Synthesis and spectral study of N-2-(3 '-phthalidyl)phthalazin-1-one

N-2-(3'-Phthalidyl)phthalazin-1-one was synthesized by the condensation of 2-carboxybenzaldehyde with hydrazine hydrate using polyphosphoric acid as c atalyst and solvent. Its H-1 and C-13 NMR spectra were completely assigned utilizing the two-dimensional H-1-detected heteronuclear one-bond (HMQC) an d multiple-bond (HMBC) techniques together with H-1-H-1 COSY and NOESY (hom onuclear Overhauser and chemical exchange spectroscopy) correlation techniq ues. These techniques were also valuable in assigning the protons of its hy drazinolysis product, which were previously incompletely reported because o f the overlap of proton signals. Copyright (C) 1999 John Wiley & Sons, Ltd.