Phosphanyl-Amino Complexes of Nickel(II): Synthesis and Structure

New neutral pentacoordinate nickel(II) complexes of the type [NiCl<INF>2</INF>(PR<INF>3</INF>)(P^∩N)] [PR<INF>3</INF> = PMe<INF>3</INF>, PMe<INF>2</INF>Ph, PMePh<INF>2</INF>; P^∩N = 2-(diphenylphosphanyl)aniline (P^∩NH<INF>2</INF>), N-methyl-2-(diphenylphosphanyl)aniline (P^∩NHMe), N,N-dimethyl-2-(diphenylphosphanyl)aniline (P^∩NMe<INF>2</INF>)], as well as cationic tetracoordinate nickel(II) complexes of the type [NiCl(PR<INF>3</INF>)(P^∩N)]⁺ have been synthesized and characterized both in the solid state and in solution. Interesting X-ray structural data have been collected for each class of compounds, which show, inter alia, that the pentacoordinate neutral complexes can be isolated in two different molecular forms, namely square-pyramidal or bipyramidal-trigonal.