Sulfuric Acid → HCID 66668753, compound

Participants

Reaction Steps

To a solution of 4-[(−)-3-(2-methyl-pyridin-4-yl)-3-oxo-1-o-tolyl-propyl]-benzoic acid (80 mg; example 272, step 2) and diisopropylethylamine (0.078 mL) in N,N-dimethylformamide (2.6 mL) was added O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (102 mg) and the reaction mixture stirred at room temperature. After 5 min, acetic acid hydrazide (35 mg; CAS RN 1068-57-1) was added and the reaction mixture heated by microwave irradiation to 100° C. for 10 min. To the reaction mixture was added conc. sulfuric acid (0.24 mL; strongly exothermic!) and heating by microwave irradiation at 140° C. continued for another 10 min. The reaction mixture was extracted over a sat. solution of sodium hydrogencarbonate (50 mL) with ethyl acetate (3×50 mL) and the combined organic phases dried over sodium sulfate. The crude reaction product was purified by silica gel chromatography using a MPLC system (CombiFlash Companion, Isco Inc.) eluting with a gradient of n-heptane/ethyl acetate (100:0 to 50:50) to give the title compound as a light red oil. MS (ESI+): m/z=398.1 ([M+H]+).

Provenance & Evidence