Cesium carbonate → (3R*,4R*)-N-(3,5-dichloropyridin-2-yl)-4'H-1-azaspiro[bicyclo[2.2.1]heptane-3,5'-oxazol]-2'-amine

Participants

Reaction Conditions

Reaction Steps

To a solution of 3,5-dichloro-2-isothiocyanatopyridine (57 mg, 0.279 mmol) in N,N-dimethylformamide (2 mL) was added (3S*,4R*)-3-(aminomethyl)-1-azabicyclo[2.2.1]heptan-3-ol dihydrochloride (60 mg, 0.279 mmol). The reaction was treated with cesium carbonate (227 mg, 0.697 mmol) and heated to 80° C. After 2 hours, the reaction was further treated with 1,3-diisopropylcarbodiimide (0.152 mL, 0.976 mmol). The reaction was heated at 80° C. for a further 18 hours and then cooled to room temperature. The reaction was poured into chloroform (20 ml) and water (20 ml). The organic was collected and purified by silica gel chromatography eluting with 5-40% (10% NH4OH/Methanol)/chloroform. The product fractions were collected and concentrated in vacuo followed by trituration in diethyl ether to yield (3R*,4R*)—N-(3,5-dichloropyridin-2-yl)-4′H-1-azaspiro[bicyclo[2.2.1]heptane-3,5′-oxazol]-2′-amine (42 mg, 0.134 mmol, 48%). 1H NMR (400 MHz, DMSO-d6) δ ppm 8.91 (s, 1H) 8.16 (d, J=2.26 Hz, 1H) 7.97 (d, J=2.51 Hz, 1H) 3.79 (d, J=10.04 Hz, 1H) 3.58 (d, J=9.79 Hz, 1H) 2.71-2.98 (m, 2H) 2.56-2.71 (m, 4H) 2.37 (dd, J=10.04, 3.76 Hz, 1H) 1.83-2.00 (m, 1H) 1.48 (s, 1H). MS (LC/MS) R.T=1.423; (M+H=312.99).

Provenance & Evidence