Tetrahydrofuran → 2-Fluoro-4-chloro-5cyclopentyloxyphenylhydrazine

Temperature

2.5 °C

To a solution of tin (II) chloride monohydrate (200 g, 0.886 mol) dissolved in concentrated hydrochloric acid (200 ml) and THF (200 ml) was added a THF (200 ml) solution of 2-fluoro-4-chloro-5-cyclopentyloxyphenyl-diazonium fluoroborate (31.3 g, 0.094 mol) under cooling at 0 to 5° C. After stirring for 8 hours at that temperature, an aqueous solution (1,000 ml) of potassium hydroxide (160 g) was added thereto. The solid that was formed was separated by filtration, and the filtrate was extracted with ethyl acetate (1,000 ml×3). The extract was washed with a saturated aqueous solution of sodium chloride (1,000 ml), and dried over anhydrous magnesium sulfate. The drying agent was separated by filtration, and the solvent was distilled off under reduced pressure to obtain 2-fluoro-4-chloro-5cyclopentyloxyphenylhydrazine as brown crystals (20.9 g, 85.6% yield).

1. customThe solid that was formed
2. customwas separated by filtration
3. extractionthe filtrate was extracted with ethyl acetate (1,000 ml×3)
4. washThe extract was washed with a saturated aqueous solution of sodium chloride (1,000 ml)
5. dry with materialdried over anhydrous magnesium sulfate
6. customThe drying agent was separated by filtration
7. distillationthe solvent was distilled off under reduced pressure

ORD record

ord-4ab8b71a92be4d498ff145d0edc0c967

Source dataset

uspto-grants-1995_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05464811