Synthesis of N-Heterocycles by Reductive Cyclization of Nitroalkenes using Molybdenum Hexacarbonyl as Carbon Monoxide Surrogate

The development of a method that uses molybdenum hexacarbonyl [Mo(CO)(6)] as carbon monoxide (CO) surrogate for the palladium-catalyzed reductive cyclization of nitroalkenes into indoles or thienopyrroles is reported. Several types of nitroalkenes could be transformed into the desired products in excellent yields and in most cases with complete regioselectivities and higher yields than those previously reported with palladium/CO system.