Journalartikel

Jahr der Veröffentlichung: 2010

Seiten: 6229-6235

Zeitschrift: The Journal of Organic Chemistry

Bandnummer: 75

Heftnummer: 18

ISSN: 0022-3263

DOI Link: https://doi.org/10.1021/jo101330p

Verlag: American Chemical Society

Abstract: 
Consecutive ring-expansion reactions of oxiranes with dimethylsulfxonium methylide were studied experimentally and modeled computationally at the density functional theory (DFT) and second-order Moller-Plesset (MP2) levels of theory utilizing a polarizable continuum model (PCM) to account for solvent effects. While the epoxide to oxetane ring expansion requires 13-17 kcal mol(-1) activation and occurs at elevated temperatures, the barriers for the ring expansions to oxolanes are higher (ca. 25 kcal mol(-1)) and require heating to 125 degrees C. Further expansions of these oxolanes to the six-membered oxanes are hampered by high barriers (ca. 40 kcal mol(-1)). We observe the complete conservation of the enantiomeric purities for the nucleophilic ring expansions of enantiomeric 2-mono- and 2,2-disubstituted epoxides and oxetanes with dimethylsulfoxonium methylide. This is a convenient general approach for the high-yielding preparation of optically active four- and five-membered cyclic ethers from oxiranes.

Harvard-Zitierstil: Butova, E., Barabash, A., Petrova, A., Kleiner, C., Schreiner, P. and Fokin, A. (2010) Stereospecific Consecutive Epoxide Ring Expansion with Dimethylsulfoxonium Methylide, The Journal of Organic Chemistry, 75(18), pp. 6229-6235. https://doi.org/10.1021/jo101330p

APA-Zitierstil: Butova, E., Barabash, A., Petrova, A., Kleiner, C., Schreiner, P., & Fokin, A. (2010). Stereospecific Consecutive Epoxide Ring Expansion with Dimethylsulfoxonium Methylide. The Journal of Organic Chemistry. 75(18), 6229-6235. https://doi.org/10.1021/jo101330p