2-Naphthoic acid → 2-Naphthylamine

Temperature

160 °C

Polyphosphoric acid (7.5 g) was added to a mixture of 2-naphthoic acid (600 mg, 3.48 mmol) and hydroxylamine hydrochloride (254 mg, 3.66 mmol) at room temperature and heated slowly to 160° C. The reaction mixture was stirred for 90 min and then allowed to cool to ambient temperature and quenched with crushed ice (50 g). The resultant solid was filtered and washed with water (2×20 mL). The combined filtrate and washings were basified with 10% potassium hydroxide solution (100 mL). The precipitated solid was filtered, washed with water (2×25 mL), petroleum ether (2×20 mL), diethyl ether (2×20 mL) and dried in vacuo to afford naphthalen-2-amine (165 mg, 34%) as a light pink solid.

1. temperatureto cool to ambient temperature
2. customquenched with crushed ice (50 g)
3. filtrationThe resultant solid was filtered
4. washwashed with water (2×20 mL)
5. filtrationThe precipitated solid was filtered
6. washwashed with water (2×25 mL), petroleum ether (2×20 mL), diethyl ether (2×20 mL)
7. customdried in vacuo

ORD record

ord-a68b9d12d7c24f3fbe22ab6470e83a44

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08993574B2