Hydrochloric Acid → 4-Fluorobenzamidine

To a solution of hexamethyldisilazane (19.4 g, 120 mmol) in diethyl ether (200 ml) was added dropwise a 1.6 N solution (75.0 ml, 120 mmol) of n-butyllithium in hexane under ice-cooling. Thereto 4-fluorobenzonitrile (7.01 g, 57.9 mmol) was added, followed by stirring at room temperature for 2 hours. Thereto 3 N hydrochloric acid (80 ml) was added dropwise under ice-cooling, and the reaction mixture was stirred under ice-cooling for 0.5 hour. Water (200 ml) was added thereto, and the diethyl ether layer was removed. The aqueous layer was basified with an aqueous 3 N sodium hydroxide solution, and then extracted with chloroform. The extracts were dried over anhydrous magnesium sulfate and the solvent was distilled off under reduced pressure to give 4.90 g (61.3%) of the desired product as a solid.

1. temperaturecooling
2. temperaturecooling
3. stirringthe reaction mixture was stirred under ice-
4. temperaturecooling for 0.5 hour
5. customthe diethyl ether layer was removed
6. extractionextracted with chloroform
7. dry with materialThe extracts were dried over anhydrous magnesium sulfate
8. distillationthe solvent was distilled off under reduced pressure

ORD record

ord-45359da57b2f443c9d7f7e4af9bcee0b

Source dataset

uspto-grants-2010_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07851473B2