Premium
Synthesis and characterization of isomeric cis ‐ and trans ‐pyrrone model compounds
Author(s) -
Young Philip R.
Publication year - 1973
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570100309
Subject(s) - chemistry , polymer , pyromellitic dianhydride , thermal stability , characterization (materials science) , benzimidazole , polymer chemistry , spectral line , infrared spectroscopy , organic chemistry , polyimide , nanotechnology , materials science , physics , layer (electronics) , astronomy
Isomeric cis ‐ and trans ‐imidazopyrrolones, obtained from the reaction of pyromellitic di‐anhydride and o ‐phenylenediamine, were prepared as models for pyrrone polymers. The characterization of these model compounds, which represent the repeat unit of the completely cyclized polymer, provided information which could not be obtained by studying the polymer itself. Isomerism was proven by the nuclear magnetic resonance spectra of soluble ester‐benzimidazole derivatives. This study indicated that a single band around 1755 cm −1 should appear in the infrared spectrum of the completely cyclized polymer. The high melting points of the model imidazopyrrolones indicate the extreme thermal stability to be anticipated from perfectly formed pyrrone polymers.