Hydrazine hydrate (1:1) → HCID 67339970, compound

Temperature

80 °C

A stirred mixture of tert-butyl 4-(6-chloropyridazin-3-yl)-5,6-dihydropyridine-1(2H)-carboxylate (870 mg, 2.94 mmol) and hydrazine hydrate (4.29 mL, 88.25 mmol) in acetonitrile (15 mL) was heated at 80° C. for 4 hours. The mixture was partially evaporated (removing MeCN) and diluted with water (10 mL). The reaction mixture was extracted with DCM (3×50 mL). The organic layer was dried over Na2SO4, filtered and evaporated to afford crude product as a gum, which crystallised on trituration with ether. The precipitate was collected by filtration, washed with ether and dried under vacuum to afford tert-butyl 4-(6-hydrazinylpyridazin-3-yl)-5,6-dihydropyridine-1(2H)-carboxylate (503 mg, 58.7%) as a cream crystalline solid.

1. customThe mixture was partially evaporated
2. custom(removing MeCN)
3. additiondiluted with water (10 mL)
4. extractionThe reaction mixture was extracted with DCM (3×50 mL)
5. dry with materialThe organic layer was dried over Na2SO4
6. filtrationfiltered
7. customevaporated
8. customto afford crude product as a gum, which
9. customcrystallised on trituration with ether
10. filtrationThe precipitate was collected by filtration
11. washwashed with ether
12. customdried under vacuum

ORD record

ord-28de808114b941c6bddddf35788c72c3

Source dataset

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08003649B2