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Odd-Even Effects Leading to Alternating Polymerization and Macrocyclization in Nitroaldol Reaction Systems.
Yunchuan Qi1, Mubarak Ayinla1, Zhen Yang1
1Department of Chemistry, University of Massachusetts Lowell, One University Ave., Lowell, MA, 01854, USA.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|April 7, 2025
Summary
Dynamic nitroaldol reactions show alternating macrocyclization and polymerization. Alkyl chain folding in dinitroalkanes dictates whether lowellane macrocycles or polymers form.
Area of Science:
- Organic Chemistry
- Polymer Chemistry
- Supramolecular Chemistry
Background:
- Dynamic covalent chemistry offers pathways to complex molecular architectures.
- Nitroaldol reactions are versatile tools in organic synthesis.
Purpose of the Study:
- To investigate the influence of dinitroalkane chain length on nitroaldol reaction outcomes.
- To explore the formation of macrocycles versus polymers in dynamic systems.
Main Methods:
- Utilizing dynamic nitroaldol reactions between aromatic dialdehydes and linear α,ω-dinitroalkanes.
- Varying the number of carbon atoms in the dinitroalkane chain (even vs. odd).
Main Results:
- Reactions with even-carbon dinitroalkanes predominantly formed lowellane macrocycles.
- Reactions with odd-carbon dinitroalkanes predominantly yielded polymers.
- Alkyl chain folding patterns were identified as critical factors influencing reaction pathways.
Conclusions:
- The length and folding of alkyl chains in dinitroalkanes control the macrocyclization vs. polymerization outcome.
- Dynamic nitroaldol reactions provide a tunable platform for synthesizing macrocycles or polymers.
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