Conjugated-triene intermediates in the Sommelet-Hauser rearrangement of cyclic 1-methyl-2-phenylammonium 1-methylides.
作者:Fumihiko SUMIYA、Naohiro SHIRAI、Yoshiro SATO
DOI:10.1248/cpb.39.36
日期:——
Fluoride ion-induced desilylation of 1-methyl-1-(trimethylsilyl)methyl-2-(2-substituted phenyl)pyrrolidinium (3a), -piperidinium (3b and 3c), and -perhydroazepinium iodides (3d and 3e) gave high yields of eight- (5a), nine- (5b and 5c), and ten-membered cyclic amines (5d, 5e, 6d and 6e), containing conjugated-triene bond systems. These triene products are intermediates in the Sommelt-Hauser rearrangement of cyclic 1-methyl-2-phenylammonium 1-methylides (4), and were isomerized to the corresponding Sommelet-Hauser rearrangement products (7) in the presence of a strong base or an acid (except for 5b). Heating of these trienes in xylene yielded mixtures of the Stevens rearrangement products (8) and ring-opened amines (9). Selective formation of 8 was achieved by ultraviolet irradiation of the trienes (5) in hexane. The reaction mechanisms are discussed.
氟离子诱导的 1-甲基-1-(三甲基硅烷基)甲基-2-(2-取代苯基)吡咯烷鎓(3a)、-哌啶鎓(3b 和 3c)和-全氢氮杂卓鎓碘化物(3d 和 3e)的脱硅反应和-全氢氮杂卓碘化物(3d 和 3e),高产率地得到了含有共轭三烯键系统的八元环胺(5a)、九元环胺(5b 和 5c)和十元环胺(5d、5e、6d 和 6e)。这些三烯产物是环状 1-甲基-2-苯基铵 1-甲基化物(4)的 Sommelt-Hauser 重排的中间产物,在强碱或强酸(5b 除外)的存在下,可异构化成相应的 Sommelet-Hauser 重排产物(7)。在二甲苯中加热这些三烯,可得到斯蒂文斯重排产物(8)和开环胺(9)的混合物。在己烷中用紫外线照射三烯(5),可以选择性地生成 8。本文对反应机理进行了讨论。