Rh(III)-Catalyzed Stereoselective C–H Homoallylation of Indolines with 4-Vinyl-1,3-dioxan-2-ones

Abstract

An efficient and robust Rh(III)-catalyzed C−H homoallylation of indolines has been developed. Using 4-vinyl-1,3-dioxan-2-one as coupling parnter, a range of homoallylic alcohols could be prepared in excellent stereoselectivities. The current strategy exhibits high efficiency, good yields, and exceptional functional group tolerance.

Rh-catalyzed ring-opening coupling of cyclic vinyl ethers with organometallic reagents

“…The reaction begins with transmetalation between the rhodium catalyst and the organometallic reagent to form intermediate A . 18 In the case of 2,3-dihydrofuran, syn insertion with A takes place to generate intermediate B , 19 which may undergo antiperiplanar β-oxygen elimination 20 to give the Z -selective ring-opening alkoxorhodium product. The alkoxorhodium species then reacts with organoboron to regenerate A , thus closing the catalytic cycle.…”