The method employing dimolybdenum tetraacetate for the assignment of the absolute configuration of optically active 1,2-diols is thoroughly revisited and applied to several compounds, some of which were synthesized by asymmetric cis-dihydroxylation. No exceptions were found to the empirical rule relating the sign of the induced CD spectrum and the configuration of the substrate, whatever its structure and sterical requirements. To broaden the scope of the method, its applicability to critical situations commonly encountered 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 content of the sample and of the diol-to-dimolybdenum ratio are investigated.

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A convenient route for the covalent immobilization of quinidine and hydroquinidine pyridazine ethers on\ud \ud insoluble polystyrene supports is described, which avoids the need of chromatographic purifications at any stage.\ud \ud The use of the heterogeneized alkaloid derivatives in the asymmetric organocatalytic dimerization of ketenes\ud \ud afforded high enantioselectivity values (90-97% ee) in the course of 20 reaction cycles