Photochemical Reaction of 2,3-Di[(E)-styryl]pyrazine Derivatives in the Crystalline State and in Solution
Autor: | Hitoshi Komiya, Yoichi Iitaka, Atsuo Takeuchi, Masaki Hasegawa, Takehiro Tsutsumi, Yukihiko Hashimoto, Kazuhiko Saigo |
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Rok vydání: | 1993 |
Předmět: | |
Zdroj: | Bulletin of the Chemical Society of Japan. 66:2987-2994 |
ISSN: | 1348-0634 0009-2673 |
Popis: | The photoreaction of 2,3-di[(E)-styryl]pyrazine derivatives was carried out in the crystalline state and in solution. Among them, 2,3-di(p-chlorostyryl)pyrazine and 2,3-di(p-cyanostyryl)pyrazine were photoreactive in the crystalline state and gave, upon photoirradiation, [2.2]orthocyclophanes in 76 and 58% yields, respectively. Such a topochemical photo-behavior was interpreted on the basis of X-ray crystallographic analyses of the crystals. The photoirradiation of 2,3-distyrylpyrazine in solution gave [2.2]orthocyclophane and anti head-to-tail type monocyclic dimer as the major products. The yields of the products varied depending on the solvent; with decreasing the polarity of the solvent, the yield of the cyclophane decreased, whereas the yield of the monocyclic dimer increased. In a similar manner, the photoirradiation of the other 2,3-distyrylpyrazine derivatives in acetonitrile/chloroform (10/1) or acetonitrile gave the corresponding [2.2]orthocyclophanes and monocyclic dimers, respectively, as majo... |
Databáze: | OpenAIRE |
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