Cesium carbonate → (R)-N-(6-methoxypyrimidin-4-yl)-4H-1'-azaspiro[oxazole-5,3'-bicyclo[2.2.2]octan]-2-amine

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Reaction Steps

To (S)-3-(aminomethyl)quinuclidin-3-ol dihydrochloride (0.363 g, 1.583 mmol) in N,N-dimethylformamide (20 mL) was added Cs2CO3 (1.289 g, 3.96 mmol) and 4-isothiocyanato-6-(3-methoxyphenyl)pyrimidine. The suspension was stirred at room temperature for 30 minutes. N,N′-diisopropylcarbodiimide (0.740 mL, 4.75 mmol) was then added and the mixture was continued to stir at room temperature for 18 hours. The mixture was concentrated and purified by silica gel chromatography (5-25% 9:1 methanol:ammonium hydroxide-ethyl acetate) to afford (R)—N-(6-methoxypyrimidin-4-yl)-4H-1′-azaspiro[oxazole-5,3′-bicyclo[2.2.2]octan]-2-amine (0.294 g, 0.788 mmol, 50% yield) as a a pale yellow solid. M.P 80-5° C. 1H NMR (400 MHz, MeOD) δ ppm 8.77 (1 H, s), 7.47-7.58 (2 H, m), 7.39 (1 H, t), 7.20 (1 H, br. s.), 7.04 (1 H, dd), 4.05 (1 H, d), 3.85 (3 H, s), 3.74 (1 H, d), 3.23 (1 H, d), 3.10 (1 H, d), 2.71-3.00 (4 H, m), 2.03-2.22 (2 H, m), 1.53-1.85 (3 H, m). MS (LC/MS) R.T.=1.58; [M+H]+=366.15.

Provenance & Evidence