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Restricted internal rotation of a t-butyl group bonded to an aromatic ring

✍ Scribed by Gaku Yamamoto; Michinori Ōki

Publisher
Elsevier Science
Year
1986
Tongue
French
Weight
146 KB
Volume
27
Category
Article
ISSN
0040-4039

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✦ Synopsis

Low temperature lH NMR study of 1,3-di-t-butyl-9-(3,5_dimethylphenoxy)triptycene revealed restricted rotation of the I-t-butyl group with an energy barrier of 9.2 kcal mol-1, which is the highest ever reported for internal rotation of an aromatic t-butyl group. In contrast with the abundant examples of restricted rotation of a primary or a secondary alkyl group attached to an sp2-hybridized atom, dynamic NMR studies on the counterparts with a

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