Leveraging the Micellar Effect: Gold-Catalyzed Dehydrative Cyclizations in Water at Room Temperature
Stefan R. K. Minkler, Nicholas A. Isley, Daniel J. Lippincott, Norbert Krause* and Bruce H. Lipshutz*
*Dortmund University of Technology, Otto-Hahn-Strasse 6, D-44227 Dortmund, Germany; University of California, Santa Barbara, California 93106, United States, Email: norbert.krausetu-dortmund.de, lipshutzchem.ucsb.edu
S. R. K. Minkler, N. A. Isley, D. J. Lippincott, N. Krause, B. H. Lipshutz, Org. Lett., 2014, 16, 724-726.
DOI: 10.1021/ol403402h (free Supporting Information)
see article for more reactions
Gold-catalyzed cyclizations of diols and triols to the corresponding hetero- or spirocycles take place in an aqueous medium within nanomicelles, where the hydrophobic effect is operating, thereby driving the dehydrations, notwithstanding the surrounding water. By the addition of simple salts such as sodium chloride, reaction times and catalyst loadings can be significantly decreased.
see article for more examples