Integration of Bromine and Cyanogen Bromide Generators for the Continuous-Flow Synthesis of Cyclic Guanidines
作者:Gabriel Glotz、René Lebl、Doris Dallinger、C. Oliver Kappe
DOI:10.1002/anie.201708533
日期:2017.10.23
A continuous‐flow process for the in situ on‐demand generation of cyanogen bromide (BrCN) from bromine and potassium cyanide that makes use of membrane‐separation technology is described. In order to circumvent the handling, storage, and transportation of elemental bromine, a continuous bromine generator using bromate–bromide synproportionation can optionally be attached upstream. Monitoring and quantification
描述了一种利用膜分离技术从溴和氰化钾原位按需生成溴化氰(BrCN)的连续流工艺。为了规避元素溴的处理,储存和运输,可以选择在上游连接使用溴酸盐-溴化物共比例的连续溴发生器。通过实施在线FTIR技术,可以监控和量化BrCN的产生。通过将Br 2和BrCN发生器串联连接,每分钟可产生0.2 mmol BrCN,这相当于0.8 m BrCN在二氯甲烷中的溶液。模块化Br 2/ BrCN生成器用于合成多种生物学相关的五元和六元环状am和胍。该设置既可以完全集成的连续格式进行操作,也可以在半分批模式下(对于反应性结晶有利)操作。