Microwave-Assisted or Cu-NHC-Catalyzed Cycloaddition of Azido-Disubstituted Alkynes: Bifurcation of Reaction Pathways

作者:Xia Yuyu; Chen Ling yan; Lv Shang; Sun Zhihua*; Wang Bing
来源:Journal of Organic Chemistry, 2014, 79(20): 9818-9825.
DOI:10.1021/05011262

摘要

Microwave irradiation promoted the intramolecular cycloaddition of 2-azidoacetamides derived from a-chiral propargylic amines, affording 1,4,5-trisubstituted triazoles 4 bearing a chiral aminomethyl side chain at C5. In contrast, for the same substrates 3a-k, Cu(I)-NHC complexes catalyzed the intermolecular cycloaddition in an unexpected desilylative fashion, leading to 1,4-disubstituted triazoles 5. This demonstrates that 1-silyl alkynes can be employed as substrates for CuAAC with a suitable coupling partner.