Short synthesis of noscapine, bicuculline, egenine, capnoidine, and corytensine alkaloids through the addition of 1-siloxy-isobenzofurans to imines

A concise diastereoselective strategy for the syntheses of several isoquinoline alkaloids was developed via a divergent route by the addition of 1-siloxy-isobenzofurans 4a and 4b to iminium 5 in a one-pot approach.