Showing papers by "John F. Nixon published in 1999"
TL;DR: In this article, a single-crystal X-ray diffraction experiment reveals a discrete molecular structure involving half-sandwich coordination of the P3C2But2 ring around the indium center.
38 citations
TL;DR: In this paper, the molecular geometries of the 1,2,4-selenadiphosphole and 1, 2, 4-telluradiphophosphole aromatic ring systems, established by single crystal X-ray diffraction studies on their metal pentacarbonyl complexes, are presented and discussed together with theoretical data.
27 citations
TL;DR: In this paper, PbCl2 reacts with the triphospholyl ring anion [P3C2But2] to afford the hexaphospha-plumbocene [Pb(η5-P3c2c2bC2bBut2)2] and the organo-antimony cage compound [P4Sb2C4But4] via an oxidative coupling route.
Abstract: PbCl2 reacted with the triphospholyl ring anion [P3C2But2]– to afford the hexaphospha-plumbocene [Pb(η5-P3C2But2)2] 3 which has been characterised by multinuclear NMR spectroscopy. In contrast the reaction between PbCl2 and the diphosphastibolyl ring anion [P2SbC2But2]– led to the organo-antimony cage compound [P4Sb2C4But4] 4via an oxidative coupling route. Both the heteroleptic plumbocenes [Pb(η5-EP2C2But2)(η5-C5Me5)] (E = P 5, E = Sb 6) could be prepared by treatment of the corresponding hetero-ring anion with a mixture of PbCl2 and Li(C5Me5) (for 5) or the half sandwich complex [Pb(η5-C5Me5)Cl] (for 6). Both complexes were characterised by multinuclear NMR spectroscopy and single crystal X-ray diffraction studies. The novel, structurally characterised, hetero-bimetallic complex [Pb(η5-P3C2But2)(µ-Cl)2Li(tmen)2] 7 could be synthesised by carrying out the reaction of PbCl2 with [Li(dme)3][P3C2But2] in tmen rather than dme. This compound was found to be highly fluxional in solution even at low temperature.
27 citations
TL;DR: The Titanocene [Ti(η5-(P3C2But2)2] made by cocondensation of titanium vapour with the phosphaalkyne ButCP and reaction of ButCP with [Ti 6-C6H5Me] at −78 °C or (iii) by heating TiCln with n(KP 3C 2But2 But2) (n = 2, 3) in toluene at 110 °C, undergoes an unusual [2+2] cycloaddition reaction with ButCP to give
23 citations
TL;DR: In this article, the structures of novel complexes resulting from one-and two-step cycloaddition reactions of four group 4 imides with the phosphaalkyne Bu(t)CP are described.
21 citations
TL;DR: In this article, two synthetic routes to the new aromatic 1,2,4-aza-diphosphole ring system P2C2Bu(t)2NR (R = Pr(i), Pr, Ph, MeC6H4, Bu(t), CH2 and cyclohexyl) were presented and the planar structure of P2c2bu(t)-2NPh, established by a single crystal X-ray diffraction study, is in good agreement with theoretical calculations at the B3LYP/6-311G*
21 citations
TL;DR: In this article, single-crystal X-ray diffraction studies on the triphosphaferrocene complex reveal an unusual η 2 -ring edge coordination mode in the latter resulting in a significant elongation of the trphosphacyclopentadienyl ring P-P bond.
17 citations
TL;DR: The stable bis(amino)silylene Si[(NCH2But)2C6H4-1,2] 1 undergoes [1 + 4]-cycloaddition with 2,4,6-tri-tert-butyl 1,3,5-triphosphabenzene 2 to afford compound 3: the molecular structure of 3 is supported by NMR spectroscopic data and confirmed by a single crystal X-ray diffraction study as discussed by the authors.
15 citations
TL;DR: The first examples of η1-complexes of 2,4,6-tri-tert-butyl-1,3,5-triphosphabenzene are described in this article.
14 citations
TL;DR: In this paper, a planar triphospholem was found to be planar according to ab initio geometry optimisation at the HF/3-21G(*) level.
12 citations
TL;DR: In this paper, the first mixed phosphirene-dinitrogen and phosphiresirene−diazenide complexes were prepared by treatment of the corresponding thf solutions of trans-[ReCl(N2)L4] or [ReBr3(NNPh)(PPh3)2] with PPhCPhCphCPhPh.
Abstract: The first mixed phosphirene–dinitrogen and phosphirene–diazenide complexes mer-[ReCl(N2)(PPhCPhCPh)L3] (L = PMe2Ph 1a or PMePh2 1b) and [ReBr(NNPh)2(PPhCPhCPh)2(PPh3)] 2 have been prepared by treatment of the corresponding thf solutions of trans-[ReCl(N2)L4] or [ReBr3(NNPh)(PPh3)2] with PPhCPhCPh. Their redox properties have been investigated by cyclic voltammetry in an aprotic medium, at a platinum electrode, and the electrochemical EL and PL parameters estimated for the phosphirene ligand indicating that its overall electron donor/acceptor properties are similar to those of PMePh2.
TL;DR: In the presence of TlBF4, the authors gave the η4-1,3-diphosphacyclobutadiene complex [Rh(triphos){η4-(PCBut)2}][BF4] 1a which formed the diadducts.
Abstract: Treatment of [RhCl(triphos)] [triphos = PPh(CH2CH2PPh2)2] in thf with PCBut, in the presence of TlBF4, gave the η4-1,3-diphosphacyclobutadiene complex [Rh(triphos){η4-(PCBut)2}][BF4] 1a which formed the diadducts [Rh(triphos){η4∶η1∶η1-[W(CO)5]2(PCBut)2}][BF4] 2 or [Rh(triphos){η4∶η1∶η1-[PtCl2(PEt3)]2(PCBut)2}][BF4] 3 on reaction with [W(CO)5(thf)] or [Pt2Cl4(PEt3)2], respectively. These adducts dissociated in solution, the former in the presence of Na[BPh4] to give [Rh(triphos){η4-(PCBut)2}][BPh4] 1b, and the latter to the mono-η1-adduct [Rh(triphos){η4∶η1-[PtCl2(PEt3)](PCBut)2}][BF4] 4. Reactions of [RhCl(triphos)] in thf with the 1-alkynes HCCR (R = CO2Me or CO2Et) in the presence of Tl[BF4] afforded the corresponding benzene derivative complexes [Rh(triphos){η4-(HCCR)3}][BF4] 5a or 5b.
TL;DR: In this paper, 1,5-Cyclo-octadiene is readily displaced from [Ru(η4-COD] to give the dicarbonyl complex [Ru (CO)2{η5-P3C2But2CH(SiMe3)2}.