Sodium Carbonate → 4-(2-methoxy-4-nitrophenyl)-1-methyl-1H-pyrazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 2-(2-methoxy-4-nitro-phenyl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane (635 mg, 1.79 mmol) and 1-methyl-4-iodo-1H-pyrazole (745 mg, 3.58 mmol) in ethanol (11 mL) and toluene (26 mL) was purged with argon for 5 minutes. 1,1′-bis(diphenylphosphino)ferrocene palladium (II) chloride (73.0 mg, 0.89 mmol) was added and the mixture was heated to 80° C., then 2M aqueous sodium carbonate solution (14 mL) was added and stirring at 80° C. was continued for further 24 hours. The mixture was diluted with ethyl acetate, washed with water and brine, dried over magnesium sulfate and the solvent was evaporated. Column chromatography (20 g silica, dichloromethane) afforded the title compound (245 mg, 58%) as a yellow solid. MS ISP (m/e): 234.0 [(M+H)+]. 1H NMR (DMSO, 300 MHz): δ (ppm)=8.35 (s, 1H), 8.08 (s, 1H), 7.85 (m, 3H), 4.03 (s, 3H), 3.90 (s, 3H). Mp 132-134° C.

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