NOVEL REACTIONS OF AMINOOXOSULFONIUM YLIDE WITH EPOXIDES
作者:Kentaro Okuma、Kenshin Nishimura、Hiroshi Ohta
DOI:10.1246/cl.1984.93
日期:1984.1.5
Reactions of (dimethylamino)phenyloxosulfonium methylide with epoxides were carried out. When aromatic epoxides were used as substrates, cyclopropyl sulfones and oxetanes were obtained. When aliphatic epoxides were used, the products were only the cyclopropyl sulfones. While the aminooxosulfonium ylide acts as a methylene transfer reagent to give the corresponding oxetanes, an intramolecular SN2 type
Compounds are provided according to Formula (I): and pharmaceutically acceptable salts thereof, and pharmaceutical compositions thereof; wherein R2, R3, R4, R5, and and R6 are as defined herein. Compounds of the present invention are contemplated useful for the prevention and treatment of a variety of conditions.
Ng, John S., Synthetic Communications, 1990, vol. 20, # 8, p. 1193 - 1202
作者:Ng, John S.
DOI:——
日期:——
Stereoselectivity and Substrate Specificity in the Kinetic Resolution of Methyl-Substituted 1-Oxaspiro[2.5]octanes by <i>Rhodotorula </i><i>g</i><i>lutinis</i> Epoxide Hydrolase
作者:Carel A. G. M. Weijers、Petra Meeuwse、Robert L. J. M. Herpers、Maurice C. R. Franssen、Ernst J. R. Sudhölter
DOI:10.1021/jo050533w
日期:2005.8.1
[GRAPHICS]The kinetic resolution of a range of methyl-substituted 1-oxaspiro[2.5]octanes by yeast epoxide hydrolase (YEH) from Rhodotorula glutinis has been investigated. The structural determinants of substrate specificity and stereoselectivity of YEH toward these substrates appeared to be the configuration of the epoxide ring and the substitution pattern of the cyclohexane ring. For all compounds tested, O-axial epoxides were hydrolyzed faster than the corresponding O-equatorial compounds. In concern of the ring substituents,.YEH preferred methyl groups on the Re side of the ring. Placement of substituents close to the spiroepoxide carbon decreased the reaction rate but increased enantioselectivity. YEH-catalyzed kinetic resolutions of 4-methyl 1-oxaspiro [2.5] octane epimers were most enantioselective,(E > 100).
Revisiting the Corey–Chaykovsky reaction: the solvent effect and the formation of β-hydroxy methylthioethers
作者:Yu Peng、Jin-Hui Yang、Wei-Dong Z. Li
DOI:10.1016/j.tet.2005.10.068
日期:2006.2
The classical Corey-Chaykovsky (CC) reaction of ketones in ethereal solvents (i.e., THF or Et2O) resulted in the production of a 14 significant amount of P-hydroxy methylthioether 2 along with normal epoxide product 1. Some interesting and synthetically useful transformations of the CC reaction product of cyclopropyl ketones were also described. (c) 2005 Elsevier Ltd. All rights reserved.