反应详情

A solution of crude 25.8 g (77 mmol) of the above prepared [4-(tert-butoxycarbonyl-methyl-amino)-2-methyl-phenoxy]-acetic acid methyl ester in 600 ml CH2Cl2 was treated at 0° C. with 198 ml TFA and stirred at RT for 30 min. The reaction was evaporated and treated with chilled aqueous saturated NaHCO3 solution/Et2O (3×). The organic phases were washed with aqueous 10% NaCl, dried over sodium sulfate, and evaporated to give 16.2 g of crude product. Purification by flash chromatography on SiO2 with a gradient of n-heptane: AcOEt (9:1 to 4:1) yielded 12.7 g of (2-methyl-4-methylamino-phenoxy)-acetic acid methyl ester as an orange oil.

1. customThe reaction was evaporated
2. additiontreated with chilled aqueous saturated NaHCO3 solution/Et2O (3×)
3. washThe organic phases were washed with aqueous 10% NaCl
4. dry with materialdried over sodium sulfate
5. customevaporated
6. customto give 16.2 g of crude product
7. customPurification by flash chromatography on SiO2 with a gradient of n-heptane: AcOEt (9:1 to 4:1)