Synlett 2019; 30(01): 94-98
DOI: 10.1055/s-0037-1610342
letter
© Georg Thieme Verlag Stuttgart · New York

Toluene and its Derivatives as Atom-Efficient Benzylating Agents for Secondary Amines

David Schönbauer
,
Florian Lukas
,
Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-OC, Vienna 1060, Austria   Email: michael.schnuerch@tuwien.ac.at
› Author Affiliations
Further Information

Publication History

Received: 30 October 2018

Accepted after revision: 05 November 2018

Publication Date:
04 December 2018 (online)

Abstract

Toluene as a replacement for common N-benzylating agents, such as benzyl bromide, can be an atom-efficient alternative reagent. Under nickel catalysis and mildly oxidative conditions, it is possible to activate toluene efficiently and use it directly for the benzylation of different 2-aminopyridines. The transformation is not restricted to simple toluene, but also substituted derivatives give the desired product in good yields. Effective cleavage of the pyridine moiety is presented.

Supporting Information

 
  • References and Notes

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