Triethylamine → 3-Cyanobenzohydrazide

Temperature

0 °C

A solution of 3-cyanobenzoic acid (1.0 g, 6.80 mmol) in tetrahydrofuran (10 mL) at 0° C. was treated with triethylamine (2.84 mL, 20.4 mmol) and ethyl chloroformate (0.78 mL, 8.16 mmol) and stirred at 0° C. for 1 h. The resulting white precipitate was removed by filtration and the filtrate cooled back to 0° C. Hydrazine monohydrate (1.00 mL, 20.4 mmol) was added and the mixture stirred at ambient temperature for 3.5 hours. The reaction mixture was then concentrated to dryness in vacuo and the residue was dissolved in dichloromethane (150 mL). The organic phase was sequentially washed with water (100 mL), 1 N sodium hydroxide (100 mL), water (100 mL) and brine (100 mL). The organic phase was dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. Silica gel chromatography using 3% methanol in dichloromethane afforded 0.32 g (30%) of 3-cyanobenzhydrazide.

1. customThe resulting white precipitate was removed by filtration
2. temperaturethe filtrate cooled back to 0° C
3. stirringthe mixture stirred at ambient temperature for 3.5 hours
4. concentrationThe reaction mixture was then concentrated to dryness in vacuo
5. dissolutionthe residue was dissolved in dichloromethane (150 mL)
6. washThe organic phase was sequentially washed with water (100 mL), 1 N sodium hydroxide (100 mL), water (100 mL) and brine (100 mL)
7. dry with materialThe organic phase was dried over anhydrous sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated in vacuo

ORD record

ord-77a9e7bdef0b4026aa1b55d396016c80

Source dataset

uspto-grants-2006_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07112595B2