Premium
Supramolecular Recognition Allows Remote, Site‐Selective C−H Oxidation of Methylenic Sites in Linear Amines
Author(s) -
Olivo Giorgio,
Farinelli Giulio,
Barbieri Alessia,
Lanzalunga Osvaldo,
Di Stefano Stefano,
Costas Miquel
Publication year - 2017
Publication title -
angewandte chemie international edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 1433-7851
DOI - 10.1002/anie.201709280
Subject(s) - oxidizing agent , chemistry , supramolecular chemistry , reactivity (psychology) , selectivity , crown ether , protonation , catalysis , hydrogen bond , hydroxylation , alkyl , ether , combinatorial chemistry , medicinal chemistry , stereochemistry , molecule , organic chemistry , enzyme , ion , medicine , alternative medicine , pathology
Site‐selective C−H functionalization of aliphatic alkyl chains is a longstanding challenge in oxidation catalysis, given the comparable relative reactivity of the different methylenes. A supramolecular, bioinspired approach is described to address this challenge. A Mn complex able to catalyze C(sp 3 )‐H hydroxylation with H 2 O 2 is equipped with 18‐benzocrown‐6 ether receptors that bind ammonium substrates via hydrogen bonding. Reversible pre‐association of protonated primary aliphatic amines with the crown ether selectively exposes remote positions (C8 and C9) to the oxidizing unit, resulting in a site‐selective oxidation. Remarkably, such control of selectivity retains its efficiency for a whole series of linear amines, overriding the intrinsic reactivity of C−H bonds, no matter the chain length.