反应详情

190.8 g (0.541 mole) of methyl 2-[4-(5-chloro-3-nitropyridin-2-yloxy)phenoxy]propionate are dissolved in 1.9 l of dioxan. 40 g of Raney nickel catalyst are added and hydrogenation is effected with hydrogen at 20°-25° C. The catalyst is then removed by filtration, the solvent is distilled off and the still warm oily residue is crystallised by stirring it in hexane. The crystalline precipitate is isolated by filtration and dried, affording 167.4 (96% of theory) of methyl 2-[4-(3-amino-5-chloropyridin-2-yloxy)phenoxy]propionate with a melting point of 92°-94° C.

1. customThe catalyst is then removed by filtration
2. distillationthe solvent is distilled off
3. customthe still warm oily residue is crystallised
4. customThe crystalline precipitate is isolated by filtration
5. customdried