Facile synthesis of novel 3-substituted pyrido[1,2-a]pyrimidinium salts using vinamidinium salts

A facile and efficient route to one-pot synthesis of new cyclophanes using vinamidinium salts

“…As shown in Scheme 3, the procedure is done in two-step: (i) synthesis of the 2-substituted vinamidinium salts (2a-g) by the Vilsmeier-Arnold formylation of the substituted acetic acids (1a-g) as explained in authors previous work; [67][68][69][70][71][72][73][74][75][76] and (ii) synthesis of cyclophane derivatives (5a-f, 6a-g) by the reaction of 2-substituted vinamidinium salts (2a-g) with 1,4- 4) in reuxing acetonitrile in the presence of acetic acid for 15 h to manage the cyclophane derivatives (5a-f, 6ag). To provide the best reaction conditions in second step, the reaction of vinamidinium salt 2f with 1,4-phenylenedimethanamine (3) was chosen as model reaction and the impacts of solvents and catalysts were investigated.…”

“…They can easily undergo condensation reaction with bifunctional nucleophiles to form heterocycles. During past years, our group has been investigated the utilization of vinamidinium salts for the synthesis of heterocyclic compounds [67][68][69][70][71][72][73][74][75][76] (Scheme 2).…”