摘要:
An interesting phosphine-containing Lewis base catalyzed highly regioselective [3 + 2] cycloaddition and a novel nitrogen-containing Lewis base catalyzed highly geometric selective [4 + 2] cycloaddition of isatin derived alpha,beta-unsaturated diesters with alpha-allenic ester have been disclosed to give the corresponding cyclic products in good to excellent yields under mild conditions. A plausible reaction mechanism has also been proposed on the basis of previous literature and our own investigation.