Tetrabutylammonium Fluoride → 5-Cyano-1H-imidazole-2-carboxylic acid [2-cyclohex-1-enyl-4-(2-methyl-[1,3]dioxolan-2-yl)-phenyl]-amide

Participants

Reaction Steps

To a solution of 4-cyano-1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazole-2-carboxylic acid [2-cyclohex-1-enyl-4-(2-methyl-[1,3]dioxolan-2-yl)-phenyl]-amide (as prepared in the previous step, 45 mg, 0.088 mmol) in 3 mL of THF was added tetrabutyl ammonium fluoride (TBAF) (69 mg, 0.264 mmol). The reaction was stirred for 14 h at room temperature, at which time the temperature was raised to 60° C. for 15 min and then diluted with EtOAc (25 mL) and washed with water (3×25 mL). The organic layer was dried (Na2SO4) and concentrated in vacuo. Purification of the residue using preparative TLC (10% MeOH—CHCl3) afforded 31 mg (93%) of the title compound as a white solid. 1H-NMR (CDCl3; 400 MHz): δ 9.76 (s, 1H), 8.28 (s, 1H), 7.97 (d, 1H, J=8.3 Hz), 7.33 (dd, 1H, J=8.3, 2.0 Hz), 7.21 (s, 1H, J=2.0 Hz), 5.77 (s, 1H), 3.98 (m, 2H), 3.72 (m, 2H), 2.20-2.15 (m, 4H), 1.75-1.66 (m, 4H), 1.56 (s, 3H). Mass spectrum (ESI, m/z): Calcd. for C21H22N4O3, 379.1 (M+H), found 379.1.

Provenance & Evidence