2,6-Diiodopyrazine → 2-(6-Iodo-pyrazin-2-yl)-4-methyl-thiazole-5-carboxylic acid benzylamide

Participants

Reaction Conditions

Reaction Steps

Part B. An oven-dried sealed tube was charged with 2-bromo-4-methyl-thiazole-5-carboxylic acid benzylamide (800 mg, 2.57 mmol, 1.0 equiv). The sealed tube was purged with nitrogen and Rieke zinc (10 mL, 10 g of zinc in 100 mL of tetrahydrofuran) was added. The reaction was heated in the microwave oven for 15 min. at 100° C. Stirring was stopped and the remaining zinc was allowed to settle. The supernatant containing the zinc reagent was transferred via syringe to a solution of 2,6-diiodopyrazine (680 mg, 2.1 mmol, 0.8 equiv), Pd(PPh3)4 (236 mg, 0.2 mmol, 7 mol %) in tetrahydrofuran (5 mL) and dimethyl formamide (0.2 mL). The reaction mixture was purged with nitrogen for 10 min, then stirred at 160° C. for 16 hr. After cooling, the solvent was removed in vacuo and the crude product was purified by column chromatography [SiO2, ethyl acetate/heptane, 10:90 to 40:60, v/v] to afford 2-(6-iodo-pyrazin-2-yl)-4-methyl-thiazole-5-carboxylic acid benzylamide (140 mg, 13%). MS (M+H)+=436, Rt=1.51 min.

Provenance & Evidence