Comparing the Stereoselective Biooxidation of Cyclobutanones by Recombinant Strains Expressing Bacterial Baeyer–Villiger Monooxygenases
作者:Florian Rudroff、Joanna Rydz、Freek H. Ogink、Michael Fink、Marko D. Mihovilovic
DOI:10.1002/adsc.200700072
日期:2007.6.4
cyclobutanone structural motif was investigated using a collection of eight monooxygenases of different bacterial origin. This platform of enzymes is able to perform stereoselective biotransformations on an array of structurally diverse substrates. With several ketone precursors, biooxidations yielded enantiocomplementary butyrolactones as key intermediates for the synthesis of natural products and bioactive compounds
Exceptional activity of gallium(<scp>iii</scp>) chloride and chlorogallate(<scp>iii</scp>) ionic liquids for Baeyer–Villiger oxidation
作者:Magdalena Markiton、Anna Chrobok、Karolina Matuszek、Kenneth R. Seddon、Małgorzata Swadźba-Kwaśny
DOI:10.1039/c6ra03435g
日期:——
a range of metal chlorides in different solvents, and in neat chlorogallate(III) ionic liquids. The extremely high activity of GaCl3 in promoting oxidation with H2O2, irrespective of solvent, was reported for the first time. The activity of all other metal chlorides was strongly solvent-dependent. In particular, AlCl3 was very active in a protic solvent (ethanol), and tin chlorides, SnCl4 and SnCl2
使用H 2 O 2作为氧化剂,使用一系列金属氯化物在不同溶剂中和纯净的氯镓酸盐(III)离子液体中,系统研究了Bayerer-Villiger对环酮的氧化。首次报道了GaCl 3在促进H 2 O 2氧化方面的极高活性,而与溶剂无关。所有其他金属氯化物的活性都高度依赖溶剂。特别是,AlCl 3在质子溶剂(乙醇)中非常活泼,氯化锡,SnCl 4和SnCl 2,在非质子传递溶剂(甲苯和二恶烷)中具有活性。为了消除对挥发性有机溶剂的需求,使用路易斯酸性氯镓酸盐(III)离子液体代替GaCl 3,在环境条件下,其在1-120分钟内通常可产生89-94%的内酯收率。Raman和71 Ga NMR光谱研究表明,在GaCl 3和galgallate(III)离子液体系统中的活性物质均为chlorohydroxygallate(III)阴离子[GaCl 3 OH] -,它们是GaCl 3部分水解的产物。和氯
Conversion of olefins into γ-butyrolactones
作者:Stephen P. Brown、Balkrishna S. Bal、Harold W. Pinnick
DOI:10.1016/s0040-4039(01)92374-3
日期:1981.1
Cyclopropyl esters derived from olefins undergo ring opening with iodotrimethylsilane and, after base treatment, γ-butyrolactones are obtained.
衍生自烯烃的环丙基酯与碘代三甲基硅烷发生开环反应,经过碱处理后,获得γ-丁内酯。
Silyl peroxides as effective oxidants in the Baeyer–Villiger reaction with chloroaluminate(III) ionic liquids as catalysts
liquid: 0.67) present in the oxidation of cyclic ketones with bis(silyl) peroxides acts as the catalyst. In this variant of the reaction, the reactivities of bis(silyl) peroxides decrease in the following order: bis(trimethylsilyl) peroxide > bis(vinyldimethylsilyl) peroxide > bis(phenyldimethylsilyl) peroxide > bis(diphenylmethylsilyl) peroxide. A variety of cyclic ketones such as cyclobutanone, 3-substituted
Conjugate addition of Grignard reagents to α,β-unsaturated esters: Preparation of alkylsilylketeneacetals.
作者:Armelle Magot-Cuvru、Luis Blanco、Jacques Drouin
DOI:10.1016/s0040-4020(01)96174-5
日期:1991.9
Alkylsilylketeneacetals have been prepared by a one-step copper-catalyzed 1,4-addition of Grignard reagents to acrylic, crotonic, methacrylic and 3,3-dimethylacrylic esters in the presence of ClSiMe3. Their Z/E ratio could be modified using CuI (in the presence of HMPA) or CuII salts (without HMPA).