Dimethylcarbamoyl Chloride → HCID 118136146、化合物

Commercial (2R,3R)-benzyl 3-amino-2-methylpiperidine-1-carboxylate (323, CAS: 104461-49-7) (900 mg, 3.63 mmol) was dissolved in 30 mL MeCN and stirred at RT. To it were added DIEA (1.89 mL, 10.89 mmol) and then drop-wise dimethylcarbamoyl chloride (1.00 mL, 10.89 mmol). The mixture was stirred for overnight, concentrated on rotavap, diluted with EtOAc, washed with water ×2, dried over MgSO4, concentrated on rotavap, subjected to silica flash column using 0 to 4% MeOH in DCM to give (2R,3R)-benzyl 3-(3,3-dimethylureido)-2-methylpiperidine-1-carboxylate (324). It was dissolved in 100 mL iPrOH, and subjected to hydrogenation at 35 psi on Parr shaker with 10% Pd/C (1.0 g) for overnight. The mixture was filtered through celite, and the filtrate was concentrated in vacuo to afford 1,1-dimethyl-3-((2R,3R)-2-methylpiperidin-3-yl)urea (325) as a thick oil. It was dissolved in 30 mL dry DMF. To it were added 3,5-dichloropyrazine-2-carbonitrile (630 mg, 3.6 mmol) and then DIEA (1.25 mL, 7.2 mmol). The mixture was stirred at RT for overnight. It was diluted with 300 mL EtOAc, washed with water ×3, dried over MgSO4, concentrated on rotavap, and subjected to silica flash column with 0 to 4% MeOH in DCM to isolate 3-((2R,3R)-1-(6-chloro-5-cyanopyrazin-2-yl)-2-methylpiperidin-3-yl)-1,1-dimethylurea (326) (850 mg, 73% overall yield for three steps).