One-pot synthesis of α-bromo- and α-azidoketones from olefins by catalytic oxidation with in situ-generated modified IBX as the key reaction
作者:Ajeet Chandra、Keshaba Nanda Parida、Jarugu Narasimha Moorthy
DOI:10.1016/j.tet.2017.08.019
日期:2017.10
α-azidoketones starting from olefins have been developed by employing catalytic oxidation of the intermediary bromohydrins with in situ-generated modified IBX as the key reaction. The improved procedure involves initial formation of bromohydrin by the reaction of olefin with NBS in acetonitrile-water mixture (1:1) at rt followed by oxidation with in situ-generated 3,4,5,6-tetramethyl-2-iodoxybenzoic acid (TetMe-IBX)
通过将中间溴代醇催化氧化与原位生成的修饰IBX作为关键反应,已经开发出了简单的一锅法,用于从烯烃开始合成α-溴代酮和α-叠氮酮。改进的方法包括通过在室温下使烯烃与NBS在乙腈-水混合物(1:1)中反应,然后再用原位生成的3,4,5,6-四甲基-2-碘氧基苯甲酸((TetMe-IBX),以催化量由3,4,5,6-四甲基-2-碘苯甲酸和Oxone制得。使用NaN 3 / NaHCO 3在同一个锅中将α-溴酮进一步转化为相应的α-叠氮酮。一锅转换对于包括环以及无环脂族烯烃以及富电子和缺电子的苯乙烯在内的多种烯烃是通用的。对于同时含有富电子和不足双键的底物,已证明了富电子双键的化学选择性溴羟基化和随后的氧化成α-溴代酮。