Selective Isomerization of a Terminal Olefin Catalyzed by a Ruthenium Complex: The Synthesis of Indoles through Ring‐Closing Metathesis

Abstract

A ruthenium complex, generated from the Grubbs carbene catalyst with vinyloxytrimethylsilane, catalyzed the isomerization of terminal alkenes RCH2CHCH2 to internal alkenes RCHCHCH3. Application of this olefin isomerization to 2-(N-allylamino)styrene gave the corresponding enamines, which were converted into indoles by a standard ring-closing metathesis, see scheme (Ts=tosyl).