Mechanistic studies revealed that the benzylic radical could be trapped by TEMPO and DPE, indicating the involvement of a radical in the reaction mechanism (Figure ). The equilibrium between intermediates 11.6 and 11.6', which appeared independent of the Cu(I)-BINAP catalyst or base and occurred in the presence of heat (Figure ), both led to the same product 11.8 in the "one-pot" setup, thus supporting the regioconvergent nature of the reaction (Figure ). Cross-over experiments and O labeling studies suggested an intramolecular mode of acyloxy migration proceeding through a five-membered transition state 11.18 (Figure ). The proposed mechanism involves the single-electron transfer (SET) reduction of 11.6' by the excited-state Cu(I)-BINAP complex, yielding intermediate 11.21, which subsequently adds to a silyl enol ether coupling partner to form 11.22. This intermediate is then oxidized by Cu(II) species and desilylated by Na2CO3, affording the desired β-acyloxyketonylstyrene product (Figure ).