Quinoline alkaloids. Part XI. A study of the Claisen rearrangement of the 3,3-dimethylallyl ether of 4-hydroxy-1-methyl-2-quinolone. Synthesis of ifflaiamine and the identification of a new alkaloid from Flindersia ifflaiana F. Muell

Abstract

Claisen rearrangement of 1-methyl-4-(3-methylbut-2-enyloxy)2-quinolone resulted mainly in abnormal reaction to give a 1,2-dimethylallylquinoline and its linear and angular cyclisation products. The intermediate 1,1-dimethylallylquinoline was trapped as its acetate which was cyclised to ifflaiamine with hydrobromic acid. An isomeric furanoquinoline alkaloid is shown to occur with ifflaiamine in Flindersia ifflaiana and the biogenesis of the two alkaloids is discussed.