Ethanol → HCID 2812134, compound

4-Fluorophenylhydrazine hydrochloride (1.63 g, 10.0 mmol) was mixed with ethanol (150 mL) and pyridine (2.43 mL, 30.0 mmol, 3.0 eq.). The mixture was heated to reflux, and more pyridine (2.43 mL, 30.0 mmol, 3.0 eq.) was added. After stirring for 5 minutes at room temperature, thiophenecarbonyl chloride (10.8 mL, 1.47 g, 10.0 mmol, 1.0 eq.) was added. The suspension was stirred for 2 hours at room temperature, and then at reflux temperature for 30 minutes under a nitrogen atmosphere. Water (375 mL) was added, and the mixture was extracted with ethyl acetate (2×300 mL). The combined organic layers were then washed with brine (100 mL), dried over magnesium sulfate, filtered, and concentrated in vacuo to yield the crude product (2.3 g) as a brown solid. Purification using ISCO flash chromatography (silica, gradient heptanes/ethyl acetate) gave N′-(4-fluorophenyl)thiophene-2-carbohydrazide (575 mg, 2.43 mmol, yield 24.3%) as a brown solid.

1. temperatureThe mixture was heated
2. temperatureto reflux
3. stirringThe suspension was stirred for 2 hours at room temperature
4. temperatureat reflux temperature for 30 minutes under a nitrogen atmosphere
5. extractionthe mixture was extracted with ethyl acetate (2×300 mL)
6. washThe combined organic layers were then washed with brine (100 mL)
7. dry with materialdried over magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customto yield the crude product (2.3 g) as a brown solid
11. customPurification

ORD record

ord-4630505dd1554fd3a01f49bbdf88547b

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09051309B2