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Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Nonaromatic amidine derivatives as acylation catalysts.
Vladimir B Birman1, Ximin Li, Zhenfu Han
1Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, St. Louis, Missouri 63130, USA. birman@wustl.edu
The catalytic activity of bicyclic amidines and isothioureas in acylation reactions depends on ring size. Diazabicyclononane (DBN) and its thia-analogue (THTP) are highly effective acylation catalysts.
Area of Science:
- Organic chemistry
- Catalysis
- Reaction mechanisms
Background:
- Nonaromatic bicyclic amidines and isothioureas are organic compounds with potential catalytic applications.
- Acylation reactions are fundamental transformations in organic synthesis.
Purpose of the Study:
- To investigate the catalytic activity of nonaromatic bicyclic amidines and isothioureas in acylation reactions.
- To determine the influence of ring size on the catalytic performance of these compounds.
- To identify highly active catalysts for acylation.
Main Methods:
- Synthesis and characterization of various nonaromatic bicyclic amidines and isothioureas.
- Evaluation of their catalytic activity in representative acylation reactions.
- Structure-activity relationship analysis based on ring sizes.
Main Results:
- Catalytic activity was found to be highly dependent on the sizes of both rings within the bicyclic structures.
- Diazabicyclononane (DBN) demonstrated significant acylation catalytic activity.
- The thia-analogue of DBN, THTP (thia-diazabicyclononane), exhibited even higher catalytic activity.
Conclusions:
- Ring size is a critical factor governing the efficiency of bicyclic amidine and isothiourea catalysts in acylation.
- DBN and particularly THTP are identified as potent catalysts for acylation reactions, offering potential for synthetic applications.
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