Synthesis of Terpyridines: Simple Reactions—What Could Possibly Go Wrong?

Abstract

The preparation of 24-functionalized 12,22:26,32-terpyridines (4′-functionalized 3,2:6′,3″-terpyridines) by the reaction of three 4-alkoxybenzaldehydes with 3-acetylpyridine and ammonia was investigated; under identical reaction conditions, two (R =nC4H9, C2H5) gave the expected products whereas a third (R = nC3H7) gave only a cyclohexanol derivative derived from the condensation of three molecules of 3-acetylpyridine with two of 4-(n-propoxy)benzaldehyde. A comprehensive survey of “unexpected” products from reactions of ArCOCH3 derivatives with aromatic aldehydes is presented. Three different types of alternative product are identified.

Keywords

• terpyridines
• 3,2′:6′,3″-terpyridine
• cyclohexanol derivative
• condensation
• heterocyclic