The first total synthesis of cryptopyranmoscatones A3 and B4 has been accomplished from d-ribose or but-3-ynol. The key steps involved in the synthesis are oxa-Michael addition, highly diastereoselective Brown allylation, and ring closing metathesis (RCM) and cross metathesis (CM) reactions.
Key words
oxa-Michael addition - Brown asymmetric allylation - ring-closing metathesis - cross metathesis