Trimethylsilyldiazomethane → Ethyl 6-(3-chloro-4-fluorobenzyl)-4-methoxy-5-oxo-5,6,7,8-tetrahydro-2,6-naphthyridine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of ethyl 6-(3-chloro-4-fluorobenzyl)-4-hydroxy-5-oxo-5,6,7,8-tetrahydro-2,6-naphthyridine-1-carboxylate (208 g, 0.55 mol) in a mixture of dichloromethane (830 mL) and methanol (410 mL) at 10° C., a solution of (trimethyl-silyl)diazomethane (600 mL, 1.2 mol; 2M) in hexanes was added over a period of 1 hour with the reaction temperature maintained below 15° C. The reaction mixture (unstirred) was allowed to stand at 10° C. overnight, and then at 20° C. for additional 4 hours. The reaction mixture was cooled back to 10° C. and quenched with acetic acid (˜75 mL). The product mixture was concentrated under vacuum and the residue recrystallized from boiling methyl tert-butyl ether and heptane. The solid recrystallized was collected by filtration, washed with a mixture of methyl tert-butyl ether and heptane (1:1, v/v), and air dried to afford the title compound.

Provenance & Evidence