Abstract
The functionalization of etheric C-O bonds via C-O bond cleavage is an attractive strategy for the construction of C-C and C-X bonds in organic synthesis. However, these reactions mainly involve C(sp(3))-O bond cleavage, and a catalyst-controlled highly enantioselective version is extremely challenging. Here, we report a copper-catalyzed asymmetric cascade cyclization via C(sp(2))-O bond cleavage, allowing the divergent and atom-economic synthesis of a range of chromeno[3,4-c]pyrroles bearing a triaryl oxa-quaternary carbon stereocenter in high yields and enantioselectivities. Importantly, this protocol not only represents the first [1,2]-Stevens-type rearrangement via C(sp(2))-O bond cleavage, but also constitutes the first example of [1,2]-aryl migration reactions via vinyl cations.