臺灣博碩士論文加值系統

　　2-(4-甲氧基-)反-苯乙烯基口塞吩(1)在有碘存在的條件下經紫外光照射後，與二苯乙烯(stibene)進行類似的反應，能得到環化氧化產物6-甲氧基-奈并(3,4,b)口塞吩(1c)。但在無氧化劑存在的條件下照光，卻能得到重組的產物4-(5'-苯并口塞吩基-）反-３-丁烯-２-酮(1a)。我們推測此反應的進行先須經由二氫口塞吩的共振分子中間體(18)，再經過質子轉移後開環脫去亞甲基而產生化合物(1a)。類似的反應也發生在3-(4'-甲氧基-)反-苯乙烯基口塞吩(2)、2或3-(4'甲氧基-)反-苯乙烯基口夫喃(3)或(4)以及2-(4'-甲氧基-)反-苯乙烯基-N-甲基口比咯(5)的照光反應，分別可得到4-(6'-苯并口塞吩基-)反-3-丁烯-2-酮(2a）、4-(5'-苯并口夫喃基-)反-3-丁烯-2-酮(3a)、4-(6`-苯并口夫喃基-)反-3-丁烯-2-(4a)以及4-(N`-甲基-6`-苯并口比咯基-)反-3-丁烯-2-酮(5a)。但是，類似的反應卻不發生在2-(4`-甲氧基-)反-苯乙烯基-3-甲基口塞吩(6)的照光反應中，我們相信反應不進行的原因是因為甲基的轉移比質子的轉移還要困難，因此造成其進行其它的反應途徑，而產生2-(4'-羥基-)反-苯乙烯基口塞吩(6a)以及微量的4-(5'-2'-甲基苯並口塞吩基-)反-3-丁烯-2-酮(6b)。

　　In the presence of iodine, 2-(4'-methoxy- )trans- styrylthiophene (1) reacted and produced 6-methoxynaphtho(3,4,b) thiophene(1c) under the ultraviolet radiation; the similar reaction as stilbene reacted under the ultraviolet radiation. If there was no any oxidative reagent in the solution, we got 4-(5'-benzothiophenyl-)trans. -3-buten-2-one(la) which rearranged from compound (1). We thought that the conjugated intermediate of dihydronaphthothiophene(18) was produced and than a proton shifted、opened the ring、left a carbene, and got compound (1a). The same reactions happened when 3-(4'-methoxy-)-trans-styryl- thiophene(2)、2 or 3-(4'-methoxy-)-trans-styrylfuran(3 or 4)、2-(4'-methoxy)trans-styryl-N- methylpyrrole(5) were radiated by ulraviolet radiation, and we would get 4-(6'-benzothiophenyl-)rans-3-buted-2-one (2a)、4-(5'-benzofuryl-)-trans-3- buten-2-one (3a)、4-(6'-benzofuryl-) trans-3-buten-2-one(4a) and 4-(N'-methyl-5'-benzopyrrolyl-)trans-3-buten- 2-one(5a). It was interesting that 2-(4'-methoxy-)-trans-styryl-3-methyl thiophene(6) did not react the same photoreaction. We thought that the methyl-shift was diffcult than the proton-shift, so it would go to the different reaction pathway and produce 2-(4'-hydroxy-)trans-styrylthiophene(6a) and traced amount of 4-5'-2'- methylbenzothiophenyl-) trans-3- buten-2- one(6b).