Nitrogen → 6-(4-Hydroxy-2-methyl-phenyl)-benzo[d]isoxazole-3-carboxylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of 3-methyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenol (0.624 g, 2.67 mmol) and 6-bromo-benzo[d]isoxazole-3-carboxylic acid ethyl ester (0.360 g, 1.33 mmol) in 1,4-dioxane (20 mL) is evacuated and re-filled with N2 3 times. To this solution, Pd2(dba)3 (0.010 g), tricyclohexyl phosphine (PCy3, 10 mg), and aqueous K3PO4 (1.5 mL, 1.30 M) are added. The resulting mixture is heated at 50° C. for 2 hours under N2. The reaction mixture is cooled to room temperature and filtered through a pad of celite. The filtrate is concentrated, and the residue is purified via silica gel chromatography eluting with 25% ethyl acetate in hexanes to give the title compound (0.366 g, 93%). ES/MS m/e 298.0 (M+1); 296.0 (M−1).

Provenance & Evidence