Diastereoselective Synthesis of Nitroaldol Derivatives
作者:Dieter Seebach、Albert K. Beck、Triptikumar Mukhopadhyay、Elizabeth Thomas
DOI:10.1002/hlca.19820650402
日期:1982.6.16
Three methods are described by which diastereomerically enriched nitroaldols and their O-silylated derivatives can be prepared. threo-Nitroaldols prevail up to 10:1 over the erythro-isomers if doubly deprotonated nitroaldols 28 are quenched with acetic acid (THF/HMPT or DMPU, − 100°) (see Scheme 5 and Table 2). O-Trimethyl- or O-(t-butyl)dimethylsilylated (TBDMSi) erythro-nitroaldols can be obtained
Asymmetric Henry Reactions Catalyzed by Metal Complexes of Chiral Boron-Bridged Bisoxazoline (borabox) Ligands
作者:Aurélie Toussaint、Andreas Pfaltz
DOI:10.1002/ejoc.200800570
日期:2008.9
Metalcomplexes of boron-bridgedbisoxazolines (boraboxligands) were evaluated as catalysts for the Henryreaction. Copper(II) complexes induced high enantio- and diastereoselectivity in reactions with nitroethane and nitropropane. The amount of base added had a strong influence on the formation of the chiralcomplex and the enantioselectivity. Comparison with the corresponding dimethylmethylene-bridged
Catalytic anti-selective asymmetric Henry (nitroaldol) reaction catalyzed by Cu(I)–amine–imine complexes
作者:Yao Qiong Ji、Gao Qi、Zaher M.A. Judeh
DOI:10.1016/j.tetasy.2011.12.010
日期:2011.12
derived from N-methyl-C1-tetrahydro-1,1′-bisisoquinolines (R)-1b and Cu(I)Cl promoted the diastereoselective Henry reaction of nitroethane with a series of aromatic and aliphatic aldehydes. The nitroalcohol adducts were obtained in excellent yields (up to 95%), moderate anti-selectivity (up to 2.6:1), and good enantioselectivity (up to 92% ee) without any special precautions to exclude moisture or air
Environmentally Friendly Solvent-Free Processes: Novel Dual Catalyst System in Henry Reaction
作者:Apurba Bhattacharya、Vikram C. Purohit、Frank Rinaldi
DOI:10.1021/op020222c
日期:2003.5.1
Our environmentally benign synthesis of nitroalcohols involves a simple solvent-free condensation of an appropriate aldehyde with a 1-nitroalkane utilizing a novel dual catalytic system consisting of a mineral base and an appropriate surfactant under homogeneous conditions. By proper choice of the catalyst, base, and/or reaction conditions, the reaction can be performed to a level of >90% conversion as well as selectivity.