Reaction Steps
In a gas tight vessel, a solution of 5-(1-(tert-butyldimethylsilyloxy)-7-phenylheptyl)-2H-tetrazole (16 mg, 0.043 mmol), 2-iodopyridine (7 μL, 0.064 mmol), CuI (1 mg, 0.004 mmol), K2CO3 (12 mg, 0.085 mmol), and N,N-dimethylethylene diamine (1 μL, 0.006 mmol) in DMF (200 μL) was purged with Ar and sealed. The reaction mixture was warmed at 100° C. for 18 h before it was cooled to room temperature, diluted with EtOAc, and washed with H2O, 9:1 NH4OH: saturated aqueous NH4Cl, and saturated aqueous NaCl. The organic layer was dried over Na2SO4 and the solvent was removed under reduced pressure to afford the crude material that was purified by flash chromatography (SiO2, 1.5×15 cm, 5-10% acetone-hexanes) to afford 2-(5-(1-(tert-butyldimethylsilyloxy)-7-phenylheptyl)-2H-tetrazol-2-yl)-pyridine (4.0 mg, 21%) as a colorless oil: 1H NMR (CDCl3, 400 MHz) δ 8.69 (dd, 1H, J=0.9, 4.8 Hz), 8.16 (d, 1H, J=7.5 Hz), 7.98 (dt, 1H, J=1.8, 7.9 Hz), 7.48 (m, 1H), 7.26 (m, 2H), 7.16 (m, 3H), 5.16 (dd, 1H, J=5.9, 7.4 Hz), 2.58 (t, 2H, J=7.7 Hz), 1.99 (m, 2H), 1.60 (m, 2H), 1.34 (m, 6H), 0.88 (s, 9H), 0.10 (s, 3H), −0.02 (s, 3H); 13C NMR (CDCl3, 150 MHz) δ 169.7, 149.6, 149.0, 142.9, 139.5, 128.5, 128.4, 125.7, 125.0, 115.2, 67.4, 37.5, 36.1, 31.5, 29.3, 25.9 (3C), 25.4, 18.4, −4.1, −4.8; HRMS-ESI-TOF m/z 452.2823 ([M+H]+, C25H37N5OSi requires 452.2840).
