Determination of absolute configuration of acyclic 1,2-diols with Mo-2(OAc)(4). 1. Snatzke's method revisited

The method employing dimolydbenum tetraacetate for the assignment of the ab solute configuration of optically active 1,2-diols is thoroughly revisited and applied to several compounds, some of which were synthesized by asymmet ric cis-dihydroxylation. No exceptions were found to the empirical rule rel ating the sign of the induced CD spectrum and the configuration of the subs trate, whatever its structure and sterical requirements. To broaden the sco pe of the method, its applicability to critical situations commonly encount ered with synthetic products is tested. It is demonstrated that the method can be applied on samples with low chemical and optical purity, and that it may lend itself as a means to estimate the ee. The roles of the water cont ent of the sample and of the diol-to-dimolybdenum ratio are investigated.