Sulfoxides and Stereochemical Control in Organometallic Chemistry

The sulfinyl substituted oxadienes (RS(O)CH=CHC(Me)=O; R = But, Ph) form stable diastereoisomerically pure tricarbonyliron(0) complexes, the relative stereochemistry of which was determined by X-ray crystal structure analysis. Phenylsulfinylethene forms a stable tetracarbonyliron(0) complex which is also diastereoisomerically pure. An X-ray crystal structure analysis of this complex revealed its relative stereochemistry and evidence for a through-space interaction between the oxygen atom of the sulfinyl substituent and the carbon atom of one of the metal carbonyl ligands. Dimethyldioxirane efficiently oxidises tricarbonylchromium(0) complexes of sulfenyl substituted arenes to tricarbonylchromium(0) complexes of sulfinyl substituted arenes. The diastereoselectivity of the oxidation of ortho substituted complexes was determined and found to be dramatically reversed when the sulfenyl substituent is changed from methyl to tea-butyl.