反应详情

2,6-Difluorobenzoyl isocyanate (1.4 g) in a 1:1 (v/v) mixture of toluene and petroleum ether (10 ml) was added to a solution of the compound produced by Example 6 (3 g) in the same solvent (15 ml), at ambient temperature. The solution was stirred for two hours and placed in a freezer overnight (-5° to 0° C.). The solvent was removed by evaporation, and the residue was chromatographed twice on silica, firstly using dichloromethane as eluant and secondly using a 1:1 (v/v) mixture of diethyl ether and petroleum ether, to yield the title compound (2.5 g), m.p. 77°-80° C.

1. waitplaced in a freezer overnight
2. custom(-5° to 0° C.)
3. customThe solvent was removed by evaporation
4. customthe residue was chromatographed twice on silica, firstly using dichloromethane as eluant
5. additiona 1:1 (v/v) mixture of diethyl ether and petroleum ether