Crystal structure and catalytic activity of ruthenium (II)/dithiocarbamate complexes in the epoxidation of cyclooctene

Abstract

Complexes with the general formula [Ru(dppb)(R)2] {where: dppb=1,4-bis(diphenylphosphino)butane and R=piperidinedithiocarbamate (pipeCS2−) (1); morpholinedithiocarbamate (morphCS2−) (2); ethilenodiaminedithiocarbamate (ethCS2−) (3) and hexamethilenominedithiocarbamate (hexCS2−) (4)} were synthesised from [RuCl2(dppb)]2-μ-(dppb). The complexes were characterised by nuclear magnetic resonance of phosphorus (31P{1H} NMR), cyclic voltammetry (CV) as well as elemental analyses. The X-ray structures of (1), (2), and (3) were determined and are presented here. Additionally, the complexes (1–4) were used as pre-catalysts in the epoxidation of cyclooctene, and initial results show that complex (4) has a selectivity of 74% in the epoxide product, with 53% conversion. The epoxidation catalysed used iodosylbenzene (PhIO) as primary oxidant.