反应详情

9.68 g of crude product (0.0339 mol of methyl E/Z-2-(2-hydroxyphenyl)-2-methoxyimino-acetate, in particular compound II-1c from process step 6, HPLC: 43.7% E isomer of log p=1.48; 29.4% Z isomer of log p=2.37) are dissolved in 100 ml of tetrahydrofuran and cooled to 10° C. With cooling, methylamine is introduced. After about 30 minutes, 50 ml of methanol are added, the solution is saturated with methylamine and the mixture is allowed to stand at 10° C. overnight. The solvents are distilled off under reduced pressure and the residue is mixed with a mixture of 30 ml of 2N hydrochloric acid and 30 ml of saturated sodium chloride solution and extracted three times with 50 ml of ethyl acetate each time. The organic phase is dried over sodium sulphate and the solvent is distilled off under reduced pressure, giving 8.5 g of crude product which, according to HPLC, contains 52.6% N-methyl-E-2-(2-hydroxyphenyl)-2-methoxyimino-acetamide of log p=0.98 and 31.9% N-methyl-Z-2-(2-hydroxyphenyl)-2-methoxyiminoacetamide of log p=1.29.