Thieme E-Journals - Synlett / Abstract
Recommend Article Subscribe to Alert Service
Synlett 2019; 30(13): 1496-1507
DOI: 10.1055/s-0037-1611878
synpacts
© Georg Thieme Verlag Stuttgart · New York

Visible-Light Reductive Cyclization of Nonactivated Alkyl Chlorides

Authors

  • Miguel Claros

    a   Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology,
    Avda. Països Catalans, 16, 43007, Tarragona,
    Spain   
    b   University Rovira i Virgili (URV) department of physical and inorganic chemistry,
    C/Marcel·lí Domingo, 43007 Tarragona, Catalonia,
    Spain
  • Alicia Casitas

    c   Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Campus de Montilivi,
    17003 Girona, Catalonia,
    Spain   
  • Julio Lloret-Fillol

    a   Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology,
    Avda. Països Catalans, 16, 43007, Tarragona,
    Spain   
    d   Catalan Institution for Research and Advanced Studies (ICREA),Passeig Lluïs Companys,
    23, 08010, Barcelona,
    Spain

We acknowledge the financial support from the ICIQ Foundation and MINECO (CTQ2016-80038-R) to J. Ll.-F.


Graphical Abstract

Abstract

Nonactivated alkyl chlorides are readily available and bench-stable feedstocks; however, they exhibit an inherent chemical inertness, in part, due to their large negative reduction potentials, which have precluded their widespread use as radical precursors in visible-light photocatalysis. Herein, we highlight some recent strategies for activating challenging organic halides under light irradiation, with special emphasis in C(sp3)–halide bonds. In this line, a brief summary of the reactivity of Vitamin B12, F430 cofactor and derivatives is required to comprehend the chemistry behind our developed Cu/M (M = Co, Ni) dual catalytic system. Catalyst design has been key for developing a mild and general photoredox methodology for the intramolecular reductive cyclization of nonactivated alkyl chlorides with tethered alkenes. The cleavage of strong C(sp3)–Cl bonds is mediated by a highly nucleophilic low-valent cobalt or nickel intermediate generated by visible-light photoredox reduction employing a copper photosensitizer.