Hydrochloric Acid → 1,7-Dimethyl-4-nitro-6H-pyrrolo[2,3-e][1,2,4]triazolo[4,3-a]pyridine

To a solution of 1,7-dimethyl-6-(phenylsulfonyl)-6H-pyrrolo[2,3-e][1,2,4]triazolo[4,3-a]pyridine (1.0 g, 3.1 mmol, from Example 228, Step 4) in 1,2-dichloroethane (20 mL) was added nitronium tetrafluoroborate (0.57 g, 4.3 mmol, Aldrich). The reaction mixture was stirred overnight, filtered and washed with DCE, and air-dried overnight. To a suspension of the nitrated product in Methanol (7 mL) was added 10% (w/w) KOH in water (7 mL, 10 mmol) and the reaction mixture was stirred for 3 hours, after which time the reaction mixture was diluted with DCM and water. 2.0 M solution of HCl in water (4.0 mL, 8.0 mmol) was added to adjust pH 10 and the mixture was stirred for 2 hours. The precipitated solid was isolated by filtration, washed with DCM and water, and then dried at 50° C. under high vacuum for 2 hours. Yield: (0.30 g, 40%).

1. filtrationfiltered
2. washwashed with DCE
3. customair-dried overnight
4. additionTo a suspension of the nitrated product in Methanol (7 mL)
5. stirringthe reaction mixture was stirred for 3 hours
6. stirringthe mixture was stirred for 2 hours
7. customThe precipitated solid was isolated by filtration
8. washwashed with DCM and water
9. customdried at 50° C. under high vacuum for 2 hours

ORD record

ord-f200a82f6c704d3cab366422258aed6b

Source dataset

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09309246B2