Cn. O'Callaghan et al., Synthesis and C-13 NMR assignment of ammonium benzylidenepropanedioates and benzylidenepropanediamides, J CHEM R-S, (12), 1998, pp. 732-733A
Mono- and di-ammonium benzylidenepropanedioates are synthesised, the molecu
lar structure of a mono-ammonium salt confirmed by X-ray diffraction, and t
he C-13 NMR spectra of the salts and the related benzylidenepropanediamides
assigned.