synthesis and spectroscopic characterization of novel amics and cyclic imides derivatives of bisphosphonic acid

This study presents the synthesis and spectroscopic characterization of new amic and imide derivatives incorporating bis (phosphonic acid) moieties. the key starting material, [(4-aminophenyl) (hydroxyl)methylene] bis (phosphonic acid) (1), was reacted with various cyclic anhydrides-succinic, maleic, 1,8-naphthalic, 3-nitrophthalic, glutaric, cis-1,3,4,6-tetrahydrophthalic, and pyromellitic dianhydride (2)-to yield the corresponding amic acids (3a–3f and 5g). these amic acids were subsequently dehydrated using acetic anhydride in the presence of anhydrous sodium acetate under reflux, producing novel imide derivatives (4a–4f and 6g). the synthesized compounds were characterized through various physical and spectroscopic techniques, including fourier-transform infrared spectroscopy (ft-ir), nuclear magnetic resonance spectroscopy (1h, 13c and 31p nmr).