Dichloromethane → 1-(2,3,5,6-tetrafluorophenyl)-1H-pyrazolo[3,4-b]pyridin-4-ylboronic acid

Participants

Reaction Conditions

Reaction Steps

To a 48 mL pressure bottle under N2 was added the compound from Intermediate 69A (1.1 g, 2.8 mmol), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane (1.17 g, 4.61 mmol), potassium acetate (1.15 g, 11.72 mmol), and anhydrous DMSO (8 mL). Argon was bubbled into the reaction mixture for 5 min and then PdCl2(dppf).CH2Cl2 (71 mg, 0.097 mmol) was added. The reaction mixture was flushed with argon, securely capped, and heated at 105° C. for 75 min. After adding 30 mg more palladium catalyst and 60 mg more 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane, the reaction mixture was heated at 115° C. in an oil bath for an additional 75 min to give the desired intermediate. LC/MS (Condition B): ret. T=3.2 min, (M+H)+ 312.03.

Provenance & Evidence