作者:James W. Pavlik、Naod Kebede
DOI:10.1021/jo970897r
日期:1997.11.1
confirming the generality of this pathway in pyrazole photochemistry. Direct irradiation of 1-methyl-5-phenylpyrazole (3) resulted in the formation of 1-methyl-5-phenylimidazole (7), 1-methyl-2-phenylimidazole (8), and 1-methyl-4-phenylimidazole (4). Deuterium labeling revealed that these products were formed by P(4), P(6), and P(7) permutation pathways, respectively. (E)/(Z)-3-(N-methylamino)-3-phenylpropenenitrile
1-甲基-4-苯基吡唑(2)在甲醇中的直接辐照导致区域特异性光变位成1-甲基-4-苯基咪唑(4)并光解为(E)/(Z)-3-(N-甲基氨基)- 2-苯基丙烯腈(5)和(E)/(Z)-2-(N-甲基氨基)-1-苯基乙烯基异氰酸酯(6)。氘标记确认通过P(4)排列途径发生的光移位。单独的实验表明5和6经历(Z)->(E)异构化和光环化成咪唑4。这些反应的量子产率表明,序列2-> 6-> 4是P( 4)2-> 4的光子转移。也检测到异氰酸酯作为各种其他吡唑的P(4)光子转移的中间体,证实了该途径在吡唑光化学中的普遍性。1-甲基-5-苯基吡唑(3)的直接照射导致形成1-甲基-5-苯基咪唑(7),1-甲基-2-苯基咪唑(8)和1-甲基-4-苯基咪唑(4 )。氘标记表明,这些产物分别由P(4),P(6)和P(7)排列途径形成。(E)/(Z)-3-(N-甲基氨基)-3-苯基丙烯腈(9)和(E)/(Z)-