2-Chloro-p-toluidine → 227958-97-6

Temperature

-5 °C

A suspension of 2-chloro-4-methyl aniline (10.1 mL, 11.63 g, 82.1 mmol) in 64 mL water and 60 mL 12 N HCl was cooled to −5° C. (internal temperature) and stirred with a mechanical stirrer. A solution of sodium nitrite (8.26 g, 119.7 mmol) in 56 mL water was added over 30 minutes. The solution became more clear but some solid remained. The mixture was stirred at −5° C. for 20 minutes and then cooled to −10° C. A solution of tin(II) chloride dihydrate (53.60 g, 237.6 mmol) in 36 mL 12 N HCl was added dropwise over 30 minutes while maintaining an internal temperature of −5 to −10° C. The resulting pinkish-brown mixture was stirred at −5 to −10° C. for 2 hours and then filtered cold through a pre-chilled fritted glass funnel. The collected solids were washed with cold 1% ethanol in ether (100 mL) followed by cold ether (500 mL) and air dried for 30 minutes. After drying in vacuo, the desired product was obtained as a very pale yellow crystalline solid (7.76 g, 49%). 1H NMR δ (300 MHz, CDCl3) δ 10.09 (bs, 2 H), 7.89 (s, 1 H), 7.25 (d, 1 H, Jm=1.2 Hz), 7.13 (dd, 1 H, Jo=8.4 Hz, Jm=1.2 Hz), 7.02 (d, 1 H, Jo=8.4 Hz), 2.24 (s, 3 H); MS (CI) m/z 157/159.

1. stirringThe mixture was stirred at −5° C. for 20 minutes
2. temperaturecooled to −10° C
3. temperaturewhile maintaining an internal temperature of −5 to −10° C
4. stirringThe resulting pinkish-brown mixture was stirred at −5 to −10° C. for 2 hours
5. filtrationfiltered cold through a pre-chilled fritted glass funnel
6. washThe collected solids were washed with cold 1% ethanol in ether (100 mL)
7. customdried for 30 minutes
8. customAfter drying in vacuo

ORD record

ord-a50d9ff6e9ac4d0f8b78614c534f61c8

Source dataset

uspto-grants-2004_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06787547B2