Sodium borohydride → 10-Methyl-8,9,10,11-tetrahydropyridazino[1',6':1,2]imidazo[4,5-c]quinoline

A solution of 10-methyl-8,9-dihydropyridazino[1′,6′:1,2]imidazo[4,5-c]quinoline (1.96 g, 8.30 mmol) in methanol (50 mL) was cooled to 0° C. The solution was treated with NaBH4 (1.26 g, 33.2 mmol) over 3 min. The reaction was allowed to come to ambient temperature over 3 h. The reaction was quenched with slow addition of saturated NH4Cl aqueous solution (20 mL) and then concentrated under reduced pressure to remove the methanol. The residual material was partitioned between chloroform (75 mL) and 10% Na2CO3 aqueous solution (25 mL) and then separated. The organic portion was washed with water (25 mL) and brine (25 mL), dried over Na2SO4, filtered, and concentrated under reduced pressure to give a tan solid. Purification by column chromatography (100 g silica gel eluted with 95:5 chloroform:methanol) yielded 1.56 g of 10-methyl-8,9,10,11-tetrahydropyridazino[1′,6′:1,2]imidazo[4,5-c]quinoline as a tan solid.

1. customThe reaction was quenched with slow addition of saturated NH4Cl aqueous solution (20 mL)
2. concentrationconcentrated under reduced pressure
3. customto remove the methanol
4. customThe residual material was partitioned between chloroform (75 mL) and 10% Na2CO3 aqueous solution (25 mL)
5. customseparated
6. washThe organic portion was washed with water (25 mL) and brine (25 mL)
7. dry with materialdried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customto give a tan solid
11. customPurification
12. washby column chromatography (100 g silica gel eluted with 95:5 chloroform:methanol)

ORD record

ord-b986e19de594415794b48c99affbc291

Source dataset

uspto-grants-2012_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08088788B2