Trifluoroacetic acid → 6-benzyl-1-methyl-6H-pyrrolo[2,3-e][1,2,4]triazolo[4,3-a]pyridine-7-carboxylic acid trifluoroacetate

Participants

Reaction Steps

The mixture from Step 3 containing 1-methyl-6H-pyrrolo[2,3-e][1,2,4]triazolo[4,3-a]pyridine-7-carboxylic acid (0.298 g, 1.38 mmol) was mixed in DMF (6 mL) and acetonitrile (6 mL) and was treated with Cs2CO3 (1.8 g, 5.5 mmol) and was stirred for 10 minutes before the addition of benzyl bromide (0.30 mL, 2.5 mmol, Aldrich). The reaction was stirred overnight. Water was added and the product was extracted with three portions of EtOAc. The combined extracts were dried over sodium sulfate, filtered and concentrated. Flash chromatography, eluting with a gradient from 0-10% MeOH in DCM, was used to purify the desired alkylated ester (265 mg). This was stirred with 1.0 M NaOH (10 mL, 10 mmol) and methanol (10 mL) overnight. Some TFA was used to aid in dissolving insolubles and the product was purified via preparative HPLC-MS (C18 eluting with a gradient of MeCN and H2O containing 0.1% TFA). Yield: (44 mg, 7%). LCMS (M+H)+: 307.0.

Provenance & Evidence