Synthesis of (<i>E</i>)-α,β-Unsaturated Carbonyls<i>via</i>Silver-Catalyzed Tandem Epoxide Rearrangement/Intermolecular Carbonyl- Heteroalkyne Metathesis
stereoselective method for the synthesis of (E)‐α,β‐unsaturated carbonyls has been developed via a silver‐catalyzed tandem epoxide rearrangement/intermolecular carbonyl‐heteroalkyne metathesis. Various heteroalkynes including ynol ethers, ynamides, and thioalkynes work well for this transformation, leading to the production of (E)‐α,β‐unsaturatedesters, amides, and thioesters in moderate to excellent
A convenient titanium-mediated intermolecular alkyne–carbonate coupling reaction
作者:Andrzej Wolan、Frédéric Cadoret、Yvan Six
DOI:10.1016/j.tet.2009.07.015
日期:2009.9
A direct diastereoselective titanium-mediated intermolecular coupling of internal alkynes with dialkyl carbonates under Kulinkovich-type reaction conditions is presented. The influence of the structures of the coupling partners on the yields and regioselectivities of this transformation is described. (C) 2009 Elsevier Ltd. All rights reserved.