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Biphilic Organophosphorus Catalysis: Regioselective Reductive Transposition of Allylic Bromides via P(III)/P(V) Redox Cycling.

ABSTRACT: We report that a regioselective reductive transposition of primary allylic bromides is catalyzed by a biphilic organophosphorus (phosphetane) catalyst. Spectroscopic evidence supports the formation of a pentacoordinate (?(5)-P) hydridophosphorane as a key reactive intermediate. Kinetics experiments and computational modeling are consistent with a unimolecular decomposition of the ?(5)-P hydridophosphorane via a concerted cyclic transition structure that delivers the observed allylic transposition and completes a novel P(III)/P(V) redox catalytic cycle. These results broaden the growing repertoire of reactions catalyzed within the P(III)/P(V) redox couple and suggest additional opportunities for organophosphorus catalysis in a biphilic mode.

SUBMITTER: Reichl KD

PROVIDER: S-EPMC4769643 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Biphilic Organophosphorus Catalysis: Regioselective Reductive Transposition of Allylic Bromides via P(III)/P(V) Redox Cycling.

Reichl Kyle D KD Dunn Nicole L NL Fastuca Nicholas J NJ Radosevich Alexander T AT

Journal of the American Chemical Society 20150421 16

We report that a regioselective reductive transposition of primary allylic bromides is catalyzed by a biphilic organophosphorus (phosphetane) catalyst. Spectroscopic evidence supports the formation of a pentacoordinate (σ(5)-P) hydridophosphorane as a key reactive intermediate. Kinetics experiments and computational modeling are consistent with a unimolecular decomposition of the σ(5)-P hydridophosphorane via a concerted cyclic transition structure that delivers the observed allylic transpositio ...[more]

PMID: 25874950

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