methyl 2-(4-amino-2,6-dichlorophenyl)acetate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A suspension of (2,6-dichloro-4-nitro-phenyl)-acetic acid methyl ester (12.7 g, 47.13 mmol) and Raney Nickel (3 g) in MeOH (500 mL) is stirred for 3.5 h at rt, under a hydrogen atmosphere. The reaction mixture is filtered through a pad of celite and concentrated to afford the title compound as a yellow solid: ESI-MS: 232.0/234.0 [M-H]−; tR=3.11 min (System 2). The reaction mixture is filtered through a pad of celite concentrated

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 2-chloro-3-nitro-pyridine (5.0 g, 31.4 mmol), (4-amino-2,6-dichloro-phenyl)-acetic acid methyl ester (7.8 g 33.3 mmol), and a 4 N solution of HCl in dioxane (12 mL, 48.0 mmol, 2.9 equiv) in MeOH/dioxane (60 mL; 1:1, v/v) is stirred for 46.5 h at 100° C. The reaction mixture is allowed to cool to rt and concentrated in vacuo. The residue is dissolved in EtOAc, washed with a saturated aqueous solution of NaHCO3, dried (Na2SO4), filtered and concentrated. Purification of the crude product by silica gel column chromatography (Hexane/EtOAc, 4:1), followed by trituration in diethyl ether, provides the title compound: ES-MS: 355.9/357.9 [M+H]+; tR=5.33 min (System 1); Rf=0.25 (Hexane/EtOAc, 4:1). to cool to rt concentrated in vacuo The residue is dissolved in EtOAc washed with a saturated aqueous solution of NaHCO3 dried (Na2SO4) filtered concentrated Purification of the crude product by silica gel column chromatography (Hexane/EtOAc, 4:1)