Synthesis of Functionalized Biaryls Based on a Heck Cross-Coupling-[3+3] Cyclization Strategy
作者:Peter Langer、Gerson Mroß、Helmut Reinke
DOI:10.1055/s-2008-1072654
日期:——
6-Arylsalicylates were regioselectively prepared by formal [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with 1-aryl-3-ethoxyprop-2-en-1-ones which are available by Heck reaction of benzoyl chlorides with ethylvinyl ether. In this context, the first [3+3] cyclizations of brominated substrates are reported.
The formal [3+3] cyclization of 1,3-bis(silyloxy)buta-1,3-dienes with 1-aryl-3-ethoxyprop-2-en-1-ones, available by Heck reaction of benzoyl chlorides with ethyl vinyl ether, afforded a variety of 6-arylsalicylates. The reaction of the products with concentrated sulfuric acid resulted in the formation of fluorenones. 6-Alkylsalicylates were prepared by cyclization of 1,3-bis(silyloxy)buta-1,3-dienes
Transition-Metal-Free Benzannulation for Diverse and Polyfunctionalized Biaryl Formation
作者:Tej Narayan Poudel、Yong Rok Lee
DOI:10.1021/acs.orglett.5b00996
日期:2015.5.1
transition-metal-free benzannulation was achieved in good yield from readily available β-ketoesters, β-ketoamides, or 1,3-diketones with cinnamaldehydes or aryl aldehydes. This transformation comprises a sequence of the formation of three new bonds through multicomponent reactions as a one-pot procedure. This novel biaryl formation proceeds through domino Michael addition/intramolecular and intermolecular aldol/[1