Pyridine → 1-Chlorocarbonyloxy-2,4-dimethoxynaphthalene

Participants

Reaction Conditions

Reaction Steps

To a solution of 1.27 g of 1-hydroxy-2,4-dimethoxynaphthalene, prepared as shown in Preparations 7 and 8, in 50 ml of tetrahydrofuran and 1 ml of pyridine is added 10 ml of a solution of 12.5% phosgene in benzene. The mixture is stirred overnight at 25° C., filtered and the filtrate evaporated under vacuum to afford crude 1-chlorocarbonyloxy-2,4-dimethoxynaphthalene. This chloroformate is dissolved in 50 ml of dry tetrahydrofuran and a solution of 1.14 g of diethylamine in 10 ml of tetrahydrofuran added. After 4 hours at room temperature the reaction mixture is diluted with ethyl acetate and washed with dilute hydrochloric acid. The organic phase is dried over sodium sulfate and solvent removed under reduced pressure to yield 1-diethylcarbamoyloxy-2,4-dimethoxynaphthalene.

Provenance & Evidence