1H-Indazole-4-boronic acid → HCID 86691498, compound

Participants

Reaction Steps

Tetraisopropyl (2-(2-chloropyridin-4-yl)-1-fluoroethane-1,1-diyl)bis(phosphonate) (78 mg; 0.16 mmol), Pd(PPh3)4 (37 mg; 0.032 mmol) and (1H-indazol-4-yl)boronic acid (52 mg; 0.32 mmol) are mixed in microwave vial (2-5 mL). The vial is capped with a septum, 2.0 mL of DME is added and the reaction mixture is immediately flushed with argon. Sodium carbonate solution (0.20 mL; 2M) is added and the mixture is flushed again with argon. The vial is re-capped with Teflon cap and irradiated in microwave for 15 min at 110° C. The mixture is cooled, diluted with EtOAc and filtered through Celite™, the Celite™ is rinsed 3× with EtOAc/MeOH (1:1). The filtrates are concentrated and deposited on silica. Purification by column chromatography on silica gel (pre treated with 1% NEt3 in hexanes) using a solvent gradient from hexanes to EtOAc, and then to 50% MeOH in EtOAc lead to the isolation of the product as a yellow oil (28 mg; 31% yield).

Provenance & Evidence