Stereoselective Preparation of Polyfunctional Alkenylindium(III) Halides and Their Cross-Coupling with Unsaturated Halides.

The direct insertion of indium powder to cycloalkenyl iodides in the presence of LiCl in THF allows the preparation of new highly functionalized cycloalkenylindium(III) derivatives. In addition, we discovered that, in contrast to many metal insertions to alkenyl iodides which proceed with a loss of stereochemistry, the insertion of In/LiCl to stereodefined (Z)- and (E)-styryl iodides in THF proceeded with high retention of stereochemistry. After a palladium-catalyzed cross-coupling, various polyfunctionalized (Z)- and (E)-stilbenes were obtained with high stereoselectivity.