ethyl 2-hydroxy-2-phenylacetate

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of Novozym® 435 (2.21 g), molecular sieves (18.60 g), 1-dodecanol (3.76 g), and ethyl mandelate (3.61 g) in a 150 mL beaker was maintained at 60° C. in a convection oven for 28 hours. Upon work-up, 4.0 g of lauryl mandelate (56% yield) was obtained as a clear viscous liquid. The purity of the product was >95% as assessed by HPLC-DAD.

反応条件: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of Novozym® 435 (2.21 g), molecular sieves (18.60 g), 1-dodecanol (3.76 g), and ethyl mandelate (3.61 g) in a 150 mL beaker was maintained at 60° C. in a convection oven for 28 hours. Upon work-up, 4.0 g of lauryl mandelate (56% yield) was obtained as a clear viscous liquid. The purity of the product was >95% as assessed by HPLC-DAD.

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A 100 mL three-neck flask, equipped with a magnetic stir bar, a Claisen adapter with a thermocouple and a subsurface nitrogen inlet, and a short path condenser, was charged with 7.94 grams of ethyl mandelate, 40 mL of 1-pentanol, and 0.75 gram of p-toluenesulfonic acid. The reaction was stirred at 120°-132° C. for 4.0 hours with a nitrogen sweep. The reaction mixture was taken up in butyl acetate, extracted with dilute aqueous sodium hydroxide, washed three times with water, dried over magnesium sulfate, and filtered. Solvent was removed by rotary evaporation to yield 8.3 grams of a straw-colored liquid. A 100 mL three-neck flask, equipped with a magnetic stir bar extracted with dilute aqueous sodium hydroxide washed three times with water dried over magnesium sulfate filtered Solvent was removed by rotary evaporation

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A 100 mL three-neck flask, equipped with a magnetic stir bar, a Claisen adapter with a thermocouple and a subsurface nitrogen inlet, and a short path condenser, was charged with 7.94 grams of ethyl mandelate, 40 mL of 1-pentanol, and 0.75 gram of p-toluenesulfonic acid. The reaction was stirred at 120°-132° C. for 4.0 hours with a nitrogen sweep. The reaction mixture was taken up in butyl acetate, extracted with dilute aqueous sodium hydroxide, washed three times with water, dried over magnesium sulfate, and filtered. Solvent was removed by rotary evaporation to yield 8.3 grams of a straw-colored liquid. A 100 mL three-neck flask, equipped with a magnetic stir bar extracted with dilute aqueous sodium hydroxide washed three times with water dried over magnesium sulfate filtered Solvent was removed by rotary evaporation

反応条件: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of Novozym® 435 (2.21 g), molecular sieves (18.60 g), 1-dodecanol (3.76 g), and ethyl mandelate (3.61 g) in a 150 mL beaker was maintained at 60° C. in a convection oven for 28 hours. Upon work-up, 4.0 g of lauryl mandelate (56% yield) was obtained as a clear viscous liquid. The purity of the product was >95% as assessed by HPLC-DAD.

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: According to JP-A-11-193271, ethyl benzoylformate and cyclohexylmagnesium bromide are condensed to give ethyl 2-cyclohexyl-2-hydroxy-2-phenylacetate, which is hydrolyzed to give 2-cyclohexyl-2-hydroxy-2-phenylacetic acid. In this condensation reaction, diethyl ether having a boiling point of 35° C. is used in an amount of about 12-fold volume relative to ethyl benzoylformate, manipulation of dangerous reaction using the boiling point of diethyl ether is required and the yield is as low as 53.3%. In an attempt to improve this method into an industrially safe one, the present inventors used tetrahydrofuran instead of diethyl ether as a solvent and reproduced the reaction. As a result, there occurred reduction due to Grignard reagent to produce ethyl mandelate as a by-product, as well as addition of the Grignard reagent to ester bond. The proportion of the starting material that became a by-product was 42% and the yield of the objective product was as low as 58%. After hydrolysis of the obtained crude ethyl 2-cyclohexyl-2-hydroxy-2-phenylacetate, it was subjected to recrystallization and the like to increase the purity but the yield from ethyl benzoylformate of 2-cyclohexyl-2-hydroxy-2-phenylacetic acid did not exceed 43%. the reaction