Sodium Carbonate → cyclopropanecarboxylic acid [4-bromo-3-(2-methyl-2H-indazol-5-yl)-isothiazol-5-yl]-amide

Participants

Reaction Steps

Degas by bubbling nitrogen for 10; min through a mixture of cyclopropanecarboxylic acid (3,4-dibromo-isothiazol-5-yl)-amide (1.04; g, 3.19; mmol) and 2-methyl-5-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-2H-indazole (1.29; g, 3.51 mmol) in 1,4-dioxane (16; mL) and a 2M aqueous solution of sodium carbonate (7.98 mL). Add bis(triphenylphosphine)palladium(II) chloride (448; mg, 0.64; mmol) and heat at 80° C. for 12; h. Cool, dilute with brine and ethyl acetate and separate the layers. Extract the aqueous phase twice with ethyl acetate. Dry the combined organic phases over sodium sulfate, filter, concentrate and purify by silica gel chromatography, gradient eluting from 40:60; to 100:0; using ethyl acetate:hexanes, to give the title compound as a solid (0.6; g, 1.59; mmol, 50%). MS (m/z): 377, 379; (M+1).

Provenance & Evidence