2-Bromothiazole-5-carboxylic acid → HCID 66654677, compound

Participants

Reaction Conditions

Reaction Steps

Bubble argon through a suspension of 2-bromothiazole-5-carboxylic acid (75 mg, 0.36 mmol), 2-picoline-4-boronic acid (59 mg, 0.43 mmol), and tetrakis-(triphenylphosphine)-palladium(0) (42 mg) in NMP (1 mL) and 2M Na2CO3 (0.25 mL). Stir the sealed vial at 100° C. for 4 h. Quench the reaction with aq. NH4Cl and concentrate in vacuo. Triturate the residue in 30% MeOH/DCM, filter, and concentrate the filtrate in vacuo to an oil. Addition of H2O gives a precipitate. Filter the solid, wash with H2O and ether, and dry to give a residue containing impure product. Extract the aqueous filtrate with 1:1 EtOAc/n-butanol (4×), wash with H2O (4×), and concentrate in vacuo to get more impure product. Purify both crops by prep-TLC developing with 10% MeOH/DCM with 1% HOAc. Further purify the desired band by the same method developing with 50% MeOH/DCM to give desired product 2-(2-methyl-pyridin-4-yl)-thiazole-5-carboxylic acid as a resin (8 mg, 0.036 mmol). MS, electrospray (M+H) 221.5, rt 0.51 min.

Provenance & Evidence