Metallacyclic platinum(II) bis(sulfonamides)

Abstract

A series of metallacyclic platinum(II) bis(sulfonamido) complexes have been synthesised by reaction of cis-[PtCl 2L 2] [L=PPh 3 or L 2=1,5- cyclo-octadiene (cod)] with the sulfonamides [RSO 2NHCH 2CH 2NHSO 2R, RSO 2NHCH 2CHMeNHSO 2R or RSO 2NHC 6H 4NHSO 2R; R=Ph or p-C 6H 4Me] and Ag 2O. The products have been characterised by NMR spectroscopy, electrospray mass spectrometry, elemental analysis, and for the complexes [ Pt{N(SO 2Ph)CH 2CH 2N (SO 2Ph)}(PPh 3) 2] and [ Pt{N(SO 2Ph)C 6H 4N (SO 2Ph)}(cod)], by single-crystal X-ray structure determinations. In both of these complexes, one of the amido nitrogen atoms has the expected approximately planar geometry, but the other nitrogen atom is surprisingly distorted towards a tetrahedral geometry. The more pyramidal nitrogen has a higher trans-influence in the solid state, reflected by a shorter PtN bond, and longer cyclo-octadiene PtC bond length trans to this nitrogen.