determination of the very high barriers to conformational processes by the neat racemization technique. part 1: barriers to ring inversion in dibenzo [a,c] dinaphtho [2,3-e; 2,3-g] cyclooctatetraene and hindered rotation in 2,2'-dimethyl binaphthyl

نویسندگان

parviz rashidi ranjbar

jan sandström

george w. schriver

henry n.c. wong

چکیده

a method is described by which it is possible to determine the high barrier to ring inversion and hindered rotation by neat racemization of optically active compounds when the racemization is caused by ring inversion or hindered rotation. the method is based preparation of sufficiently pure enantiomers, mainly by chromatography on swollen microcrystalline triacetylcellulose (tac). by this technique the barrier to ring inversion in dibenzo [a,c] dinaphtho [2,3-e; 2,3-g] cyclooctatetraene, a tetrabenzocyclooctatetraene analogue, was determined to be 67.2±0.8 kcl/mol, a record as the highest conformational barrier ever reported. the barrier to hindered rotation in 2,2'-dimethyl binaphthyl was determined by this method to be 49.5±0.5 kcl/mol.

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Determination of the Very High Barriers to Conformational Processes by the Neat Racemization Technique. Part 1: Barriers to Ring Inversion in Dibenzo [a,c] Dinaphtho [2,3-e; 2,3-g] Cyclooctatetraene and Hindered Rotation in 2,2'-Dimethyl Binaphthyl

A method is described by which it is possible to determine the high barrier to ring inversion and hindered rotation by neat racemization of optically active compounds when the racemization is caused by ring inversion or hindered rotation. The method is based preparation of sufficiently pure enantiomers, mainly by chromatography on swollen microcrystalline triacetylcellulose (TAC). By this t...

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عنوان ژورنال:
iranian journal of chemistry and chemical engineering (ijcce)

ناشر: iranian institute of research and development in chemical industries (irdci)-acecr

ISSN 1021-9986

دوره 15

شماره 1 1996

میزبانی شده توسط پلتفرم ابری doprax.com

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