Triphenylphosphine Oxide → HCID 135985850, compound

Participants

Reaction Conditions

Reaction Steps

Triflic anhydride (82 μL, 0.485 mmol) was added dropwise at 0° C. under nitrogen to a solution of triphenylphosphine oxide (135 mg, 0.485 mmol) in DCM (1.5 mL) and the mixture was stirred at 0° C. for 20 minutes. The resulting solution was then added dropwise at 0° C. under nitrogen to a stirred suspension of N-(2-aminophenyl)-4-oxo-3-(prop-2-ynyl)-3,4-dihydroimidazo[5,1-d][1,2,3,5]tetrazine-8-carboxamide (50 mg, 0.162 mmol) in DCM (1.5 mL). The resulting dark brown mixture was stirred for 3 days and the precipitate, which formed during the reaction, was filtered. The solid was dissolved in MeCN:MeOH and triethylamine (75 μL) was added. The mixture was stirred for about 5 minutes and was then concentrated under vacuum. The crude product was suspended in ethyl acetate and the resulting suspension was filtered. The solid was washed with ethyl acetate to give the pure title compound as a bright yellow solid (22 mg, 47%). (Less triethylamine (100 μL/250 mg starting material) was used during the neutralization on larger scale preparations.) δH (DMSO d6): 13.1 (1H, s), 9.02 (1H, s), 7.73-7.75 (1H, m), 7.56-7.58 (1H, m), 7.22-7.27 (2H, m), 5.15 (2H, d, J=2.5), 3.53 (1H, t, J=2.5).

Provenance & Evidence