Water → HCID 18968903, compound

Participants

Reaction Conditions

Reaction Steps

A solution of methanesulfonic acid (25 ml) and phosphorus pentaoxide (5.2 g, 37 mmol) was heated at 90° C. for 3.5 h. The solution was cooled to 50° C. and 3,4-dihydro-2H-phenanthren-1-one-oxime (4.8 g, 23 mmol) was added. The solution was heated at 60° C. for 10 minutes and then at 80° C. for 3.5 hr. The hot reaction mixture was added to a mixture of ice (300 g) and water (100 ml). The precipitated solid was isolated by filtration, redissolved in dichloromethane (50 ml), dried (MgSO4) and evaporated in vacuo to afford a white product. Purification was achieved using column chromatography with silica gel (200 g) and a mixture of heptane and ethyl acetate (1:2) to afford 4.8 g of 4-oxo-2,3,4,5-tetrahydro-1H-naphtho[2,1-b]azepine.

Provenance & Evidence