Restricted rotation involving the tetrahedral carbon. LXIV. Barriers to rotation of s-alkyl groups in 9-s-alkyl-8,13-difluoro-1,4-dimethyl- and 1,2,3,4-tetrachloro-triptycenes

Authors
Oki, M Nishino, M Kaieda, K Nakashima, T Toyota, S
Citation
M. Oki et al., Restricted rotation involving the tetrahedral carbon. LXIV. Barriers to rotation of s-alkyl groups in 9-s-alkyl-8,13-difluoro-1,4-dimethyl- and 1,2,3,4-tetrachloro-triptycenes, B CHEM S J, 74(2), 2001, pp. 357-361
Citations number
21
Categorie Soggetti
Chemistry
Journal title
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
ISSN journal
00092673 → ACNP
Volume
74
Issue
2
Year of publication
2001
Pages
357 - 361
Database
ISI
SICI code
0009-2673(200102)74:2<357:RRITTC>2.0.ZU;2-V
Abstract
9-(3-Acetoxy-1-methylpropyl)-8,13-difluoro-1,4-dimethyltriptycene and 9-(1- methyl-2-propenyl)-8,13-difluoro-1,4-dimethyl- and 1,2,3,4-tetrachloro-trip tycenes were prepared. Their barriers to internal rotation around the C(9)- C(alkyl) bonds were measured by the classical kinetics. The barrier was aff ected a little by the substituent, being ca. 25-26 kcal mol(-1). Rotamer di stributions in these compounds and possible causes for these indifferent ba rriers to rotation are discussed.