Pyrylium-mediated transformations of natural products. Part 2. Reaction of 4-(4-methoxy-3-sulphophenyl)-2,6-bis-(4-sulphophenyl)pyrylium perchlorate with primary amines

Abstract
The title pyrylium cation reacts with amines in aqueous solution to give mixtures of divinylogous amide and pseudobase. The two products are formed by kinetic control in quantities which then slowly come to equilibrium. Further pyridinium ion is formed slowly from pseudobase. The divinylogous amide cyclises to pyridinium ion. Kinetic rate constants are described for reactions with lysine and other typical primary amines. With s-butylamine appreciable quantities of the 2H-pyran are formed.

This publication has 0 references indexed in Scilit: