Chemical degradation products of lignin and humic substances. Part II: Synthesis, structure verification and liquid) chromatographic separation of chlorinated protocatechualdehydes (3,4-dihydroxybenzaldehydes], 5-hydroxyvanillins (3,4-dihydroxy-5-methoxybenzaldehydes) and gallaldehydes (3,4,5-trihydroxybenzaldehydes)

Article abstract of DOI:10.1016/0045-6535(94)90423-5

All possible chloroprotocatechualdehydes, chlorogallaldehydes, 5-bromoprotocatechualdehyde and chloro-5-hydroxyvanillins (except 2-chloro-5-hydroxyvanillin) were synthesized. Their purity and structures were examined by liquid chromatography, mass spectrometry and other spectroscopic measurements. The details of the synthesis, liquid chromatographic separation and mass spectrometric features are discussed.