ethyl 2-hydroxy-2,2-diphenylacetate

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: The product of Example 38 (0.5 g, 1.32 mmol) was dissolved in 15 mL THF to which was added carbonyldiimidazole (0.24 g, 1.48 mmol). The solution was stirred at room temperature for one hour. NaH (60% dispersion in mineral oil, 0.08 g, 3.2mmol) was washed (2×) with hexanes then suspended in THF (10 mL) to which was added ethyl benzilate (0.40 g, 3.2 mmol). After 20 minutes, the imidazolide intermediate was added dropwise to the solution of alcoholic anion and stirring continued at room temperature overnight. The solution was poured into 4-5 volumes of water and extracted with Et2O (2×100 mL). The organics were dried over MgSO4 and concentrate to a yellow oil (0.60 g). Product was chromatographed on medium column using silica gel (230-400 mesh) with isocratic 80/20 petroleum ether/ethyl acetate as the mobile phase. Elution and concentration gave α-(methoxyimino)-N-methyl-2-[[[3-chloro-5-(ethoxycarbonyldiphenylmethoxycarbonyl)-2-pyridinyl]oxy]methyl]-benzeneacetamide (0.50 g) as a yellow solid. After 20 minutes stirring continued at room temperature overnight extracted with Et2O (2×100 mL) The organics were dried over MgSO4 concentrate to a yellow oil (0.60 g) Product was chromatographed on medium column Elution and concentration