Contribution of Hyperconjugation and Inductive Effects to the Pseudo -anomeric Effect in 4-Substituted Methoxycyclohexanes.

Autor: Piscelli BA; Chemistry Institute, University of Campinas, Monteiro Lobato Street, Campinas 13083-862, Sao Paulo, Brazil., O'Hagan D; School of Chemistry, University of St Andrews, North Haugh, St Andrews KY16 9ST, Fife, U.K., Cormanich RA; Chemistry Institute, University of Campinas, Monteiro Lobato Street, Campinas 13083-862, Sao Paulo, Brazil.
Jazyk: angličtina
Zdroj: The journal of physical chemistry. A [J Phys Chem A] 2023 Jan 26; Vol. 127 (3), pp. 724-728. Date of Electronic Publication: 2023 Jan 17.
DOI: 10.1021/acs.jpca.2c08090
Abstrakt: The importance of electrostatic nonconventional hydrogen bonds (NCHBs) to the pseudo -anomeric effect of 4-substituted methoxycyclohexanes is evaluated using theory [natural bond orbital (NBO)] to deconvolute electrostatic from other contributing effects. There is an interesting interplay between σ CH → σ CX * hyperconjugation and the electropositive charge on 3,5-axial hydrogens (H ax ). In essence, better σ CX * (or π CO * ) acceptors increase the charge on 3,5-CH ax , which in turn strengthens C δ+ H ax ··· δ- OMe NCHB interactions.
Databáze: MEDLINE
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