Rhizopus arrhizus-mediated asymmetric reduction of arylalkanones: unusual anti-Prelong products with benzyl alkyl ketones
摘要:
Rhizopus arrhizus-mediated microbial reduction of various aryl alkyl ketones afforded chiral carbinols in good yields and high enantiomeric purity. The most striking feature was the formation of the anti-Prelog (R)-alcohols with the benzyl alkyl ketones, while the other ketones ArXCOR (X = (CH2)(n), n = 0 or 2, OCH2 or SCH2 and R = Me/Et/n-Bu) furnished (S)-alcohols. (C) 2011 Elsevier Ltd. All rights reserved.
Regio-, stereo-, and chemoselectivering opening of epoxides with thiols using Cu/MgO as a heterogeneous catalyst has efficiently been carried out to produce the corresponding β-hydroxy sulfides in excellent yields at room temperature under solvent-free conditions. The treatment of the epoxides with thiols and 50% aqueous H2O2 in the presence of the same catalyst at room temperature affords the β-hydroxy
Racemic beta- and gamma-hydroxy sulfides were resolved by Humicola lanuginosa lipase catalyzed transesterification using vinyl acetate both as acyl donor and solvent. The effect of substituents and spacer length on rate of reaction and enantioselectivity is observed.
Abstract Epoxides are regioselectively cleaved by zinc thiolate intermediate, generated from disulfides in the presence of Zn/AlCl3 system, to afford high yields of the corresponding β-hydroxy sulfides.
Cytotoxic compounds. Part XIII. Some 1-arylthiopropan-2-ols and 2-arylthiopropanols. Rearrangement of the primary methanesulphonates into the secondary isomers
作者:M. S. Khan、L. N. Owen
DOI:10.1039/j39710001448
日期:——
naphthyl compounds. Except for the 2,4-dinitrophenyl derivative (prepared in the normal way with methanesulphonyl chloride) the secondarymethanesulphonates could only be obtained by the use of methanesulphonic anhydride under special conditions. Of the primary alcohols, the 2,4-dinitrophenyl compound gave the primarymethanesulphonate but all the others gave mainly the secondarymethanesulphonates.
Complex catalyst, process for producing the complex catalyst, and process for producing alchohol derivative with the complex catalyst
申请人:——
公开号:US20040077487A1
公开(公告)日:2004-04-22
There are provided (asymmetric) complex catalysts comprising metal complexes and Lewis acids as components, the metal complex being of formula (1):
1
wherein R
1
, R
2
, R
3
, R
4
, R
5
, R
6
, R
7
and R
8
are the same or different and are independently hydrogen, halogen, alkyl or the like; one of R
9
and R
10
is hydrogen and the other is alkyl of 1 to 4 carbon atoms or the like; Q is a single bond or alkylene of 1 to 4 carbon atoms; M is a metal ion; and A is a balancing counter ion or ligand; processes for the production of these complex catalysts; processes for the production of (optically active) alcohol derivatives, characterized in that cyclic ether compounds are reacted with phenol derivatives in the presence of these complex catalysts; and further processes for producing (optically active) nitrogen-containing heterocyclic compounds by reacting these alcohol derivatives with halogenated nitrogen-containing heterocyclic compounds in the presence of a base.