Trifluoroacetic acid → 4-[2,6-Bis-(4-cyanophenoxy)pyridine-3-carbonyl]piperazine

Participants

Reaction Conditions

Reaction Steps

4-[2,6-Bis-(4-cyano-phenoxy)pyridine-3-carbonyl]-piperazine-1-carboxylic acid tert-butyl ester 1.2 g (2.28 mmol) was dissolved in 5 ml of DCM at 5° C. under inert atmosphere. 0.7 ml of TFA was added over a 10 min period, while the temperature was maintained at 5° C. Stirring was continued for 1 h at RT and reaction progress was monitored by TLC. The reaction mixture was concentrated under reduced pressure and the residual crude product was purified by column chromatography using chloroform: ethylacetate (8:2) as eluant to afford 0.9 g of the required product. Percentage purity (LCMS): 88.2%, (M+1): 425.1. 1H NMR (DMSO-d6): δ 3.15 (2H, m), 3.22 (2H, m), 3.64 (2H, m), 3.85 (2H, m), 7.00 (1H, d), 7.34 (4H, t), 7.82 (4H, t), 8.08 (1H, d), 9.02 (1H, brs).

Provenance & Evidence