Catalytic divergent synthesis of 3H or 1H pyrroles by [3 + 2] cyclization of allenoates with activated isocyanides.

The cyclization of allenoates with activated isocyanides was reported for the first time. While Ag catalysis led to an unprecedented enantioselective synthesis of 3H pyrroles, a simple procedure using PPh3 produced a wide range of polysubstituted 1H pyrroles with high efficiency.