synthesizing different functionalized isoxazoles is provided. Carbamoylnitrile oxide generated from nitroisoxazolone underwent inverse electron-demand 1,3-dipolarcycloaddition with 1,3-dicarbonyl compounds in the presence of magnesium acetate that formed magnesium enolate in situ. Although electron-deficient trifluoroacetoacetate did not undergo this cycloaddition under the same conditions, conversion
Base- and Copper-Catalysed Condensation of Primary Activated Nitro Compounds with Enolisable Compounds
作者:Elena Trogu、Luca Cecchi、Francesco De Sarlo、Luca Guideri、Fabio Ponticelli、Fabrizio Machetti
DOI:10.1002/ejoc.200900802
日期:2009.12
Primarynitrocompounds have not been employed as nitrile oxide precursors in reactions with active methylene compounds because the reagents commonly used as dehydrating agents also react with these dipolarophiles. However, the CuII-catalysed cycloaddition/condensation procedure has been shown to be viable with these substrates, leading directly to the expected polyfunctional isoxazoles provided nitro