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Restricted rotation in sterically hindered dichalcogenides. A dynamic NMR study

✍ Scribed by B. Mario Pinto; Ronald Y. N. Leung; R. Dev Sharma

Publisher
John Wiley and Sons
Year
1988
Tongue
English
Weight
573 KB
Volume
26
Category
Article
ISSN
0749-1581

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✦ Synopsis

The rotational barriers in bis(2,4,Ctri-tert-butylphenyl) diselenide and ditelluride have been investigated by total line-shape analysis of variabletemperature 'H NMR spectra in CFCI,-CD,CI, (85: 15). The free energies of activation, AGf,,, K, for the diselenide and ditelluride were determined to be 49.4 & 0.6 and 39.2 f 0.2 kJ mol-', respectively. The difference is attributed to the dominance of steric effects in the transition state for rotation.

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