Phenylacetylene → HCID 24970980, compound

Participants

Reaction Steps

2-tert-butoxycarbonylamino-5-(4-iodophenyl)imidazole-1-carboxylic acid tert-butyl ester (0.100 g, 0.206 mmol) was dissolved in anhydrous THF (8 mL) and to this solution was added DIPEA (0.359 mL, 2.06 mmol), CuI (0.004 g, 0.021 mmol), and PdCl2(PPh3)2 (0.014 g, 0.021 mmol). The solution was then degassed at ambient temperature for 10 minutes. During this time a solution of the phenyl acetylene (0.105 g, 1.03 mmol) in anhydrous THF (3 mL) was also degassed. The solution of alkyne was added drop-wise to the solution of aryl iodide and the reaction was stirred at room temperature for 12 h. The reaction was filtered through a Celite® pad and the filter cake rinsed with EtOAc (10 mL). The filtrate was washed with sat. NH4Cl (2×10 mL), brine (2×10 mL), and dried (Na2SO4). Filtration and evaporation afforded the crude product which was purified via flash column chromatography (10-50% EtOAc/Hexanes) to obtain 0.085 g (90%) of the target 2-tert-butoxycarbonylamino-5-(4-phenylethynylphenyl) imidazole-1-carboxylic acid tert-butyl ester as a yellow solid: mp=131-132° C.; 1H NMR (400 MHz, DMSO-d6) δ 9.60 (s, 1H), 8.00 (s, 1H), 7.86 (d, 2H, J=7.6 Hz), 7.42-7.57 (m, 7H), 1.58 (s, 9H), 1.44 (s, 9H); 13C NMR (100 MHz, DMSO-d6) δ 152.9, 146.8, 139.9, 136.3, 133.0, 131.7, 131.4, 128.8, 124.9, 122.4, 126.8, 120.9, 113.7, 89.9, 89.5, 85.4, 80.1, 27.9, 27.3; HRMS (ESI) calcd for C27H19N3O4Na (MNa+) 482.2050. found 482.2051.

Provenance & Evidence