5-Nitrothiophene-2-sulfonyl chloride → (3S)-4-(((2S)-4-((5-nitro-2-thiophenyl)sulfonyl)-2-piperazinyl)methyl)-3-methylmorpholine

Participants

Reaction Steps

A 150-mL round-bottomed flask was charged with (3S)-3-methyl-4-((2R)-2-piperazinylmethyl)morpholine trihydrochloride (0.750 g, 2.43 mmol, step 3), TEA (2.03 mL, 14.6 mmol) and CH2Cl2 (10 mL). To this was added a solution of 5-nitrothiophene-2-sulfonyl chloride (0.560 g, 2.46 mmol, Enamine LLC, Monmouth Jct., NJ) in CH2Cl2 (5 mL). The reaction mixture was stirred at room temperature for 20 min. The reaction mixture was partitioned between water (20 mL) and CH2Cl2 (20 mL). The aqueous phase was extracted with CH2Cl2 (2×20 mL). The combined organic phases were washed with water (40 mL) and saturated aqueous NaCl (40 mL). The organic phase was dried over sodium sulfate, filtered and concentrated in vacuo. The crude product was purified by column chromatography (50 g of silica gel, 0 to 12.5% iPrOH (with 10% NH4OH) in CHCl3) to afford (3S)-4-(((2S)-4-((5-nitro-2-thiophenyl)sulfonyl)-2-piperazinyl)methyl)-3-methylmorpholine (0.797 g) as a light orange glass.

Provenance & Evidence