Trifluoroacetic anhydride → 5-(2-benzyl-2H-indazol-6-yl)-7-{1-[(dimethylamino)acetyl]-1,4,5,6-tetrahydropyridin-3-yl]pyrrolo[2,1-f][1,2,4]triazin-4-amine

Participants

Reaction Steps

To a cooled (0° C.) mixture of 3-[4-amino-5-(2-benzyl-2H-indazol-6-yl)pyrrolo[2,1-f][1,2,4]triazin-7-yl]-1-(N,N-dimethylglycyl)piperidin-3-ol (58 mg, 0.11 mmol) and N,N-diisopropylethylamine (58 μL, 0.33 mmol) in CH2Cl2 (2 mL) was added trifluoroacetic anhydride (31 μL, 0.22 mmol), dropwise. The ice bath was removed and the mixture was stirred at rt for 2 h. The reaction was cooled (0° C.) and additional N,N-diisopropylethylamine (58 μL) and trifluoroacetic anhydride (31 μL) was added. The ice bath was removed and the reaction was stirred at rt for 5 h. Water (5 mL) was added and the layers were separated. The aqueous phase was extracted with CH2Cl2 (2×5 mL) and the combined organic layers were washed with brine, dried (Na2SO4) and concentrated. To a solution of the residue in EtOH (3 mL) was added NaOH (66 mg, 1.66 mmol). The mixture was stirred at rt for 17 h. The mixture was partitioned between EtOAc (10 mL) and H2O (10 mL). The layers were separated and the organic phase was washed with H2O (10 mL), brine, dried (Na2SO4) and concentrated. The material was crystallized from EtOAc/hexanes to afford 41 mg (73%) of the desired product. 1H NMR (400 MHz, DMSO-d6) δ 8.66-8.70 (m, 1H,) 8.55 (s, 1 H), 7.94-7.98 (m, 1 H), 7.81 (d, 1 H), 7.61 (s, 1 H), 7.27-7.36 (m, 5 H), 7.15 (dd, 1 H), 6.76-6.80 (m, 1 H), 5.65 (s, 2 H), 3.56-3.79 (m, 2 H), 3.22-3.28 (m, 2 H), 2.48-2.59 (m, 2 H), 2.17-2.25 (m, 6 H), 1.85-1.94 (m, 2 H); ES-MS m/z 507.13 [M+H]+, HPLC RT (min) 2.31.

Provenance & Evidence