Synthesis of 2,3,5-trisubstituted furans from α-formylaroylketene dithioacetals

A new strategy for the synthesis of 2,3,5-trisbustituted furans from α-formylketene dithioacetals is described. The protocol involves a facile conversion of α-formylketene dithioacetals to vinylketene dithioacetals via Wittig reaction and subsequent N-bromosuccinimide-mediated cyclization to 2,3,5-trisbustituted furans. Further conversion of the 2-thioalkylfurans thus obtained to 2-aminofurans shows the potential synthetic utility of this new approach.