A mixture of 3-iodo-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-indazole-6-carbaldehyde (100 mg, 0.25 mmol), 3-(tetrazol-5-yl)phenylboronic acid (57 mg, 0.30 mmol), Pd(PPh3)4 (18 mg, 0.025 mmol) and 2M Na2CO3 (0.13 mL, 0.25 mmol) in DME/H2O/EtOH (2.8 mL/0.8 mL/0.4 mL) was degassed by evacuation and blanketed with Ar. The reaction mixture was sealed and heated with stirring under microwave irradiation at 125° C. for 4 hours. The crude reaction mixture was concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel using MeOH (5% to 10%) in DCM as the eluent to provide a white solid (40 mg, 38%). 1H NMR (400 MHz, CD3OD) δ ppm 10.10 (s, 1H), 8.59 (s, 1H), 8.25 (s, 1H), 8.21 (d, J=8.5 Hz, 1H), 8.11 (d, J=7.9 Hz, 1H), 8.04 (d, J=8.3 Hz, 1H), 7.77 (d, J=8.4 Hz, 1H), 7.67 (t, J=7.8 Hz, 1H), 5.88 (s, 2H), 3.66 (t, J=8.1 Hz, 2H), 0.89 (t, J=8.0 Hz, 2H), −0.10 (s, 9H); MS ESI 421.1 (100) [M+H]+, calcd for [C21H24N6O2Si+H]+ 421.2.
