Showing papers by "Frederick G. Mann published in 1969"
TL;DR: The 1 : 1 complexes of the chelating diphosphine, 2,2′-biphenylylenebischiethylphosphine with nickel(II) halides and thiocyanate and with palladium(II), bromide have been prepared, and their magnetic properties and electronic and n.m. spectra studied as mentioned in this paper.
Abstract: The 1 : 1 complexes of the chelating diphosphine, 2,2′-biphenylylenebisdiethylphosphine, with nickel(II) halides and thiocyanate and with palladium(II) bromide have been prepared, and their magnetic properties and electronic and n.m.r. spectra studied.The nickel(II) chloride and bromide complexes in solution exhibit square planar-tetrahedral isomerism, while the corresponding iodide and thiocyanate complexes remain exclusively tetrahedral and square-planar respectively. The palladium(II) bromide complex has the square-planar configuration.A brief study has been made of the chelating properties of the analogous diarsine. This gives a stable 1 : 1 complex with palladium(II) bromide but does not apparently give 1 : 1 nickel(II) halide complexes.
12 citations
TL;DR: In this article, the magnetic and spectroscopic properties of 9-alkyl-9-phosphafluorenes are discussed and related to those of other five-coordinate complexes of the above metals.
Abstract: The 9-alkyl-9-phosphafluorenes (I), alternatively named 5-alkyl-5H-dibenzophospholes (Ia; R = Me, Et), form a series of five-co-ordinate complexes of the type phos3 MX2(M = NiII, X = Cl, Br, I, NCS, CN; M = PdII, X = Br; M = Pt,II X = Br, SCN; M = CoII, X = Br), which are stable in the solid state but which undergo reversible dissociation in solution in certain organic solvents The magnetic and spectroscopic properties of the complexes are discussed and related to those of other five-co-ordinate complexes of the above metals The nickel(II) complexes are unusual in having magnetic moments in the range from 0·65–1·5 BM, whereas the corresponding cobalt(II) complexes are of the normal low-spin type, having moments of 1·95 BMEvidence for the structure of dicyanotris(9-methyl-9-phosphafluorene)nickel(II) has been adduced by X-ray crystallographic analysisFour-co-ordinate complexes of the above ligands with palladium(II) and platinum(II) halides and cyanides have also been prepared, and their structures in solution examined by 1H nmr spectroscopy The complex phos2 PtCl2(phos = 9-methyl-9-phosphafluorene) has the cis-configuration in trifluoroacetic acid solution, whereas the corresponding platinum and palladium cyanide complexes have the trans-configuration9-Phenyl-9-phosphafluorene (I; R = Ph) resembles triphenylphosphine in forming only normal four-co-ordinate complexes with the above metal halidesIt is suggested that unusual co-ordinating ability of the 9-alkyl-9-phosphafluorenes [and of 2-phenylisophosphindoline (III) which also forms a similar series of complexes] is due to a favourable combination of both steric and electronic (donor–acceptor) propertiesPreliminary experiments show that 10-methylphenoxaphosphine (VI; R = Me) also forms similar five-co-ordinate complexes, but the 10-phenyl analogue forms only four-co-ordinate complexes
11 citations
TL;DR: Dicyanotris-(9-methyl-9-phosphafluorene)nickel(II) as discussed by the authors has tetragonal pyramidal and trigonal bipyramidal configurations in the solid state.
Abstract: Dicyanotris-(9-methyl-9-phosphafluorene)nickel(II) and dicyanotris-(9-ethyl-9-phosphafluorene)nickel(II) have tetragonal pyramidal and trigonal bipyramidal configurations, respectively, in the solid state, though in solution they have the same structure.
6 citations