Enantioselective dialkylation of 1,2-phthalicdicarboxaldehyde

A new two-step, one-pot procedure is reported for the enantioselective synt hesis of C-2-symmetric diols derived from 1,2-phthalicdicarboxaldehyde. The first step involves the enantioselective addition of a dialkylzine compoun d to one of the aldehyde groups, affording a lactol organozine derivative. In the second step this lactol derivative is converted to the appropriate d iol with the aid of a Grignard reagent and subsequent hydrolysis. This meth odology also allows the synthesis of unsymmetric diols. (C) 2001 Elsevier S cience Ltd. All rights reserved.