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Updated: Jul 15, 2026

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes
Published on: September 12, 2018
Solution structure of some lambda(3) Iodanes: an (17)O NMR and DFT study
Francesca Mocci1, Gianluca Uccheddu, Angelo Frongia
1Dipartimento di Scienze Chimiche, Università di Cagliari, Complesso Universitario, S.S. 554, Bivio per Sestu, I-09042 Monserrato (CA), Italy. francy@dsc.unica.it
Abstract:
The structure of a series of I-O bonded bis(acyloxy)iodoarenes and benzoiodoxolones in chloroform solution has been investigated by 17O NMR spectroscopy and by density functional theory (DFT) calculations, employing the PBE0 functional together with the LANL2DZ basis set extended with polarization (d) and diffuse (p) functions. This combined approach allowed us to ascertain that, although these classes of lambda(3) iodanes maintain in chloroform solution their solid state "T-shaped" structure, a degenerate [1,3] sigmatropic shift of iodine between the two oxygens of the acyloxy groups occurs in solution. The energy barrier involved in this process differs in the two classes, thus causing significant differences in the 17O NMR spectra, at room temperature, of the two classes of compounds.
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