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Updated: Jul 27, 2025
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Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
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Bromination of
Demet Demirci Gültekin1, Arif Daştan2, Yavuz Taşkesenligil3
1Askale Vocational College, Department of Metallurgical Program, Atatürk University 25500 Erzurum, Turkey.
Beilstein Journal of Organic Chemistry
|June 7, 2023
Summary
This study confirms the original structure of a brominated norbornene adduct using X-ray crystallography, refuting a recent computational claim and proposed alternative mechanism. The findings reinforce established stereochemical assignment methods in organic chemistry.
Area of Science:
- Organic Chemistry
- Stereochemistry
- Computational Chemistry
Background:
- Previous work reported bromination of endo-7-bromonorbornene and structural elucidation via NMR spectroscopy.
- A recent study challenged these findings using machine learning-augmented DFT, proposing a revised structure and mechanism.
Purpose of the Study:
- To definitively confirm the structure of the brominated norbornene adduct.
- To refute the revised structure and proposed mechanism from Novitskiy and Kutateladze.
- To validate the reliability of NMR spectroscopy in stereochemical assignments.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy for initial structural elucidation.
- X-ray crystallography for ultimate structural confirmation.
- Mechanistic reasoning to evaluate proposed reaction pathways.
Main Results:
- The original structure assigned via NMR spectroscopy was confirmed by X-ray crystallography.
- The revised structure proposed by Novitskiy and Kutateladze was disproven.
- An alternative reaction mechanism involving skeletal rearrangement was refuted.
Conclusions:
- The study reaffirms the accuracy of the originally assigned structure through definitive crystallographic evidence.
- The computational NMR approach and proposed mechanism by Novitskiy and Kutateladze were shown to be erroneous.
- This work underscores the importance of experimental validation in organic structure determination and mechanistic studies.
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