Overriding Intrinsic Reactivity in Aliphatic C-H Oxidation: Preferential C3/C4 Oxidation of Aliphatic Ammonium Substrates

Abstract

The site-selective C-H oxidation of unactivated positions in aliphatic ammonium chains poses a tremendous synthetic challenge, for which a solution has not yet been found. Here, we report the preferential oxidation of the strongly deactivated C3/C4 positions of aliphatic ammonium substrates by employing a novel supramolecular catalyst. This chimeric catalyst was synthesized by linking the well-explored catalytic moiety Fe(pdp) to an alkyl ammonium binding molecular tweezer. The results highlight the vast potential of overriding the intrinsic reactivity in chemical reactions by guiding catalysis using supramolecular host structures that enable a precise orientation of the substrates.

Keywords: C−H oxidation; catalysis; molecular recognition; regioselectivity; supramolecular chemistry.