Rh(II)-Catalyzed C–H Alkylation of Benzylamines with Unactivated Alkenes: The Influence of Acid on Linear and Branch Selectivity

Abstract

The Rh-catalyzed C−H alkylation of benzylamine derivatives with unactivated 1-alkenes that proceeds via a picolinamide directing group is reported. The crucial role of an acid additive in this transformation is confirmed. Aromatic acids showed high linear selectivity, and aliphatic acids provided branched alkylation products as the major product. The reaction has a broad scope for benzylamines and alkenes. Deuterium labeling experiments suggest that a Rh-carbene intermediate is involved in the case of linear product formation. A different reaction pathway, however, appears to be involved in the case of branched alkylation products, and this pathway also appeared to be a minor pathway in linear-selective reactions.

Transition-metal-catalyzed C–H bond alkylation using olefins: recent advances and mechanistic aspects

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An Unusual Perpendicular Metallacycle Intermediate is the Origin of Branch Selectivity in the Rh(II)-Catalyzed C–H Alkylation of Aryl Sulfonamides with Vinylsilanes

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Methylene Thiazolidinediones as Alkylation Reagents in Catalytic C–H Functionalization: Rapid Access to Glitazones

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