The first enantioselective synthesis of isoflavonoids: (R)- and (S)-isoflavans
Abstract
α-Benzylation of (+)- and (–)-N-phenylacetyl imidazolidinones with 2-O-methoxymethylbenzyl bromide, followed by reductive removal of the chiral auxiliary and cyclization, leads to isoflavans in excellent enantiomeric excess and yield.