UV-Illumination of (Z)-3-(2-phenylimidazo[1,2-a]pyridin-3-yl)-1,3-diphenylprop-2-en-1-one (1a) or its 6-methyl and 6-iodo derivatives 1c and 1g resulted in minor (E)-isomers 2a, 2c, and 2g and prevailing (E,Z)-mixtures of N-(pyridin-2-yl)-[(3,5-diphenylfuran-2-yl)phenylmethylidene]amines 3a, 3c, and 3g while only corresponding furanoic derivatives 3b and 3d-3f were obtained from 5-methyl (1b), 7-methyl (1d), 8-methyl (1e), and 5-phenyl (1f) derivatives of the (Z)-ketone 1a. VIS-Illumination of (Z)-1,3-diphenyl-3-(2-phenylimidazo[1,2-a]benzo[I]quinolin-3-yl)prop-2-en-1-one (4) led to N-(benzo[h]quinolin-2-yl)-[(3,5-diphenylfuran-2-yl)phenylmethylidene]amine (5). Photoisomers 2a, 2c, 2g, 3a-3g, and 5 were isolated and the molecular structure of 3c was X-ray determined. Mechanism of the photoisomerization is discussed using semiempirical quantum chemical calculations and compared with mass spectra of compounds 1a, 2a, 3a, 1g, 2g, and 3g.
对(
Z)-3-(
2-苯基咪唑[1,2-
a]
吡啶-3-基)-1,3-二苯基
丙烯酮(
1a)或其6-甲基和6-
碘衍
生物1c和
1g进行UV照射,会产生次要的(
E)-异构体
2a、
2c和
2g,以及主要的(
E,Z)-混合物
N-(
吡啶-2-基)-[(3,5-二苯基
呋喃-2-基)苯基甲烯]胺
3a、
3c和
3g,而只有相应的
呋喃衍
生物3b和
3d-3f从(
Z)-酮
1a的5-甲基(
1b)、7-甲基(
1d)、8-甲基(
1e)和5-苯基(
1f)衍
生物中获得。对(
Z)-1,3
-二苯基-3-(
2-苯基咪唑[1,2-
a]苯并[
I]
喹啉-3-基)
丙烯酮(
4)进行可见光照射,会产生
N-(苯并[
h]
喹啉-2-基)-[(3,5-二苯基
呋喃-2-基)苯基甲烯]胺
5。随后分离出光异构体
2a、
2c、
2g、
3a-3g和
5,并对
3c的分子结构进行了X射线测定。讨论了光异构化的机理,使用半经验量子
化学计算并与化合物
1a、
2a、
3a、
1g、
2g和
3g的质谱进行比较。