5-Aminosalicylic Acid → Fendosal

Participants

Reaction Steps

A mixture of 1.92 g of 5-aminosalicylic acid and 5.0 g of tautomeric 1-[3,4-dihydro-1-(2-oxo-2-phenylethyl)-2(1H)-naphthalenylidene]pyrrolidinium bromide in equilibrium with 1-phenacyl-2-(1-pyrrolidino)-3,4-dihydronaphthalene hydrobromide (Example 1a), in 75 ml of methanol is refluxed under nitrogen for 9 hours. The solution is allowed to reach ambient temperature before being filtered. The methanol is removed under a vacuum to give a viscous oil which is dissolved in acetonitrile. This solution immediately crystallizes to give a yellow crystalline solid which is collected by filtration and washed with acetonitrile to give 3-(3-carboxy-4-hydroxyphenyl)-4,5-dihydro-2-phenylbenz[e]indole.

Provenance & Evidence