反应详情

A solution of 6.2 g of 2-methoxycarbonyl-3-thienylsulfonylisocyanate in 50 ml of absolute tetrahydrofuran is stirred dropwise into a solution of 4.4 g of 2-amino-4-difluoromethoxy-6-methylpyrimidine in 80 ml of absolute tetrahydrofuran. During the course of this addition, the temperature of the reaction mixture rises from 20° to 26° C. After it has been stirred for another hour, the raction mixture is filtered and the filtrate is concentrated. The residue is crystallised from ethyl acetate, affording 5.3 g (50%) of N-(2-methoxycarbonyl-3-thienylsulfonyl)-N'-(4-difluoromethoxy-6-methylpyrimidin-2-yl)urea (compound 2.1) with a melting point of 178°-179° C.

1. additionDuring the course of this addition
2. customrises from 20° to 26° C
3. filtrationthe raction mixture is filtered
4. concentrationthe filtrate is concentrated
5. customThe residue is crystallised from ethyl acetate