[CH3:1][C:2]1[CH:3]=[C:4]([OH:17])[CH:5]=[CH:6][C:7]=1B1OC(C)(C)C(C)(C)O1.[CH2:18]([O:20][C:21]([C:23]1[C:27]2[CH:28]=[CH:29][C:30](Br)=[CH:31][C:26]=2[O:25][N:24]=1)=[O:22])[CH3:19]>O1CCOCC1>[CH2:18]([O:20][C:21]([C:23]1[C:27]2[CH:28]=[CH:29][C:30]([C:7]3[CH:6]=[CH:5][C:4]([OH:17])=[CH:3][C:2]=3[CH3:1])=[CH:31][C:26]=2[O:25][N:24]=1)=[O:22])[CH3:19]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 added to a flask. The flask is evacuated and re-filled with N2 3 times. To this solution, Pd2(dba)3 (0.010 g), tricyclohexyl phosphine (10 mg), and aqueous K3PO4 (1.5 mL, 1.30 M) are added. The resulting mixture is heated to 50° C. for 2 hours under N2. The reaction mixture is cooled to room temperature and filtered through a pad of diatomaceous earth. The filtrate is concentrated under reduced pressure. 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).
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