Angular dependence of the vicinal interproton spin–spin coupling in silacyclohexanes. The conformational energy term of the methyl group in 1-methyl-1-silacyclohexane

✍ Scribed by Robert Carleer; Marc J. O. Anteunis

• Publisher: John Wiley and Sons
• Year: 1979
• Tongue: English
• Weight: 449 KB
• Volume: 12
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1270121205

✦ Synopsis

Abstract

An approximate Karplus‐Conroy relationship between the vicinal coupling constants J(HSiCH) in a silaethane fragment and the corresponding torsional angles τ in silacyclohexanes is proposed. The relationship ^3^J(HSiCH) VS τ is asymmetric. The ^1^H NMR parameters and conformational features of cis‐ and trans‐3,5‐dimethyl‐1‐silacyclonexane and 3‐silabicyclo[3.2.1]octane are discussed, and the conformational energy term for the methyl group in 1‐methyl‐1‐silacyclohexane is found to be approximately 1.45 kJ mole^−1^ in favour of the axial position for the methyl group, in good agreement with previously calculated values.