi.org/10.1021/ic025593oDOI Listing
September 2002
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