反应详情

To a solution of ethyl 4-aminothiophene-2-carboxylate (Int. 41) (theoretical 1.785 mmol) in pyridine (20 ml), methanesulfonyl chloride (0.239 ml, 3.07 mmol) was added and the mixture was stirred overnight at RT. The solvent was evaporated and the residue was partitioned between 1N HCl and EtOAc; the aqueous phase was extracted with EtOAc and the combined organic layers were dried over sodium sulfate and evaporated to afford ethyl 4-(methylsulfonamido)thiophene-2-carboxylate (Int. 42) which was used without any additional purification (370 mg, 1.484 mmol, MS/ESI+249.8 [MH]+).

1. customThe solvent was evaporated
2. customthe residue was partitioned between 1N HCl and EtOAc
3. extractionthe aqueous phase was extracted with EtOAc
4. dry with materialthe combined organic layers were dried over sodium sulfate
5. customevaporated