Acetate → 6-Chloro-3-isothiocyanato-4-methylpyridazine

To a solution of 6-chloro-4-methylpyridazin-3-amine (2.86 g, 20.0 mmol) in aqueous sodium bicarbonate (10 mL) and tetrahydrofuran (40 mL) was added thiophosgene (1.69 mL, 22.0 mmol) dropwise at 0° C. After stirring for 1 hr, water and ethyl, acetate were added to the mixture and the insoluble materials were filtered off. The filtrate was washed with brine, dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was purified by flash chromatography on silica gel eluting with a 10-50% ethyl acetate/n-hexane gradient mixture. The filtrate was concentrated in vacuo to give the title compound (304 mg, 1.64 mmol, 8%) as a pale yellow solid.

1. filtrationthe insoluble materials were filtered off
2. washThe filtrate was washed with brine
3. dry with materialdried over anhydrous sodium sulfate
4. concentrationconcentrated in vacuo
5. customThe residue was purified by flash chromatography on silica gel eluting with a 10-50% ethyl acetate/n-hexane gradient mixture
6. concentrationThe filtrate was concentrated in vacuo

ORD record

ord-a40b56ffdda44bd18a95220245db8f7f

Source dataset

uspto-grants-2014_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08901141B2