反应详情

2-tert-Butoxycarbonylamino-4-methyl-thiazole-5-carboxylic acid (0.52 g) was dissolved in THF: MeOH (2:1, 10 mL) and 2 eq of TMSCHN2 (2M sln in hex) was added at RT and stirred for 6 h. All volatiles were removed in vacuum by rotavap and the residue was dried in vacuum to give 2-tert-Butoxycarbonylamino-4-methyl-thiazole-5-carboxylic acid methyl ester (0.52 g). This was used in the next reaction without further purification. 1H NMR (400 MHz, CDCl3) 3.83 (s, 3H), 2.65 (s, 3H), 1.54 (s, 9H).

1. customAll volatiles were removed in vacuum by rotavap
2. customthe residue was dried in vacuum