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Some Applications of Zirconium(IV) Tetrachloride (ZrCl4) and
Zirconium(IV) Oxydichloride Octahydrate (ZrOCl2.8H2O)
as Catalysts or Reagents in Organic Synthesis
H. Firouzabadi* and M. Jafarpour
Department of Chemistry, College of
Sciences, Shiraz University, Shiraz 71454, Iran
(Received 24 December 2007, Accepted 12 February 2008)
Both ZrCl4 and
ZrOCl2.8H2O are commercially available solid
chemicals. Due to their low toxicities (LD50 [ZrCl4
oral rate] = 1688 mg/kg), (LD50 [ZrOCl2.8H2O
oral rate] = 2950 mg/kg), low costs, ease of handling, high
activity, the zirconium(IV) compounds are potential green catalysts or
reagents which are of importance from different views. In this review we
have paid attention to the applications of these compounds as reagents
or catalysts in Friedel-Crafts reactions, Fries rearrangements,
reduction and oxidation reactions, cycloaddition and
hydrometalation reactions, protection and deprotection of
functional groups, reactions of epoxides, iodination of
alcohols, S-alkylation of thiols with alcohols, Michael
addition, condensation of indoles with carbonyl compounds,
Claisen ester condensation, Baylis-Hillman reaction, preparation
of organozirconium compounds and some other miscellaneous reactions.
Keywords: ZrCl4 and ZrOCl2.8H2O,
Friedel-Crafts reaction, Fries rearngement, Reduction, oxidation,
cycloaddition, and hydrometalation, Michael addition, Claisen
condensation, Baylis-Hillman reaction |
