(E)-Di-iodination of Alkynes Using Dried Dowex H+/NaI Approach
Juri M Timonen1, Petri A Turhanen1
1School of Pharmacy, Biocenter Kuopio, University of Eastern Finland, P.O. Box 1627, FIN-70211 Kuopio, Finland.
Abstract:
We investigated the usefulness of the dried Dowex H+/NaI approach for the selective di-iodination of alkynes. The Dowex H+/NaI approach selectively produces only (E)-di-iodinated products; it is very straightforward and nontoxic. The utilization of 2-propanol as a solvent in the reactions can be considered as a "green" approach and the method maybe extended to radio-iodination. The method allows access to highly important building blocks. An initial example of the di-iodination and esterification in the same one-pot reaction is also presented.
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