Propargyl bromide → 2-(N-methyl-N-propynylamino)benzothiazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

2-Methylaminobenzothiazole (c) (14.0 g) was dissolved in anhydrous tetrahydrofuran (250 ml) and a hexane solution (73 ml) of butyl lithium (6.53 g) was added thereto at -78° C. with stirring. The mixture was stirred for 1.5 hours under cooling and 2-propynyl bromide (8.4 ml) was dropwise added thereto. The resultant mixture was allowed to stand at room temperature overnight and then evaporated to remove the solvent. After addition of water, the residue was extracted with ether. The extract was washed with water, dried and evaporated to remove the solvent. The resultant residue was applied to column chromatography on silica gel (280 g) to give 2-(N-methyl-N-propynylamino)benzothiazole (d) (14.5 g, yield 84%) from chloroform eluate.

Herkunft & Nachweise