Ab initio study of hyperconjugation effects on charge distribution in representative polycyclic alcohols

✍ Scribed by C.A. Taft; Peter Rudolf Seidl; J.Glauco R. Tostes; S.K. Lie; J.W. de M. Carneiro; W.A. Lester Jr.

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 470 KB
• Volume: 248
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(95)01319-9

✦ Synopsis

Ab initio calculations using fully optimized geometries are used to generalize hyperconjugation effects in a representative series of eight polycyclic alcohols. The systems studied include tetra-, penta-and hexa-cyclic structures with varying degrees of tension, due to compression and stretching of carbon-carbon and carbon-hydrogen bonds, and of distortion from normal bond angles as well to differences in van der Waals interactions. These findings indicate, in general, that carbon and hydrogen atoms with the proper spatial alignment relative to a nonbonding oxygen lone pair follow the same general trends as small acyclic alcohols. Results from minimum STO-3G basis-set calculations and the hyperconjugation model can generally distinguish clearly the subtleties of charge and bond length distributions observed in the various conformations of all the polycyclic alcohols investigated.