Chemo-enzymatic synthesis of new ferrocenyl-oxazolidinones and their application as chiral auxiliaries

A chemo-enzymatic synthesis of new chiral ferrocenyl-oxazolidinones has been developed. The key step was the addition of HCN to formylferrocene catalysed by the hydroxynitrile lyase from Hevea brasiliensis, which yielded an enantiomerically pure ferrocenyl-cyanohydrine in excellent yield and ee. The ferrocenyl-oxazolidinones obtained by this strategy were tested as chiral auxiliaries for asymmetric alkylations and aldol reactions and were shown to be effective in terms of yields, stereoselectivities and cleavage conditions. (C) 2008 Elsevier Ltd. All rights reserved.