Iodine → Methyl 4-amino-3,6-dichloro-5-iodopicolinate

Temperature

60 °C

Methyl 4-amino-3,6-dichloropicolinate (10.0 g, 45.2 millimoles (mmol)), periodic acid (3.93 g, 17.2 mmol), and iodine (11.44 g, 45.1 mmol) were dissolved in methanol (30 mL) and refluxed at 60° C. for 27 h. The reaction mixture was concentrated, diluted with diethyl ether, and washed twice with saturated aqueous sodium bisulfite. The aqueous layers were extracted once with diethyl ether, and the combined organic layers were dried over anhydrous sodium sulfate. The product was concentrated and purified by flash chromatography (silica gel, 0-50% ethyl acetate/hexanes) to provide the title compound as a pale yellow solid (12.44 g, 35.9 mmol, 79%): mp 130.0-131.5° C.; 1H NMR (400 MHz, CDCl3) δ 5.56 (s, 2H), 3.97 (s, 3H); 13C NMR (101 MHz, CDCl3) δ 163.80, 153.00, 152.75, 145.63, 112.12, 83.91, 53.21; EIMS m/z 346.

1. concentrationThe reaction mixture was concentrated
2. additiondiluted with diethyl ether
3. washwashed twice with saturated aqueous sodium bisulfite
4. extractionThe aqueous layers were extracted once with diethyl ether
5. dry with materialthe combined organic layers were dried over anhydrous sodium sulfate
6. concentrationThe product was concentrated
7. custompurified by flash chromatography (silica gel, 0-50% ethyl acetate/hexanes)

ORD record

ord-78001c445ed240a092fbfd6b97219fc8

Source dataset

uspto-grants-2015_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09006250B2