2-Methylsulfanyl-pyrimidine-5-carboxylicacid methyl ester (323 mg, 1.75 mmol), Copper(I) thiophene-2-carboxylate (501 mg, 2.63 mmol), tetrakis(triphenylphosphine) palladium(0) (202 mg, 0.175 mmol) and 3-methoxyphenylboronic acid (400 mg, 2.63 mmol) are taken in a glass tube, evacuated, refilled with N2, added anhydrous THF (6 mL) and is heated overnight at 85° C. after closing with a cap. The reaction is cooled to rt, diluted with EtOAc and ammonium hydroxide is added. The organic layer is seperated, dried (MgSO4), filtered and concentrated in vacuo. The residue is purified by flash silica gel chromatography to afford 2-(3-methoxy-phenyl)-pyrimidine-5-carboxylic acid methyl ester (152 mg) as a powder. MS: 245 (M+H); 1H NMR (CDCl3): δ 4.00 (s, 3H), 4.82 (d, 2H), 7.55 (m, 2H), 8.46 (m, 1H), 8.53 (s, 1H), 9.33 (s, 2H).
