Triethylamine → Tert-butyl 3-(2-(benzo[d]isothiazol-3-ylamino)ethylcarbamoyl)piperidine-1-carboxylate

Participants

Reaction Steps

A mixture of N1-(benzo[d]isothiazol-3-yl)ethane-1,2-diamine (600 mg, 3.11 mmol), 1-(tert-butoxycarbonyl)piperidine-3-carboxylic acid (854 mg, 3.7 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (585 mg, 3.7 mmol) and triethylamine (577 μL, 3.7 mmol) in dichloromethane (40 mL) was allowed to stir at room temperature overnight. The reaction mixture was washed successively with 1N aqueous hydrochloric acid, saturated sodium bicarbonate solution and water, then dried over anhydrous sodium sulfate, filtered and the filtrate concentrated under reduced pressure. Purification by flash column chromatography, on silica gel, eluting with a mixture of 25% ethyl acetate in hexanes gave fractions that were combined and concentrated under reduced pressure to yield tert-butyl 3-(2-(benzo[d]isothiazol-3-ylamino)ethylcarbamoyl)piperidine-1-carboxylate as a white solid, (325 mg). 1H NMR (300 MHz, DMSO-d6): 8.1 (m, 2H), 7.92 (m, 3H), 7.9 (d, 1H), 7.5 (m, 1H), 7.3 (m, 1H), 3.9 (m, 2H), 3.5 (m, 2H), 3.3 (m, 2H), 2.8 (m, 2H), 2.2 (m, 1H), 1.8 (m, 1H), 1.6 (m, 3H), 1.3 ppm (s, 9H). MW=405 confirmed by LC-MS, tr=3.81 min (Method B) MH+=406.

Provenance & Evidence