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Updated: Jun 1, 2025
06:18
Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate
Published on: April 24, 2018
8.3K
Understanding 2-(Nitromethylene)hexahydropyrimidin-5-ol Reaction Processes and NMR Spectroscopy: A Theoretical and
Ramon S da Silva1, Diego P Sangi2, Rodrigo G Amorim1
1Departamento de Física - Instituto de Ciências Exatas - ICEx, Universidade Federal Fluminense, Volta Redonda, Rio de janeiro 27213-145,Brazil.
ACS Omega
|January 20, 2025
Summary
Researchers explored the reaction of ketene dithioacetals, predicting two products using density functional theory (DFT). The study confirmed the more favorable formation of 2-(nitromethylene)hexahydropyrimidin-5-ol through experimental synthesis and analysis.
Area of Science:
- Organic Chemistry
- Computational Chemistry
Background:
- Ketene dithioacetals are versatile building blocks in organic synthesis.
- They find applications in pharmaceuticals, agrochemicals, and material science.
Purpose of the Study:
- To investigate the reaction mechanism between 1,3-diaminopropan-2-ol and 1,1-bismethylsulfanyl-2-nitroethylene.
- To theoretically predict and experimentally validate the formation of heterocyclic products.
Main Methods:
- Density Functional Theory (DFT) calculations were employed to study reaction pathways.
- Experimental synthesis and characterization using IR, NMR, and high-resolution mass spectrometry were performed.
- GIAO/B3LYP calculations were used to predict NMR chemical shifts.
Main Results:
- Two potential products, a six-membered and a five-membered heterocycle, were theoretically predicted.
- Both reaction mechanisms were found to be exothermic.
- The formation of 2-(nitromethylene)hexahydropyrimidin-5-ol was energetically favored and experimentally confirmed.
- Calculated NMR chemical shifts showed good agreement with experimental data.
Conclusions:
- The study successfully combined theoretical predictions with experimental validation for ketene dithioacetal reactions.
- DFT calculations provide reliable insights into reaction mechanisms and product selectivity.
- The findings contribute to a deeper understanding of ketene dithioacetal chemistry and potential applications.
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