A comparative approach to the most sustainable protocol for the β-azidation of α,β-unsaturated ketones and acids
作者:John Andraos、Eleonora Ballerini、Luigi Vaccaro
DOI:10.1039/c4gc01282h
日期:——
In this contribution we have used green metrics analysis to compare the material efficiency, environmental impact, and safety-hazard impact in order to compare flow and batch procedures for azidation of α,β-unsaturated carbonyls.
We report herein a clean multistep flow process that starting from α,β-unsaturated ketones 1 allows the preparation of N-Boc-γ-amino alcohols 3 in high yields. The final products have been isolated in pure form without any additional purification step. The cleanness and environmental efficiency achieved using our protocol are proven by the calculation of green metrics such as E-factors.
herein report a multi-stepflow protocol for the synthesis of 1,4-disubstituted 1,2,3-triazoles starting from α,β-unsaturated carbonyls. Best results, both in terms of chemical productivity and sustainability, were obtained using a sequential combination of two flowreactors: one packed with a tailor-made POLITAG-F organocatalytic system and a copper tube apparatus. Moreover, the use of aqueous acetonitrile
我们在此报告了从 α,β-不饱和羰基开始合成 1,4-二取代 1,2,3-三唑的多步流程方案。使用两个流动反应器的顺序组合获得了化学生产率和可持续性方面的最佳结果:一个装有定制的POLITAG-F有机催化系统和铜管装置。此外,水性乙腈共沸物的使用在两个开发的过程中都产生了优异的催化性能,同时提供了一个废物最少的多步骤方案。实际上,叠氮化物中间体随后无需额外的纯化步骤即可反应,并且乙腈共沸物水溶液可以在该过程结束时大量回收/再利用。1,4-二取代的 β-酮基 1,2,3-三唑以高产率获得,这可能与低 E 因子值相关。最后,还给出了流程的绿色指标评估,以量化与使用我们的流程策略相关的优势。