反应详情

A solution of commercially available 2-methylbenzo[d]thiazole-5-carboxylic acid (1.500 g; 7.76 mmol) in anh. DMF (35 ml) was treated with Cs2CO3 (3.161 g; 9.70 mmol), and the heterogeneous mixture was further stirred at rt, under nitrogen, for 15 min. The mixture was then cooled to 0° C., and CH3I (1.652 g; 11.64 mmol) was added dropwise. The resulting mixture was further stirred at 0° C. for 10 min., and then at rt for 16 h. Water and AcOEt were added to the reaction mixture. The separated organic layer was further washed with water and brine, dried over anh. MgSO4, filtered, and concentrated to dryness under reduced pressure affording methyl 2-methylbenzo[d]thiazole-5-carboxylate as a brown solid. LC-MS (conditions A): tR=0.67 min.; [M+H]+: 208.16 g/mol.

1. temperatureThe mixture was then cooled to 0° C.
2. stirringThe resulting mixture was further stirred at 0° C. for 10 min.
3. waitat rt for 16 h
4. washThe separated organic layer was further washed with water and brine
5. dry with materialdried over anh. MgSO4
6. filtrationfiltered
7. concentrationconcentrated to dryness under reduced pressure