Synthesis of new N-phenyl-N-(1-phenylhex- 5-en-1-yl)acetamides and their ¹H-NMR conformational study

Antifungal and antiparasitic activities for N-acetyl derivatives of different N-(prop)butenylamines have been previously evaluated and reported. Consequently, an efficient and versatile synthesis procedure and complete characterization of different N-phenyl-N-(1-phenylhex-5-en-1-yl)acetamides is presented. Two conformational isomers were observed for one of the compounds in their ¹H/¹³C-NMR spectra. The conformational analysis was carried out using the B3LYP functional with the 6-31+G(2d,p) basis and the NMR spectroscopic data. The dihedral angle values of the allylic system obtained by both computational methods and ¹H-NMR data analysis (Garbisch's equation) were compared and used to successfully determine the conformational structures and the intramolecular interaction responsible for signal duplicity and chemical shifting respectively.