Stereoselective nucleophilic additions to 9,10-anthraquinone. Comparison of grignard and sulphur ylide additions

Abstract

Analysis of long-range ¹H n.m.r. shielding effects has provided insight into the conformational behaviour of the products of single and double addition of dimethylsulphonium methylide to 9,10-anthraquinone. This information is consistent with a double addition reaction in which stereospecificity arises, at least in part, from a directing effect exerted by oxiran oxygen on the entering ylide.