Single-step construction of an acetoxypyrroloindole skeleton via tandem iodocyclization/acetoxylation of indoles

A method for the synthesis of C3a acetoxy hexahydropyrrolo[2,3-b]indole derivatives via a PhI(OAc)2/nBu4NI mediated tandem iodocyclization/acetoxylation has been developed. The newly developed synthetic strategy features the single-step assembly of various C3a acetoxylated tetrahydropyrrole-, tetrahydrofuran-, and lactone-fused indolines under mild reaction conditions, which enabled efficient asymmetric synthesis of (-)-protubonine B.