The B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>Boron Lewis Acid Route to Arene-Annulated Pentalenes
作者:Chao Chen、Marcel Harhausen、Aiko Fukazawa、Shigehiro Yamaguchi、Roland Fröhlich、Constantin G. Daniliuc、Jeffrey L. Petersen、Gerald Kehr、Gerhard Erker
DOI:10.1002/asia.201400096
日期:2014.6
(24, 8) with the frustrated Lewis pair B(C6F5)3/P(o‐tolyl)3. The overall formation of the C6F5‐substituted products formally require HB(C6F5)2 cleavage in an intermediate dehydroboration step. This was confirmed in the reaction of a thienylethynyl‐containing starting material 21 with B(C6F5)3, which gave the respective annulated pentalene product 23 that had the HB(C6F5)2 moiety 1,4‐added to its thiophene
4,5-二甲基1,2-双(1-萘乙炔基)苯(12)经过强硼路易斯酸B(C 6 F 5)3处理后迅速发生多环闭合反应,得到多环环化的,平面共轭π系统13(50%产率)。在该反应过程中,C 6 F 5基团从硼转移到碳上。类似地,用CH 3 B(C 6 F 5)2处理12,得到13(C 6 F 5-转移)和产物15的混合物。,它是由CH 3基团转移形成的。1,2-双(苯基乙炔基)苯(8)用CH同样反应3 B(C 6 ˚F 5)2,得到各个C的混合物6 ˚F 5 -和CH 3个取代dibenzopentalenes 10和16。该反应被认为是通过具有乙烯基阳离子反应性的两性离子中间体进行的。一些B(C 6 ˚F 5)3 -取代的物质(26,27)因此通过原位去质子化处理后的各1,2-双(炔基)苯原料(构成24,8)与沮丧路易斯对B(C 6 ˚F 5)3 / P(ø -甲苯基)3。C 6 F 5取代