Dinuclear thiazolylidene copper complex as highly active catalyst for azid-alkyne cycloadditions

作者:Schoeffler Anne L; Makarem Ata; Rominger Frank; Straub Bernd F*
来源:Beilstein Journal of Organic Chemistry, 2016, 12: 1566-1572.
DOI:10.3762/bjoc.12.151

摘要

A dinuclear N-heterocyclic carbene (NHC) copper complex efficiently catalyzes azide-alkyne cycloaddition (CuAAC) "click" reactions. The ancillary ligand comprises two 4,5-dimethyl-1,3-thiazol-2-ylidene units and an ethylene linker. The three-step preparation of the complex from commercially available starting compounds is more straightforward and cost-efficient than that of the previously described 1,2,4-triazol-5-ylidene derivatives. Kinetic experiments revealed its high catalytic CuAAC activity in organic solvents at room temperature. The activity increases upon addition of acetic acid, particularly for more acidic alkyne substrates. The modular catalyst design renders possible the exchange of N-heterocyclic carbene, linker, sacrificial ligand, and counter ion.

  • 出版日期2016-7-21