Tetrahydrofuran → (S)-methyl 2-(2-(3-chlorophenyl)-7-isopropyl-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-hydroxyacetate

Participants

Reaction Conditions

Reaction Steps

To a stirred yellow solution of methyl 2-(2-(3-chlorophenyl)-7-isopropyl-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-oxoacetate (0.103 g, 0.277 mmol) in anhydrous toluene (5 mL) was added 1.1M (R)-1-methyl-3,3-diphenylhexahydropyrrolo[1,2-c][1,3,2]oxazaborole/toluene (0.101 ml, 0.111 mmol). The mixture was cooled to −35° C. and a solution of 1M catechoborane/THF (0.388 ml, 0.388 mmol) was added over 10 min. After 30 min, the reaction mixture was slowly warmed to −15 C and diluted with EtOAc (5 mL) and sat. Na2CO3 (2 mL). The mixture was stirred vigorously for 30 min, and the organic phase washed with sat Na2CO3 (2×5 mL), dried (Na2SO4), filtered, concentrated and the residue was purified by prep-HPLC to give (S)-methyl 2-(2-(3-chlorophenyl)-7-isopropyl-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-hydroxyacetate (0.0693 g, 0.185 mmol, 66.9% yield) as white solid. 1H NMR (500 MHz, CDCl3) δ: 7.99 (t, J=1.5 Hz, 1H), 7.86 (dt, J=7.4, 1.5 Hz, 1H), 7.41-7.33 (m, 2H), 6.80 (s, 1H), 5.63 (s, 1H), 3.81 (s, 3H), 3.40 (br. s., 1H), 2.62 (s, 3H), 1.68 (d, J=7.0 Hz, 3H), 1.59 (d, J=7.0 Hz, 3H). LCMS (M+H) calcd for C19H21ClN3O3: 374.13. found: 374.2.

Provenance & Evidence