Ammonium Acetate → HCID 86709709, compound

Participants

Reaction Steps

Zinc dust (273 mg, 4.18 mmol) was added to a solution of (S)-1-[(S)-2-((S)-2-tert-butoxycarbonylamino-3-methyl-butyrylamino)-propionyl]-hexahydro-pyridazine-3-carboxylic acid 2,2,2-trichloro-ethyl ester (98 mg, 0.19 mmol) in tetrahydrofuran (15 mL). This suspension was treated with a solution of ammonium acetate (220 mg, 2.85 mmol) in water (5 mL). After stirring at room temperature for 3 h, zinc residues were filtered off and the volatiles were removed in vacuo. The residue was partitioned between ethyl acetate and saturated potassium hydrogen sulfate solution and the volatiles were removed in vacuo. The residual acetic acid was removed by azeotroping with toluene (3×10 mL) to give crude (S)-1-[(S)-2-((S)-2-tert-butoxycarbonylamino-3-methyl-butyrylamino)-propionyl]-hexahydro-pyridazine-3-carboxylic acid which was combined with crude (E)-2,2-dimethyl-4-[2-((R)-1-methylamino-ethyl)-quinolin-7-yl]-but-3-enoic acid methyl ester in anhydrous acetonitrile (10 mL) and N,N-diisopropylethylamine (0.165 mL, 0.95 mmol). This solution was then treated with 2-(1H-7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyl uronium hexafluorophosphate methanaminium (94 mg, 0.25 mmol). After stirring at room temperature for 16 h, the volatiles were removed in vacuo. The residue was dissolved in ethyl acetate, and subsequently washed with saturated ammonium chloride solution and sodium bicarbonate solution. The organics were combined and the volatiles were removed in vacuo. The residue was purified by silica gel chromatography using a 10 g Biotage cartridge eluted with a continuous gradient of iso-hexanes/acetone 1:0 to 1:1 to afford the title compound (90 mg, 68%) as a white solid. 1H NMR (300 MHz, CD3OD) δ 0.82-1.00 (m, 6H), 1.28-1.40 (m, 3H), 1.50-1.55 (m, 15H), 1.69 (d, J=6.9 Hz, 3H), 1.73-2.12 (m, 5H), 2.76-2.92 (m, 5H), 3.74 (s, 3H), 3.84-4.00 (m, 1H), 4.25-4.45 (m, 1H), 5.22-5.40 (m, 1H), 6.25 (q, J=6.9 Hz, 1H), 6.57-6.74 (m, 2H), 7.35-7.48 (m, 1H), 7.69-7.77 (m, 1H), 7.80-7.88 (m, 1H), 7.90-8.00 (m, 2H), 8.18-8.30 (m, 1H). LCMS (m/z) 695.4 [M+H], Tr=3.00 min.

Provenance & Evidence