Mukaiyama–Michael addition of a ketenesilylacetal on a cyclic α,β-unsaturated ketone, followed by the addition of a glyoxylic, aromatic or heteroaromatic imine. According to the nature of the silyl group the adducts resulting from this tandem process are isolated as ketones or as enoxysilanes. The presence of a coordinating group on the imine increases the rate of the reaction.
Studies on the Electronic Absorption Spectra of Some Selected Furan Derivatives. Molecular Orbital Calculations
作者:Rafie Hassan Abu-Eittah、Maher Mohamed Hammed
DOI:10.1246/bcsj.57.844
日期:1984.3
The electronicabsorptionspectra of three groups of furan derivatives: 2-formyl, 2-acetylfuran, and 2-furoic acid, N-(2-furylmethylene)amines and phenylfurans were investigated. The predominant conformation as well as the polarity of the molecule could be predicted from its spectrum. The investigated molecules were proved to be “all planar” configuration which led to substantial interaction between
Ag-Catalyzed Asymmetric Mannich Reactions of Enol Ethers with Aryl, Alkyl, Alkenyl, and Alkynyl Imines
作者:Nathan S. Josephsohn、Marc L. Snapper、Amir H. Hoveyda
DOI:10.1021/ja049388e
日期:2004.3.1
An efficient catalytic and enantioselective method (up to >98% ee) for Mannich reactions between trimethylsilyl enol ethers derived from acetone and acetophenone and aryl, alkenyl, alkynyl, and alkyl imines is disclosed. A large variety of beta-amino ketones can be synthesized in the presence of 1-5 mol % AgOAc and an inexpensive and readily available amino acid-derived phosphine. All Ag-catalyzed
Asymmetric Mannich-Type Reactions of Aldimines with a Chiral Acetate
作者:Susumu Saito、Keiko Hatanaka、Hisashi Yamamoto
DOI:10.1021/ol000099e
日期:2000.6.1
strongly on the use of o-alkoxy (or o-fluoro) aniline-derived aldimines which have been found to have a potential effect on the enolate addition. This scope was expanded to the asymmetric process using the chiral acetate. A Lewis acid additive has a complementary role in the pronounced activation of imine functionalities.
β-Amino esters via the Reformatsky reaction: Restraining effects of the ortho-methoxyphenyl substituent
作者:James C. Adrian、Julia L. Barkin、Lamyaa Hassib
DOI:10.1016/s0040-4039(99)00248-8
日期:1999.3
β-Amino esters are, in most cases, the only products of the Reformatskyreaction in CH2Cl2 between (methoxycarbonyl)methyl zinc bromide (prepared in-situ) and imines prepared from either an aryl or alkyl aldehyde and o-anisdine (Scheme 2). Restraining properties of the ortho-methoxyphenyl group, which lead to sole formation of the β-amino ester, are ascribed to the inductive effect of the ortho-methoxy