Journalartikel

Jahr der Veröffentlichung: 2006

Seiten: 4813-4818

Zeitschrift: European Journal of Organic Chemistry

Bandnummer: 2006

Heftnummer: 21

ISSN: 1434-193X

DOI Link: https://doi.org/10.1002/ejoc.200600485

Verlag: Wiley

Abstract: 
Dimethoxycarbene was prepared from an oxadiazoline precursor under high-vacuum flash pyrolysis (HVFP) conditions and was trapped at low temperatures by matrix isolation techniques (Ar, 10 K). The excellent agreement between the computed [CCSD(T)/cc-pVDZ] IR spectrum of the mixture of conformers of dimethoxycarbene and the experimentally measured IR absorptions allows a detailed analysis of the conformational preference of dimethoxycarbene. Its UV spectrum is in agreement with earlier studies and our TD-B3LYP/6-311+G(d,p) computations. The computed [CCSD(T)/cc-pVDZ] rotational profile is rather steep and separates the s-trans,s-trans and s-cis,s-trans conformers by a 16 k cal mol(-1) barrier, whilst the s-cis,s-cis conformer is too high-lying to be observable (+17 k cal mol 1). In marked contrast with the gauche,guuche minimum of dimethoxymethane, the s-trans,s-trans conformer of dimethoxycarbene is slightly preferred (0.5 k cal mol(-1)). The s-cis,s-trans conformer equilibrates at the high temperatures required during HFVP generation and both conformers can be identified in the IR spectrum of the argon matrix at 10 K. The conformational preference is partly due to the minimization of the overall dipole moment in the s-trans,s-trans conformer.

Harvard-Zitierstil: Reisenauer, H., Romanski, J., Mloston, G. and Schreiner, P. (2006) Dimethoxycarbene: Conformational analysis of a reactive intermediate, European Journal of Organic Chemistry, 2006(21), pp. 4813-4818. https://doi.org/10.1002/ejoc.200600485

APA-Zitierstil: Reisenauer, H., Romanski, J., Mloston, G., & Schreiner, P. (2006). Dimethoxycarbene: Conformational analysis of a reactive intermediate. European Journal of Organic Chemistry. 2006(21), 4813-4818. https://doi.org/10.1002/ejoc.200600485