¹³C NMR Spectroscopic Study of 2-[1-(trimethylsilyl)vinyl]-2-adamantyl Cation, the First ß-silyl-substituted Carbocation

Author

G. K. Surya Prakash
Prakash Reddy, Missouri University of Science and TechnologyFollow
Golam Rasul
Joseph Casanova
George Andrew Olah

Abstract

2-[1-(Trimethylsilyl)vinyl]-2-adamantyl cation (2) was prepared by the ionization of 2-[1-(trimethylsilyl)vinyl]-2-adamantanol in FSO₃H/SO₂CF at -130°C and was characterized by ¹³C NMR spectroscopy. For comparison, the 2-vinyl-2-adamantyl cation (4) was similarly prepared and characterized. The cationic center of 2 is deshielded by 11.5 ppm over that of 4, indicating no ß-silyl stabilization effect (either inductive or hyperconjugative). However, the low barrier for rotation across the C₂-C₁' bond in 2 indeed supports the intermediate perpendicular cation being stabilized by ß-silyl effect. The results are rationalized by MM2, ab initio, and IGLO calculations.

Recommended Citation

G. K. Prakash et al., "¹³C NMR Spectroscopic Study of 2-[1-(trimethylsilyl)vinyl]-2-adamantyl Cation, the First ß-silyl-substituted Carbocation," Journal of the American Chemical Society, vol. 114, no. 8, pp. 3076 - 3078, American Chemical Society (ACS), Apr 1992.

The definitive version is available at https://doi.org/10.1021/ja00034a047

Department(s)

Chemistry

International Standard Serial Number (ISSN)

0002-7863

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 1992 American Chemical Society (ACS), All rights reserved.

Publication Date

01 Apr 1992