Lewis-acid catalyzed organic reactions in water. The case of AlCl(3), TiCl(4), and SnCl(4) believed to be unusable in aqueous medium.
Classical Lewis acids such as AlCl(3), TiCl(4), and SnCl(4), believed to be unusable as catalysts in aqueous medium, efficiently catalyzed regio- and stereoselective azidolysis and iodolysis of alpha,beta-epoxycarboxylic acids in water at pH 4.0 and 1.5, respectively. The concept of water-tolerant metal-salt is reexamined in direct relationship to the aqua ion hydrolysis constant.
Fringuelli
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Dipartimento di Chimica, Università di Perugia, I-06123 Perugia, Italy. frifra@unipg.it
Pizzo
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Vaccaro
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