A sustainable approach for the catalytic synthesis of unsymmetricalureas from disilylamines through catalytic activation of carbon dioxide as a C1 building block under ambient pressure was performed by using a commercially available easy-to-handle NH4VO3. This catalytic system displayed a wide range of substrate applicability without the use of any dehydrating reagents or bases. Gram-scale catalytic
通过使用市售的易于处理的 NH 4 VO 3,在环境压力下催化活化二氧化碳作为 C1 结构单元,从二甲硅烷胺催化合成不对称脲的可持续方法。该催化体系在不使用任何脱水试剂或碱的情况下表现出广泛的底物适用性。成功进行了克级催化反应,以验证在环境二氧化碳压力下催化合成不对称尿素的可扩展性。
Carbonyldiimidazole-Mediated Lossen Rearrangement
作者:Pascal Dubé、Noah F. Fine Nathel、Michael Vetelino、Michel Couturier、Claude Larrivée Aboussafy、Simon Pichette、Matthew L. Jorgensen、Mark Hardink
DOI:10.1021/ol9023387
日期:2009.12.17
mediate the Lossenrearrangement of various hydroxamic acids to isocyanates. This process is experimentally simple and mild, with imidazole and CO2 being the sole stoichiometric byproduct. Significant for large-scale application, the method avoids the use of hazardous reagents and thus represents a green alternative to standard processing conditions for the Curtius and Hofmann rearrangements.