title: Conformational study of 2-arylazo-1-vinylpyrroles.
abstract: Conformational study of 2-phenylazo-1-vinylpyrrole and 2-(4-bromophenyl)azo-5-methyl-1-vinylpyrrole was performed on the basis of the experimental measurements and high-level ab initio calculations of their 13C--13C and 13C--1H spin-spin coupling constants, showing marked stereochemical behaviour upon the internal rotation of the vinyl group and the pyrrolyl moiety. In liquid phase, both compounds were found to adopt predominant s-trans-s-trans conformation with the noticeable population (ca. 30%) of the higher-energy s-cis-s-trans conformation in the latter compound. As follows from the X-ray data, 2-phenylazo-1-vinylpyrrole crystallizes in s-trans-s-trans conformation while the crystalline molecular structure of 2-(4-bromophenyl)azo-5-methyl-1-vinylpyrrole is s-cis-s-trans.
authors.affiliation: A. E. Favorsky Institute of Chemistry, Irkutsk, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russia.
authors.forename: Yury Yu
authors.initials: YY
authors.lastname: Rusakov
authors.forename: Leonid B
authors.initials: LB
authors.lastname: Krivdin
authors.forename: Elena Yu
authors.initials: EY
authors.lastname: Senotrusova
authors.forename: Elena Yu
authors.initials: EY
authors.lastname: Schmidt
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Vasiltsov
authors.forename: Albina I
authors.initials: AI
authors.lastname: Mikhaleva
authors.forename: Boris A
authors.initials: BA
authors.lastname: Trofimov
authors.forename: Oleg A
authors.initials: OA
authors.lastname: Dyachenko
authors.forename: Anatolii N
authors.initials: AN
authors.lastname: Chekhlov
authors.forename: Olga N
authors.initials: ON
authors.lastname: Kazheva