Reacción #1010860

Ecuación de reacción

Methyl 4-amino-3,6-dichloropicolinate

periodic acid

iodine

→

title compound

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

Disolventes

methanol

Condiciones de reacción

Tratamiento posterior

1. 1
   ConcentraciónThe reaction mixture was concentrated
2. 2
   workup.ADDITIONdiluted with diethyl ether
3. 3
   Lavadowashed twice with saturated aqueous sodium bisulfite
4. 4
   ExtracciónThe aqueous layers were extracted once with diethyl ether
5. 5
   Secadothe combined organic layers were dried over anhydrous sodium sulfate
6. 6
   ConcentraciónThe product was concentrated
7. 7
   Otropurified by flash chromatography (silica gel, 0-50% ethyl acetate/hexanes)

Procedimiento

Methyl 4-amino-3,6-dichloropicolinate (10.0 g, 45.2 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.

Fuente