4-{3-[7-(2-Cyano-2,2-dimethyl-acetyl)-5H-pyrrolo[2,3-b]pyrazin-2-yl]-phenyl}-piperazine-1-carboxylic acid tert-butyl ester → 2,2-Dimethyl-3-oxo-3-[2-(3-piperazin-1-yl-phenyl)-5H-pyrrolo[2,3-b]pyrazin-7-yl]-propionitrile

Participants

Reaction Steps

A solution of 4-{3-[7-(2-Cyano-2,2-dimethyl-acetyl)-5H-pyrrolo[2,3-b]pyrazin-2-yl]-phenyl}-piperazine-1-carboxylic acid tert-butyl ester from step 1 in hexafluoroisopropanol was heated at 150° C. in a microwave oven for 45 min. The reaction mixture was cooled to room temperature and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel with a mixture of 28% aqueous ammonium hydroxide:methanol:DCM (1:10:60) in DCM (20% to 80% gradient over 30 min) to give 39 mg of the desired product as a yellow powder. 1H NMR (CDCl3, 400 MHz): δ 8.81 (s, 1H), 8.50 (s, 1H), 7.91 (s, 1H), 7.60-7.54 (m, 1H), 7.42 (t, J=7.9 Hz, 1H), 7.08-7.04 (m, 1H), 3.35 (t, J=4 Hz, 2H), 3.14 (t, J=4 Hz, 2H), 1.92 (s, 6H); MS [M+H]+: 375.

Provenance & Evidence