Intramolecular radical trapping in “set” ring opening of N-enoyl aziridines. A new mechanistic probe and a new synthesis of pyrrolidones.
作者:G. Bentz、N. Besbes、A. Laurent、H. Stamm
DOI:10.1016/s0040-4039(00)95454-6
日期:1987.1
N-Acryloyl aziridines 1a-c form pyrrolidones 4a-c via electron attachment, homolytic ring cleavage of the intermediate ketyl, and intramoleculartrapping of the radical by the CC bond of the acryloyl moiety of 1a-c.
Cyclisation at very high temperature. Thermal transformations of N-alkyl and N, N-dialkyl amides of α,β-unsaturated acids into mono- and bicyclic heterocycles under FVT conditions
作者:Stanisław Leśniak、Ryszard B. Nazarski、Beata Pasternak
DOI:10.1016/j.tet.2009.06.011
日期:2009.8
Cyclisations of N-alkyl and N,N-dialkyl cinnamic amides to the corresponding pyrrolidin-2-ones under the conditions of flash vacuum thermolysis (FVT), are described. It was found that these reactions proceed at 950-1000 degrees C affording in various yields the mixtures of isomeric mono and bicyclic gamma-lactams, which were separated chromatographically and analysed by means of NMR spectroscopy. Two alternative mechanisms for the title process are proposed. (C) 2009 Elsevier Ltd. All rights reserved.