PHOTOCOLOURATION OF 2,4,4,6-TETRAARYL-1,4-DIHYDROPYRIDINES - A SEMIEMPIRICAL QUANTUM-CHEMICAL STUDY

Authors
BOHM S HOCEK M NESPUREK S KUTHAN J
Citation
S. Bohm et al., PHOTOCOLOURATION OF 2,4,4,6-TETRAARYL-1,4-DIHYDROPYRIDINES - A SEMIEMPIRICAL QUANTUM-CHEMICAL STUDY, Collection of Czechoslovak Chemical Communications, 59(2), 1994, pp. 262-272
Citations number
17
Categorie Soggetti
Chemistry
Journal title
Collection of Czechoslovak Chemical Communications → ACNP
ISSN journal
00100765
Volume
59
Issue
2
Year of publication
1994
Pages
262 - 272
Database
ISI
SICI code
0010-0765(1994)59:2<262:PO2-AS>2.0.ZU;2-6
Abstract
Molecular geometries of 1,4-dihydropyridines Ia, Ib and their possible photoisomers IIa - Va and IIb - Vb were optimized by the PM3 method. The electronic absorption spectra were calculated by the CNDO/S-CI pro cedure and compared with the experimental spectroscopic data. A probab le mechanism of the photocolouration of Ia, Ib, caused by sunlight or UV illumination, is proposed, and structures IIIa, IIIb are assigned t o violet or green coloured species.