Spectral evidence for generic charge → acceptor interactions in carbamates and esters
Erode N Prabhakaran1, Shama Tumminakatti2, Kamal Vats1
1Department of Organic Chemistry, Indian Institute of Science Bangalore Karnataka India - 560 012 eprabhak@iisc.ac.in.
RSC Advances
|May 2, 2022
Summary
Nuclear Magnetic Resonance (NMR) and FT-IR spectral data reveal charge stabilization in alkyl carbamates and esters. This explains unusual properties observed in homologous alcohol derivatives.
Area of Science:
- Organic Chemistry
- Spectroscopy
Background:
- Alkyl carbamates and esters exhibit anomalous properties.
- Understanding the electronic structure of these compounds is crucial.
Purpose of the Study:
- To investigate the electronic properties of the R-O-C=O group in alkyl carbamates and esters.
- To correlate spectral data with observed chemical behaviors.
Main Methods:
- Analysis of 1H NMR, 13C NMR, and FT-IR spectral data.
- Examination of homologous series of alkyl carbamates and esters.
Main Results:
- Observed R-group-dependent negative charge stabilization at the carbonyl oxygen.
- Demonstrated charge donation to generic acceptors at the Cα of even alkyl alcohols.
Conclusions:
- The spectral findings explain the anomalous properties of alkyl carbamates and esters.
- Electronic effects within the R-O-C=O moiety are key to their reactivity.
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