Construction of Optically Active 2H- and 3H-Pyrroles by Cyclization and Chirality Maintaining 1,5-Ester Shift Reactions

Construction of enantioenriched 2H- and 3H-pyrroles are achieved in current work by using readily available alpha-isocyanoacetates and alkynyl ketones as precursors. To realize the asymmetric synthesis of 2H-pyrroles, a proper in situ generated magnesium catalytic method was developed. On the other hand, the discovery of an aluminium mediated chirality maintaining 1,5-ester shift reaction promoted the successful synthesis of enantioenriched 3H-pyrroles.