A mild copper-mediated Glaser-type coupling reaction under the novel CuI/NBS/DIPEA promoting system

A simple copper promoting system CuI/NBS/DIPEA was first found to efficiently promote Glaser coupling reaction under ambient temperature. The alkynes with sensitive groups such as acetal and ketal, TBDMS, ester and amide could react smoothly to afford the functionalized 1,3-diynes under the CuI/NBS/DIPEA promoting system in good yields. And the successful application of the Cul/NBS/DIPEA promoting system in sugar and amino acid-building blocks indicated the potential of this method in the construction of designed sugar and peptide biomolecules. (C) 2009 Published by Elsevier Ltd.