Phthalazines. XV. Ring transformation of phthalazines into naphthalenes by means of inverse-electron-demand Diels-Alder reaction.
作者:Etsuo OISHI、Naokata TAIDO、Ken-ichi IWAMOTO、Akira MIYASHITA、Takeo HIGASHINO
DOI:10.1248/cpb.38.3268
日期:——
The 1-substituted phthalazines 6 underwent inverse-electron-demand Diels-Alder reaction with the enamines 3 and ynamines 9, resulting in the formation of 1-substituted naphthalenes.Thus, 1-phthalazinecarbonitrile (6b) reacted with 3a-i to give the corresponding 1-naphthonitriles 7a-e, g, h and 2, 3-kihydro-1-naphthonitriles 8f, i, respectively. Similarly, reaction of 1-(methylsulfonyl)phthalazine (6c) with 3a, b, d, f gave the corresponding 1-(methylsulfonyl)naphthalenes 10a, b, d and 1-(methylsulfonyl)-2, 3-dihydronaphthalene 11f. Furthermore, 1-methylthio- (6e), 1-phenyl- (6f), 1-methyl-(6b), 1-chlorophthalazines (6h) and phthalazine (6a) reacted with 3a to afford the corresponding 4-substituted 2, 3-dihydro-1H-benz[f]indenes 12e-h, a, respectively.A similar ring transformation was found to proceed between 1, 4-phthalazinedicarbonitrile (14) and 1-methyl-1H-indole (13), giving the benzo[b]carbazoledicarbonitrile (15).Compounds 6b and 6c also underwent inverse-electron-demand Diels-Alder reaction with the ynamines 9a, b to give the corresponding 1-cyano-16a, b and 1-(methylsulfonyl)naphthalenes 17a, b, respectively.
因此,1-酞嗪甲腈(6b)与 3a-i 反应,分别得到相应的 1-萘甲腈 7a-e、g、h 和 2、3-基氢-1-萘甲腈 8f、i。同样,1-(甲磺酰基)酞嗪(6c)与 3a、b、d、f 反应,得到相应的 1-(甲磺酰基)萘 10a、b、d 和 1-(甲磺酰基)-2,3-二氢萘 11f。此外,1-甲硫基(6e)、1-苯基(6f)、1-甲基(6b)、1-氯酞嗪(6h)和酞嗪(6a)与 3a 反应,分别得到相应的 4-取代的 2,3-二氢-1H-苯并[f]茚 12e-h、a。化合物 6b 和 6c 还与亚萘胺 9a 和 b 发生了反电子需求的 Diels-Alder 反应,分别得到了相应的 1-氰基-16a、b 和 1-(甲磺酰基)萘 17a、b。