Trans-Hydrometalation of Alkynes by a Combination of InCl3 and DIBAL-H:  One-Pot Access to Functionalized (Z)-Alkenes

reaction: see text Triethylborane-induced hydrometalation of alkynes proceeds in an anti manner to afford the corresponding (Z)-alkenylmetal compounds stereoselectively, where dichloroindium hydride would play a key role. A variety of functional groups including hydroxy, carbonyl, and carboxy groups were tolerant under the reaction conditions. Following iodolysis and cross-coupling reaction of the (Z)-alkenylmetal species show the usefulness of this strategy.