Spectroscopic elucidation of hydrogensquarate and ester amide of squaric acid of 2-cloro-3-amino-pyridine

摘要

Novel derivatives of squaric acid with 2-chloro-3-amino-pyridine, i.e. hydrogensquarate and ester amide of squaricacid are synthesized, isolated and spectroscopically characterized in solution and in solid-state. Methods as conven-tional and linear polarized IR-spectroscopy of oriented colloid suspensions, UV-spectroscopy, ~1H- and ~(13)C-NMR, massspectrometry (positive and negative ESI, FAB, HPLC tandem MS/MS), TGV and DSC methods are used. Quantumchemical ab initio and DFT calculations are performed, supporting the obtained optical experimental data.