Transformation thermique de phenyl-2methyl-4 (methyl-1' diphenyl-2',3' cyclopropene-1' yl)-4 oxazoline-2 one-5 en un melange de dimethyl-2,3, -2,4, et -2,5,三苯基吡啶。Mecanisme faisant intervenir 丁腈橡胶中间体
Alkylation via tris(dialkylamino)sulfonium enolates
作者:R. Noyori、I. Nishida、J. Sakata
DOI:10.1016/s0040-4039(00)71493-6
日期:1980.1
Tris(dialkylamino)sulfoniumenolates generated from tris(diethylamino)sulfonium difluorotrimethylsiliconate and enol silyl ethers are readily alkylated by various alkyl halides under mild conditions.
A new, practical route to enoxysilanes is described from simple enolizable aldehydes or ketones, using the trimethylchlorosilane-sodium iodide—tertiary amine reagent in acetonitrile. From certain aldehydes, an onium intermediate has been isolated. A conformational study of this onium intermediate and a thermal unimolecular syn-elimination process may explain the stereoselectivity of the reaction. Such
Treatment of aliphatic carbonylcompounds with trimethylsilyl chloride with Mg turning for Grignard reaction without any pre-treatment in N,N-dimethylformamide at room temperature brought about highly facile, effective and stereoselective coupling to give the corresponding silylenolethers in good yields.
Synthesis of Optically Active α-Hydroxy Carbonyl Compounds by the Catalytic, Enantioselective Oxidation of Silyl Enol Ethers and Ketene Acetals with (Salen)manganese(III) Complexes
作者:Waldemar Adam、Rainer T. Fell、Veit R. Stegmann、Chantu R. Saha-Möller
DOI:10.1021/ja9726668
日期:1998.2.1
A set of silyl enol ethers and ketene acetals 1a−h with α- and/or β-phenyl as well as alkyl substituents of different steric bulk has been submitted to the enantioselective catalytic oxidation by chiral (salen)MnIII complexes 3. Highest conversions and best enantioselectivities have been obtained with bleach rather than iodosobenzene as oxygen source for the active oxo−metal species. With regard to
Highly Stereoselective Oxazaborolidinium Ion Catalyzed Synthesis of (<i>Z</i>)-Silyl Enol Ethers from Alkyl Aryl Ketones and Trimethylsilyldiazomethane
作者:Byung Chul Kang、Su Yong Shim、Do Hyun Ryu
DOI:10.1021/ol500174q
日期:2014.4.18
Highly stereoselective (Z)-silyl enol ethers were prepared fromalkylarylketones and trimethylsilyldiazomethane (TMSD) using an oxazaborolidinium ion catalyst. In addition, ring-expanded silyl enol ethers were successfully constructed from cyclic ketones. Their synthetic utilities were shown by sequential Mukaiyama aldol and [2 + 2]-cycloaddition reactions.