An efficient and high-yielding one-pot synthesis of 4-acyl-1,2,3-triazoles via triisopropylsilyl-protected ynones
摘要:
A practical and efficient process has been developed for the synthesis of 1-substituted 4-acyl-1H-1,2,3-triazoles using a three-step one-pot synthetic approach. This transformation involves an initial preparation of triisopropylsilyl (TIPS)-protected ynones from acid chlorides and TIPS-acetylene, followed by a AgF-mediated TIPS deprotection and Cu-catalyzed Huisgen cycloaddition. The increased chemical stability of TIPS-protected ynones was an important factor in the high overall product yield. (C) 2011 Elsevier Ltd. All rights reserved.
A copper-catalyzed three-component reaction of methyl ketones, organic azides, and various one-carbon (C1) donors was developed that provides 4-acyl-1,2,3-triazoles in moderate to good yields. While DMF, DMA, TMEDA, or DMSO can serve as the C1 donor, best yields were obtained using DMF. The transformation is proposed to proceed via an oxidative C–H/C–H cross-dehydrogenative coupling followed by an