Catalytic 1,4-rhodium(III) migration enables 1,3-enynes to function as one-carbon oxidative annulation partners in C-H functionalizations

David J Burns; Hon Wai Lam

doi:10.1002/anie.201406072

Catalytic 1,4-rhodium(III) migration enables 1,3-enynes to function as one-carbon oxidative annulation partners in C-H functionalizations

Angew Chem Int Ed Engl. 2014 Sep 8;53(37):9931-5. doi: 10.1002/anie.201406072. Epub 2014 Jul 22.

Authors

David J Burns¹, Hon Wai Lam

Affiliation

¹ School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD (UK) http://www.nottingham.ac.uk/∼pczhl.

Abstract

1,3-Enynes containing allylic hydrogens cis to the alkyne are shown to act as one-carbon partners, rather than two-carbon partners, in various rhodium-catalyzed oxidative annulations. The mechanism of these unexpected transformations is proposed to occur through double C-H activation, involving a hitherto rare example of the 1,4-migration of a Rh(III) species. This phenomenon is general across a variety of substrates, and provides a diverse range of heterocyclic products.

Keywords: CH functionalization; catalysis; enyne; oxidation; rhodium.