Silica Gel as a Promoter of Sequential Aza-Michael/Michael Reactions of Amines and Propiolic Esters: Solvent- and Metal-Free Synthesis of Polyfunctionalized Conjugated Dienes
and solvent‐free silica‐gel‐promoted synthesis of functionalized conjugated dienes by sequential aza‐Michael/Michael reactions by starting from commercially available primary amines and propiolic esters. The scope and usefulness of the method is demonstrated for 31 examples, including a range of propiolic esters, aliphatic amines, and differently substituted aromatic amines. For aliphatic amines, the
The reactions of Boc-β-amido- and β-amino acrylates, in which the CC possesses both nucleophilic and electrophilic sites, were investigated under acidic conditions. The trifluoroacetic-acid induced cyclization of the β-amido acrylates to the corresponding oxazolidin-2-ones involves a rarely seen nucleophilic attack of the carbamate carbonyl group. The cyclotrimerization of β-amino acrylates to N-substituted
An organocatalytic multi-molecular cascade reaction for the synthesis of acetate functionalized 1,4-dihydropyridines
作者:Deqing Hu、Yunyun Liu、Jie-Ping Wan
DOI:10.1016/j.tet.2015.06.101
日期:2015.9
An organocatalytic cascade reaction involving the incorporation of alkyl propiolates and primary amines has been realized for the facile synthesis of 1,4-dihydropyridines (1,4-DHPs) bearing a C4 acetate fragment. This method allows rapid and atom economical generation of N-aryl, N-alkyl, and NH 1,4-DHPs with moderate to excellent yields. (C) 2015 Elsevier Ltd. All rights reserved.