Infrared, 1H and 13C NMR spectra, structural charcterization and DFT calculations of novel adenine-cyclodiphosp(V)azane derivatives

► Novel adenine chlorocyclodiphosph(V)azanes (IIIa-c) have synthesized and characterized. ► One mole of phosp(V)azane reacts with two moles adenine (II) adducts to yield IIIa-c. ► 1H and 13C NMR spectral interpretations favor the Ci geometries of compounds IIIa-c. ► Geometries have been optimized using B3LYP method with 3-21G(d) basis set. ► Complete vibrational assignments were proposed for compounds IIIa-c.