Methylamine → 2-(2,5-Dimethylthien-3-yl)-N-methylimidazo[2,1-b]-benzothiazole-3-acetamide

Participants

Reaction Conditions

Reaction Steps

A solution of 1.5 g (0.0044 mole) of 2-(2,5-dimethylthien-3-yl)imidazo[2,1-b]benzothiazole-3-acetic acid in 30 ml of anhydrous tetrahydrofuran is treated, at room temperature, with 0.85 g (0.005 mole) of N,N'-carbonyldiimidazole for 30 minutes. The solution which has become clear is cooled to 0° C. and a stream of methylamine is passed through it for 30 minutes. The mixture is allowed to return to room temperature, the stirring is continued for 3 h, the solvent is evaporated under reduced pressure, the residue is taken up in 10 ml of water, it is extracted with dichloromethane, the organic phase is separated, it is washed with water, it is dried over sodium sulphate, the solvent is evaporated under reduced pressure, and the residue is crystallized from ethyl acetate. 1 g of pale yellow crystals is finally obtained. Melting point: 238°-239° C.

Provenance & Evidence