Novel tocopheryl compounds XXIV. Studies into the nitrosation chemistry of γ-tocopherol: preparation of 5-nitroso-γ-tocopherol via an organomercury derivative of vitamin E
作者:Anjan Patel、Falk Liebner、Kurt Mereiter、Thomas Netscher、Thomas Rosenau
DOI:10.1016/j.tet.2007.02.120
日期:2007.5
exists in equilibrium with its ortho-quinone monoxime tautomer 6, the latter being the major component with >99%. NMR and analytical data of the tautomeric couple are reported for the first time. The chemistry of the nitrosation of γ-tocopherol was studied in detail. In the presence of oxygen, 5 is readily oxidized to 5-nitro-γ-tocopherol (7), whereas at elevated temperatures an additional process, the
通过直接亚硝化γ-生育酚(3)不能获得5-亚硝基-γ-生育酚(5),但是在非质子条件下第一次通过有机汞中间体(11)的亚硝化合成了5-亚硝基-γ-生育酚。在质子条件下5与其邻-醌单肟互变异构体6平衡存在,后者是> 99%的主要成分。首次报道了互变异构体对的NMR和分析数据。详细研究了γ-生育酚的亚硝化化学。在有氧的情况下,5容易被氧化为5-硝基-γ-生育酚(7),而在高温下是一个额外的过程,在失去羟胺的情况下,单肟6转化为5,6-生育酚二酮(8)。实验结果与DFT计算的结果相符。