反应详情

Methanesulphonic anhydride (1.392 g.) was added to a solution of ethyl 6-amino-4-hydroxycinnolin-3-yl carboxylate (0.932 g.) in dry pyridine (20 ml.), and the mixture was stirred at room temperature overnight. The resulting solution was poured into ether (500 ml.) and the amorphous solid which precipitated was filtered off and applied to a silica column (100 g. Kieselgel 60). Elution with a mixture of 15% v/v ethanol and 85% v/v chloroform, and evaporation of the appropriate fractions gave ethyl 4-hydroxy-6-(methanesulphonylamino)cinnolin-3-yl carboxylate, m.p. 274°-5° C.

1. customthe amorphous solid which precipitated
2. filtrationwas filtered off
3. washElution
4. additionwith a mixture of 15% v/v ethanol and 85% v/v chloroform, and evaporation of the appropriate fractions