Water → trans-5,6,7,8-Tetrahydro-1,6,7-naphthalenetriol

Beteiligte Stoffe

Reaktionsschritte

A solution of 8.0 g of 5,6,7,8-tetrahydro-6,7-epoxy-1-naphthol in 100 ml of tetrahydrofuran is cooled to 0° C. and 20 ml of water and 0.5 ml of 70% perchloric acid are added. After 4 hours, a further 1.5 ml of acid is added and the solution is stirred for 16 hours at ambient temperature and diluted with 100 ml each of ether, 10% sodium bicarbonate and saturated salt solution. The aqueous layer is separated and washed with 150 ml of 1:1 ether-tetrahydrofuran. The organic phase is washed with saturated salt solution, dried and evaporated to give an oil which solidifies on trituration with chloroform. Recrystallization gives in two crops, 4.85 g of solid which is recrystallized from ethyl acetate to give 3.84 g, melting point 179.5°-181.5° C. Two further recrystallizations of a small sample give the analytical specimen, melting point 183°-184° C.

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