The photochemistry of the title compound 1 in methanol and 2,2,2-trifluoroethanol has been examined. In both solvents two ether products were obtained: one (18) resulting from trapping of the carbocation 2 (expected from photosolvolysis of 1), and the other (19) from the carbocation 3 (expected after rearrangement by hydride migration of cation 2). The substituted trans- and cis-stilbene derivatives 20 and 21 were also primary photoproducts. Analysis of product yields as a function of time revealed that the ether product 19 was formed by secondary photolysis of the stilbene derivatives, presumably by a pathway involving excited state protonation. Nanosecond laser flash photolysis results demonstrated that substituted trans-stilbene 20 was produced on the same time scale as the laser pulse.Key words: ester photochemistry, stilbene photoadditions, carbocation rearrangements.
标题化合物1在甲醇和2,2,2-三氟乙醇中的光化学性质已经被研究。在两种溶剂中,都得到了两种醚产物:一种(18)是由于捕获了碳阳离子2(从1的光溶解预期而来),另一种(19)是由于碳阳离子3(在阳离子2的氢迁移重排后预期而来)而产生的。取代的反-和顺-苯乙烯衍生物20和21也是主要的光产物。随着时间的推移,对产物产率的分析表明,醚产物19是通过反式-苯乙烯衍生物的二次光解产生的,可能是通过涉及激发态质子化的途径。纳秒激光脉冲光解实验结果表明,取代的反式-苯乙烯20在与激光脉冲相同的时间尺度上产生。关键词:酯光化学,苯乙烯光加成,碳阳离子重排。