HCID 57507746, compound → HCID 70497874, compound

Participants

Reaction Conditions

Reaction Steps

Methyl 4-amino-3-chloro-6-(2,4-dichloro-3-methoxyphenyl)picolinate (Compound C, prepared by the methods described in U.S. Pat. No. 7,314,849 B2; 500 mg, 1.4 mmol) was dissolved in benzyl alcohol (10 mL), treated with titanium(IV) isopropoxide (ca 100 μL) and heated at 85-90° C. After 2 h, another portion of titanium(IV) isopropoxide (100 μL) was added and heating was continued for another 18 h. The volatiles were removed under high vacuum, and the residue was purified by silica gel chromatography (eluting with 5% Et2O-30% dichloromethane (CH2Cl2)-65% hexane). The material was further purified by reverse phase high performance liquid chromatography (RP-HPLC; eluting with 70% acetonitrile) to give the title compound (375 mg, 61%): mp 107-108° C.; 1H NMR (400 MHz, CDCl3) δ 7.50-7.26 (m, 8H), 6.97 (s, 1H), 5.42 (s, 2H), 4.85 (s, 2H), 3.91 (s, 3H); ESIMS m/z 437 ([M+H]+).

Provenance & Evidence