Kinetic resolution of aliphatic acyclic β-hydroxyketones by recombinant whole-cell Baeyer–Villiger monooxygenases—Formation of enantiocomplementary regioisomeric esters
作者:Jessica Rehdorf、Alenka Lengar、Uwe T. Bornscheuer、Marko D. Mihovilovic
DOI:10.1016/j.bmcl.2009.05.014
日期:2009.7
substrates in the enzymatic kinetic and regioselective Baeyer–Villiger oxidation catalyzed by 12 Baeyer–Villigermonooxygenases from different bacterial origin. Excellent enantioselectivities (E >100) could be observed with 4-hydroxy-2-ketones. After acyl migration, the ester undergoes hydrolysis followed by the formation of optically active 1,2-diols. Furthermore, resolution of 5-hydroxy-3-ketones gave
Selective Monoacetylation of Symmetrical Diols and Selective Monodeacetylation of Symmetrical Diacetates Using HY-Zeolite as Reusable Heterogeneous Catalyst
作者:Biswanath Das、K. V. Srinivas、I. Mahender
DOI:10.1055/s-2003-42468
日期:——
HY-Zeolite has been found to be an efficient and reusable catalyst for selective monoacetylation of symmetrical diols and selective monodeacetylation of symmetrical diacetates to form the products in high yields.
Selective acylation of a sterically hindered hydroxyl group of unsymmetrical diols containing a primary hydroxyl group such as 1,5-hexanediol in the presence of silica gel with acetyl chloride
Highly Efficient, Regio- and Stereoselective Ring Opening of Epoxides and Thiiranes with Ce(OTf)<sub>4</sub>
作者:N. Iranpoor、M. Shekarriz、F. Shiriny
DOI:10.1080/00397919808005728
日期:1998.1
Abstract Cerictriflate, Ce(OTf)4 is used as an efficient catalyst for ring opening of epoxides in the presence of alcohols, water, and acetic acid. The reactions proceed with high regio and stereoselectivity and in excellent yields. The reaction of R(+) styrene oxide with methanol occurs with excellent optical purity. Ring opening of thiiranes in alcohols, water and acetic acid followed by dimerisation
Iron(III) Trifluoroacetate as an Efficient Catalyst for Solvolytic and Nonsolvolytic Nucleophilic Ring Opening of Epoxides
作者:Nasser Iranpoor、Hadi Adibi
DOI:10.1246/bcsj.73.675
日期:2000.3
Iron(III) trifluoroacetate was used as an efficient and nonhygroscopic catalyst for the alcoholysis, hydrolysis, and acetolysis of epoxides. The addition of chloride, bromide, iodide, and nitrate ions to epoxides to produce the corresponding 2-halo and 2-nitratoalkanols and also the conversion of epoxides to acetonides and thiiranes were also performed efficiently in the presence of this catalyst.