Remote Meta-C-H Activation Using a Pyridine-Based Template: Achieving Site-Selectivity via the Recognition of Distance and Geometry.

ABSTRACT: The pyridyl group has been extensively employed to direct transition-metal-catalyzed C-H activation reactions in the past half-century. The typical cyclic transition states involved in these cyclometalation processes have only enabled the activation of ortho-C-H bonds. Here, we report that pyridine is adapted to direct meta-C-H activation of benzyl and phenyl ethyl alcohols through engineering the distance and geometry of a directing template. This template takes advantage of a stronger ?-coordinating pyridine to recruit Pd catalysts to the desired site for functionalization. The U-shaped structure accommodates the otherwise highly strained cyclophane-like transition state. This development illustrates the potential of achieving site selectivity in C-H activation via the recognition of distal and geometric relationship between existing functional groups and multiple C-H bonds in organic molecules.

SUBMITTER: Chu L 

PROVIDER: S-EPMC4827496 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature