Sodium Carbonate → HCID 117626446, compound

Participants

Reaction Conditions

Reaction Steps

To a stirred yellow solution of ethyl 6-(2-ethoxy-2-oxoacetyl)-7-chloro-5-methylpyrazolo[1,5-a]pyrimidine-2-carboxylate (264 mg, 0.777 mmol) in anhydrous toluene (5 mL) was added 1.0M (R)-1-methyl-3,3-diphenylhexahydropyrrolo[1,2-c][1,3,2]oxazaborole/toluene (0.311 mL, 0.311 mmol). The mixture was cooled to −35° C. and a solution of 50% catechoborane/toluene (0.272 mL, 1.088 mmol) was added over the course of 10 min. After 30 min, the reaction mixture was slowly warmed to −15° C. and stirred for additional 2 h, then diluted with EtOAc (30 mL) and sat.aq. Na2CO3 (5 mL). The mixture was stirred vigorously for 30 min, and the organic phase was washed with sat. aq. Na2CO3 (2×5 mL), dried (Na2SO4), filtered, concentrated. The residue was purified by silica gel chromatography (5-100% EtOAc/hexane) to afford the desired (S)-ethyl 7-chloro-6-(2-ethoxy-1-hydroxy-2-oxoethyl)-5-methylpyrazolo[1,5-a]pyrimidine-2-carboxylate (200 mg, 0.585 mmol, 75% yield) as an off-white solid. 1H NMR (400 MHz, CDCl3) δ 7.21 (s, 1H), 5.77 (d, J=2.7 Hz, 1H), 4.53 (d, J=7.1 Hz, 2H), 4.33 (dd, J=7.1, 5.5 Hz, 2H), 3.61 (br. s., 1H), 2.68 (s, 3H), 1.50-1.46 (t, J=7.09 Hz, 3H), 1.28 (t, J=7.09 Hz, 3H). LCMS (M+1)=342.13.

Provenance & Evidence