- Preparation method of 2-(4-benzyloxyphenyl)ethanol
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The invention provides a preparation method of 2-(4-benzyloxyphenyl)ethanol. The preparation method comprises the following steps: 1) subjecting phenol to reacting with chloroacetyl chloride under the catalysis of aluminum trichloride to obtain a compound as shown in a formula II; 2) subjecting the compound as shown in the formula II to reacting with benzyl halide under an alkaline condition to obtain a compound as shown in a formula III, wherein the benzyl halide is one selected from benzyl bromide and benzyl chloride; 3) performing reduction treatment on the compound as shown in the formula III, and adjusting a reaction system to be an alkaline system to obtain a compound as shown in a formula IV; and 4) under the action of a catalyst, reducing the compound as shown in the formula IV under a hydrogen condition to obtain the 2-(4-benzyloxyphenyl)ethanol as shown in the formula I. The preparation method has the advantages of low cost, mild reaction conditions, safety in operation and less three-waste pollution, and is beneficial to being applied to industrial production.
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Paragraph 0063; 0068-0070; 0080-0083; 0092; 0093
(2021/08/06)
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- High-yielding aqueous synthesis of chloroacetophenones and aroyl chlorohydrins
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The use of large amounts of volatile organic solvents in industrial chemical processes contributes to widespread environmental pollution. To help solve this problem, water and a phase transfer catalyst were used to replace organic solvents in the transformations of bromoacetophenones into chloroacetophenones and aroyl epoxides into aroyl chlorohydrins. The reactions were promoted by sulfonyl chlorides and gave quantitative or close to quantitative yields. Notably, chromatographic purification, which is laborious and consumes large amounts of organic solvents, was not needed. These two processes have opened a green and cost-effective channel to prepare the chemical intermediates chloroacetophenones and aroyl chlorohydrins. The reaction mechanisms are discussed based on control experiments.
- Zhang, Xixi,Liu, Lei,Li, Chunbao
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p. 25339 - 25345
(2016/03/22)
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- Chemoenzymatic synthesis of enantiopure 1-phenyl-2-haloethanols and their esters
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Several secondary haloalcohols have been resolved by esterification catalyzed by lipases A and B from Candida antarctica (CALA and CALB, respectively). Immobilized CALB (Novozym 435) gave better selectivities and faster reaction rates than CALA (Novozyme
- Lystvet, Sina Maria,Hoff, Bard Helge,Anthonsen, Thorleif,Jacobsen, Elisabeth Egholm
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experimental part
p. 272 - 278
(2011/11/30)
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- Microwave assisted fluorination: an improved method for side chain fluorination of substituted 1-arylethanones
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A two-step, one-pot microwave (MW) assisted fluorination of 1-arylethanones to their corresponding 1-aryl-2-fluoroethanones has been developed. The first step utilises Selectfluor as a fluorinating agent in methanol forming 1-aryl-2-fluoroethanones and their corresponding dimethyl acetals. In the second step, water is added and Selectfluor acts as a Lewis acid in the hydrolytic cleavage of the dimethyl acetals. Compared to the thermal synthesis, the MW assisted method leads to a reduction in reaction time both in the fluorination and for the dimethyl acetal cleavage. Moreover, the one-pot procedure reduces reagent and solvent consumption. The method is best suited for the preparation of 1-aryl-2-fluoroethanones containing substituents that deactivates electrophilic aromatic substitution, however highly electron deficient ketones such as 1-(3,5-dinitrophenyl)ethanone reacts more slowly. Reactions using electron rich aromatic ketones had a low regioselectivity, and also produced fluoroaromatic products.
- Krane Thvedt, Thor H?kon,Fuglseth, Erik,Sundby, Eirik,Hoff, B?rd Helge
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experimental part
p. 9550 - 9556
(2010/02/27)
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