Hydrazine hydrate (1:1) → HCID 90092588, compound

To a stirred slurry of 4,4-dimethoxy-1-(1,3-thiazol-2-yl)butane-1,3-dione (8a) (1.55 g, 6.76 mmol) in ethanol (63 mL) was added dropwise hydrazine monohydrate (0.38 mL, 7.77 mmol). The mixture was stirred at room temperature overnight, then concentrated in vacuo. A saturated solution of sodium hydrogenocarbonate (8 mL) was added to the residue and the aqueous layer was extracted with ethyl acetate (2×10 mL). The organic layer was dried over sodium sulfate and concentrated in vacuo. The resulting solid was triturated in diethyl ether and the precipitate was filtrated. The filtrate was concentrated and the treatment was repeated as much as necessary. The combined precipitates were dried in vacuo to provide 2-[5-(dimethoxymethyl)-1H-pyrazol-3-yl]-1,3-thiazole (8b) (714 mg, 3.17 mmol, 47%) which was used without further purification.

1. concentrationconcentrated in vacuo
2. additionA saturated solution of sodium hydrogenocarbonate (8 mL) was added to the residue
3. extractionthe aqueous layer was extracted with ethyl acetate (2×10 mL)
4. dry with materialThe organic layer was dried over sodium sulfate
5. concentrationconcentrated in vacuo
6. customThe resulting solid was triturated in diethyl ether
7. filtrationthe precipitate was filtrated
8. concentrationThe filtrate was concentrated
9. customThe combined precipitates
10. customwere dried in vacuo

ORD record

ord-cfe985e7caca402eb5a0859922f843ee

Source dataset

uspto-grants-2016_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09260395B2