Unprecedented cooperative DBU-CuCl2 catalysis for the incorporation of carbon dioxide into homopropargylic amines leading to 6-methylene-1,3-oxazin-2-ones
作者:Raffaella Mancuso、Ida Ziccarelli、Christian S. Pomelli、Corrado Cuocci、Nicola Della Ca'、Diego Olivieri、Carla Carfagna、Bartolo Gabriele
DOI:10.1016/j.jcat.2020.03.033
日期:2020.7
catalysis by DBU and CuCl2, which allows the carboxylation of homopropargylic amines to high value added 6-methylene-1,3-oxazin-2-ones. This reaction also represents the first efficient method for the catalytic incorporation of CO2 into an acyclic substrate to give oxazinones. DFT calculations are in agreement with a mechanism involving: a) deprotonation of the substrate by DBU; b) CO2 capture with
Intermolecular reacitons of N-alkoxycarbonyliminium ions with propargyltrimethylsilane; oxazinone versus allene formation
作者:Peter M. Esch、Henk Hiemstra、W. Nico Speckamp
DOI:10.1016/0040-4020(92)85018-a
日期:1992.1
Intermolecular reactions of N-alkoxycarbonyliminium ions with propargyltrimethylsilane mainly lead to 6-(trimethylsilyl)methyl-3,4-dihydro-2H-1,3-oxazinones, formed by intramolecular trapping of a stabilized β-silyl vinylic cation. α-Allenyl carbamates are obtained as minor products. The oxazinone/allene ratio is dependent on the nature of the Lewis acid and the solvent used.