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The cis – trans isomerization of (thio)amides was studied by DFT calculations to get the model for the higher preference for the cis conformation by guided predictive chemistry, suggesting how to select the alkyl/aryl substituents on the C/N atoms that lead to the trans isomer. Multilinear analysis, together with cross-validation analysis, helped to select the best fitting parameters to achieve the energy barriers of the cis to trans interconversion, as well as the relative stability between both isomers. Double experimental check led to the synthesis of the best trans candidate with sterically demanding t -butyl substituents, confirming the utility of predictive chemistry, bridging organic and computational chemistry.
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Discovering Isomerism: A Guided-Inquiry Computational Exercise for Undergraduate Organic Chemistry
This paper provides a guided-inquiry exercise designed to help sophomore level undergraduate students discover isomerism in the organic chemistry curriculum. The activity teaches students to use Gaussian and GaussView software packages to create molecules and setup calculations to explore chemical properties. The students, unknown to them, create cis- and trans- isomers of simple molecules and analyze their potential energies and nuclear repulsion energies. The class uses this information to discover the stability of trans-isomers relative to cis-isomers. This provides students with a clearer understanding of the impact of nuclear repulsions on the final geometry of the molecule. Student assessment of the activity has been highly positive and points to the need for regular integration of such assignments into the Organic Chemistry curriculum.
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- Award ID(s):
- 1708635
- PAR ID:
- 10274722
- Date Published:
- Journal Name:
- The chemical educator
- Volume:
- 23
- ISSN:
- 1430-4171
- Page Range / eLocation ID:
- 39-41
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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