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Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Pyrrolizine-1,3-dione.
Hamish McNab1, James Montgomery, Simon Parsons
1School of Chemistry, The University of Edinburgh, West Mains Road, Edinburgh, UKEH9 3JJ. H.McNab@ed.ac.uk
Organic & Biomolecular Chemistry
|August 10, 2010
Summary
Pyrrolizine-1,3-dione was synthesized and its chemical properties explored. This study details its reactions, including coupling with diazonium salts and thermal decomposition, yielding novel heterocyclic compounds.
Area of Science:
- Organic Chemistry
- Heterocyclic Chemistry
Background:
- Pyrrolizine-1,3-diones are a class of nitrogen-containing heterocyclic compounds.
- Understanding their reactivity is crucial for synthetic applications.
Purpose of the Study:
- To synthesize pyrrolizine-1,3-dione 4.
- To investigate the chemical properties and reactivity of compound 4.
- To explore the synthesis of novel heterocyclic derivatives.
Main Methods:
- Oxidation of alcohol 2 using pyridinium chlorochromate to yield dione 4.
- Reactions of dione 4 with methanol, diazonium salts, and DMF acetal.
- Flash vacuum pyrolysis (FVP) of a Meldrumsated derivative.
- X-ray crystallography for structure confirmation.
Main Results:
- Pyrrolizine-1,3-dione 4 was successfully synthesized.
- Compound 4 exhibited ketone properties and lactam ring-opening under basic conditions.
- Coupling with diazonium salts yielded hydrazone 15, confirmed by X-ray crystallography.
- FVP of derivative 18 produced pyronopyrrolizine 20.
- Reaction with DMF acetal gave derivative 22.
Conclusions:
- Pyrrolizine-1,3-dione 4 is a versatile synthetic intermediate.
- The study demonstrates novel transformations of the pyrrolizine-1,3-dione core.
- New heterocyclic compounds were accessed through various chemical reactions.
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