LIQUID CRYSTALLINE SOLVENTS AS MECHANISTIC PROBES - 7. INVESTIGATION OF A PHOTOCHROMIC MEROCYANINE TO INDOLINOSPIROPYRAN ISOMERIZATION IN THE ISOTROPIC AND SMECTIC PHASES OF N-BUTYL STEARATE AND IN POLYBUTADIENE OLIGOMERS.

Article abstract of DOI:10.1080/00268948208071029

The unimolecular isomerization of a merocyanine (t - 2a) to an indolinospiropyran, 1 prime , 3 prime , 3 prime -trimethyl-6-nitrospiro left bracket 2H-benzopyran-2,2 prime -indoline right bracket (1a), has been followed in the isotropic and smectic liquid crystalline phases of n-butyl stearate (BS) and in three polybutadiene oligomers (PB). The rate constants, k// minus //t, for isomerization in PB demonstrate that viscosity is not a factor as long as the solvent chains are mobile. The k// minus //t for all three PB fractions ( eta 13. 1-506 cP) at 25 degree C range only from 1. 0 - 3. 6 min** minus **1. Comparison of the activation parameters in the two phases of BS with each other and with other solvents reveals that polarity considerations, although important, are incapable of explaining the data completely. The effect of solvent order on the activation parameters must be included.

Full text of DOI:10.1080/00268948208071029

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Molecular Crystals and Liquid
Crystals
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Liquid Crystalline Solvents
as Mechanistic Probes.
VII. Investigation of a
Photochromic Merocyanine
to Indolinospiropyran
Isomerization in the Isotropic
and Smectic Phases of n-Butyl
Stearate and in Polybutadiene
Oligomers
a
a
Joseph P. Otruba III & Richard G. Weiss
a
Department of Chemistry , Georgetown
University , Washington , D.C. , 20057
Published online: 14 Oct 2011.
To cite this article: Joseph P. Otruba III & Richard G. Weiss (1982) Liquid Crystalline
Solvents as Mechanistic Probes. VII. Investigation of a Photochromic Merocyanine
to Indolinospiropyran Isomerization in the Isotropic and Smectic Phases of n-Butyl
Stearate and in Polybutadiene Oligomers, Molecular Crystals and Liquid Crystals, 80:1,
165-178, DOI: 10.1080/00268948208071029
To link to this article: http://dx.doi.org/10.1080/00268948208071029
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