Formic Acid → 6-chloro-5-pyrrolidin-1-yl-1H-benzoimidazole

Temperature

130 °C

Formic acid (2.9 mL) was added to a mixture of 4-chloro-2-nitro-5-pyrrolidin-1-yl-phenylamine (0.240 g, 1.00 mmol) and SnCl2.H2O (0.680 g, 3.00 mmol), and the mixture was heated to 130° C. in a microwave reactor for 5 min. Six reactions were performed on the same scale. The combined crude mixture was filtered and washed with EtOAc (100 mL). The organic layer was treated with water (25 mL) and neutralized with aqueous 6M NaOH. The aqueous layer was extracted with EtOAc (3×30 mL). The combined organic layers were washed with brine (50 mL), dried, filtered, and concentrated under reduced pressure. The residue was triturated with EtOAc and the solid was collected to yield the titled compound (1.08 g, 70%) as the formate salt. MS (ESI/CI): mass calcd. for C11H12ClN3, 221.1; m/z found, 222.1 [M+H]+. 1H NMR (400 MHz, DMSO-d6): 12.84-12.16 (br s, 1H), 8.13 (s, 1H), 8.11 (s, 1H), 7.59 (s, 1H), 7.20 (s, 1H), 3.20 (t, J=6.3 Hz, 4H), 2.06-1.66 (m, 4H).

1. filtrationwas filtered
2. washwashed with EtOAc (100 mL)
3. additionThe organic layer was treated with water (25 mL)
4. extractionThe aqueous layer was extracted with EtOAc (3×30 mL)
5. washThe combined organic layers were washed with brine (50 mL)
6. customdried
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customThe residue was triturated with EtOAc
10. customthe solid was collected

ORD record

ord-6527be80a611453c8b9449ac1690f571

Source dataset

uspto-grants-2014_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08759345B2