In a vial, a mixture of (S)-3-(3-bromopyrazolo[1,5-a]pyrimidin-5-yl)-4-isopropyloxazolidin-2-one (Example 1, Step 4; 1.82 g, 5.58 mmol), 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzoic acid (2.08 g, 8.37 mmol), and 2 M K2CO3 (8.37 mL, 16.7 mmol) in dioxane (20 mL) was degassed by bubbling N2 for 5 minutes. Pd2 dba3 (0.51 g, 0.56 mmol) and XPHOS (0.266 g, 0.558 mmol) were added and the reaction was capped under N2 and heated at 100° C. After 19 hours, the mixture was cooled to ambient temperature, diluted with EtOAc, washed with water and brine, dried over MgSO4, and concentrated under reduced pressure. The crude was purified by silica gel flash column chromatography (0-3% MeOH in dichloromethane) to afford 0.92 g (45%) of (S)-4-(5-(4-isopropyl-2-oxooxazolidin-3-yl)pyrazolo[1,5-a]pyrimidin-3-yl)benzoic acid. LCMS (APCI+) m/z 367.4 [M+H]+.
