A new diamidophosphoester, (4-CH3-C6H4O)((CH3)2CHNH)2P(O), was synthesized from the reaction of freshly prepared (4-CH3-C6H4O)Cl2P(O) reagent and isopropylamine (1:4 mole ratio) in dry CH3CN. The prepared compound was characterized by IR, 1H-NMR, 13C{1H}-NMR and 31P{1H}-NMR spectroscopies. Two methyl groups of the NHCH(CH3)2 moiety are magnetically non-equivalent and are revealed in different chemical shifts in the 1H- and 13C-NMR spectra, but with equal hydrogen-hydrogen coupling constants in 1H-NMR (3J(H,H) = 6.4 Hz for both) and phosphorus-carbon coupling constants in 13C-NMR (3J(P,C) = 5.7 Hz for both). The NH protons reveal a triplet with apparent coupling constant of 10.1 Hz (due to geminal phosphorus-hydrogen and vicinal hydrogen-hydrogen couplings). The ipso and ortho carbon atoms of the 4-CH3-C6H4O moiety appear as doublets with 2J(P,C) = 6.5 Hz  3J(P,C) = 4.8 Hz. In the IR spectrum, the NH stretching vibrations appear at 3281 cm–1 and 3194 cm–1. The phosphorus chemical shift of the title compound was compared with some literature compounds to show the electronic and anisotropic effects of substituents attached to phosphorus. Manuscript profile

Abstract The synthesis and crystal structure of diphenyl [(S)-(–)-1-phenylpropanamido]-phosphate, (C6H5O)2P(O)[NH-(S)-(–)CH(C2H5)(C6H5)], was previously reported. Here, the spectroscopic features (1H-NMR, 13C{1H}-NMR, 31P{1H}-NMR and IR) are investigated. In the 1H-NMR and 13C{1H}-NMR spectra, the diastereotopic C6H5O groups show two sets of signals. Typically, in the 13C{1H}-NMR spectrum, the doublets at 151.08/151.20 ppm and 120.52/120.55 ppm, with 2JCP = 6.5/6.6 Hz for the first pair and 3JCP = 4.9/4.7 Hz for the second pair are associated to the diastereotopic ipso-C atoms and diastereotopic ortho-C atoms. In the 1H-NMR spectrum, the signals related to diastereotopic phenyl groups overlap with those of phenyl group of chiral amine. The ipso-carbon atom of chiral amine fragment appears a doublet signal at 144.85 ppm (3JCP = 2.7 Hz). The phosphorus signal (31P{1H}-NMR) appears at –0.49 ppm. in this work NMR and spectroscopic main part are going to be consider and proved because of the chiral importance in drug delivery. Keywords: Amidophosphodiester; IR; NMR; Phosphorus-carbon coupling constant Manuscript profile