Reaction of the bridged [14]annulenequinone, trans-10b,10c-dimethyl-10b,10c-dihydropyrene-2,7-quinone (12), with malononitrile in the presence of pyridine and TiCl4 gave 68% of the deep-purple extended TCNQ derivative, α,α,α′,α′-tetracyano-trans-10b, 10c-dimethyl-10b, 10c-dihydropyrene-2,7-quinodimethide (13). In solution, quinodimethide 13 appears to form a complex with diethylamine, but is too weak an electron acceptor to form complexes with tetrathiafulvalene, TTF, and related donors. The reduction potential of 13 was substantially lower than that found for TCNQ itself, and in properties 13 behaves more like a benzannelated TCNQ derivative, e.g., α,α,α′,α′-tetracyanopentacene-7,14-quinodimethide (11), than a pyrene derivative, e.g., α,α,α′,α′-tetracyanopyrene-2,7-quinodimethide (6). This is in agreement with molecular orbital calculations, which indicate that the LUMOs of 13 and 11 are approximately 0.6 eV higher in energy than those for 6 and TCNQ. Keywords: TCNQ — extended, TCNQ-pyrene derivative, reduction potential, annulene-quinodimethide, electron acceptor — weak.
在
吡啶和TiCl4的存在下,桥接[14]
环戊二烯醌,trans-10b,10c-二
甲基-10b,10c-
二氢吡啶-2,7-醌(12)与
丙二腈反应,得到深紫色的扩展TCNQ衍
生物,α,α,α′,α′-四
氰基-trans-10b,10c-二
甲基-10b,10c-
二氢吡啶-2,7-
喹啉二
甲酸二
酰亚胺(13),产率为68%。在溶液中,
喹啉二
甲酸二
酰亚胺13似乎形成了与
二乙胺的复合物,但它是一个太弱的电子受体,无法与
四硫富瓦烯,
TTF和相关供体形成复合物。与TCNQ本身相比,13的还原电位显着较低,并且在性质上,13的行为更像是
苯并环TCNQ衍
生物,例如α,α,α′,α′-四
氰基五环七十四
喹啉二
甲酸二
酰亚胺(11),而不是
吡啶衍生物,例如α,α,α′,α′-四
氰基
芘-2,7-
喹啉二
甲酸二
酰亚胺(6)。这与分子轨道计算一致,表明13和11的LU
MO能级比6和TCNQ高约0.6 eV。关键词:TCNQ-扩展,TCNQ-
吡啶衍生物,还原电位,
环戊二烯-
喹啉二
甲酸二
酰亚胺,电子受体-弱。