posted on 2020-03-06, 14:38authored byKaixiu Luo, Shuai Mao, Kun He, Xianglin Yu, Junhong Pan, Jun Lin, Zhihui Shao, Yi Jin
An
efficient [4+1C]insert approach to the coupling of
enaminones with donor/acceptor or donor/donor carbenes by the AgOTf-catalyzed
C–C bond carbenoid formal insertion/cyclization/[1,5]-shift
cascade reaction was successfully developed, providing distinct chemo-
and regioselective multisubstituted pyrroles. The plausible reaction
mechanism involves two catalytic cycles: in the first one, silver
ions regioselectively catalyze the C–C bond formal insertion
reaction; in the second one, silver ions chemo- and regioselectively
control the cyclization and [1,5]-shift reactions. This method not
only provides convenience and applies atom economy in the synthesis
of multisubstituted pyrroles but also presents an entry point for
further pyrrole diversification via facile modification of resulting
4H-pyrrole products, as displayed by a short formal
synthesis of the natural product lamellarin L.