2,2′-Bipyridine-3,3′-dicarboxylic carbohydrate esters and amides. Synthesis and preliminary evaluation as ligands in Cu(II)-catalysed enantioselective electrophilic fluorination

A series of 10 new carbohydrate-substituted bipyridines were prepared from 2,2'-bipyridine-3,3'-dicarboxylic acid, itself easily available from ortho-phenanthroline. As a preliminary exploration of their use as chiral ligands, Cu(II)-catalysed asymmetric electrophilic fluorination of model beta-ketoesters using these simple and easily accessible chiral bipyridines was studied. Only modest enantioselectivity was observed in this reaction, although the ee was in a similar range as those provided by known and more elaborate ligands. (C) 2009 Elsevier Ltd. All rights reserved.