Zinc Compounds Zirconium chloride

Tributyl (tetradecyl) phosphonium chloride Tri (P,P -dichloroisopropyl) phosphate Trimethyl phosphate Triphenylphosphine oxide Tris-dibromopropylisocyanurate 4-Vinylcyclohexene Zeolite Zinc oxide Zirconium potassium hexafluoride flame retardant compounds Chlorine... 

The redistribution reaction in lead compounds is straightforward and there are no appreciable side reactions. It is normally carried out commercially in the liquid phase at substantially room temperature. However, a catalyst is required to effect the reaction with lead compounds. A number of catalysts have been patented, but the exact procedure as practiced commercially has never been revealed. Among the effective catalysts are activated alumina and other activated metal oxides, triethyllead chloride, triethyllead iodide, phosphorus trichloride, arsenic trichloride, bismuth trichloride, iron(III)chloride, zirconium(IV)-chloride, tin(IV)chloride, zinc chloride, zinc fluoride, mercury(II)chloride, boron trifluoride, aluminum chloride, aluminum bromide, dimethyl-aluminum chloride, and platinum(IV)chloride 43,70-72,79,80,97,117, 131,31s) A separate catalyst compound is not required for the exchange between R.jPb and R3PbX compounds however, this type of uncatalyzed exchange is rather slow. Again, the products are practically a random mixture. 

A rapid procedure has been described10 based on sodium peroxide bomb fusion, for the determination of silicon and halogen in fluorine-containing organosilicon compounds and resins. The silicon is separated from the decomposition product as zinc silicate and estimated gravimetrically as silica. The filtrate is concentrated, acidified and, when necessary, reduced with sulphur dioxide. Chloride, bromide or iodide is then determined by the usual methods. Fluoride can be determined in neutral solution either gravimetrically as calcium fluoride, or volumetrically with zirconium tetrachloride or thorium nitrate, or directly in the decomposition solution by titration with zirconium tetrachloride. 

Shaw and co-workers used a mixed Lewis acid approach to synthesize chiral furanmethanol derivatives from glycals. These compounds are important intermediates in the synthesis of many biologically significant compounds and serve as precursors for furanmethanes and 3-acylfurans. Reaction of a selectively protected 6-azido glycal with zirconium(IV) chloride and zinc(II) iodide gave the desired chiral furan selectively in 74% yield. 

Many of the palladium- and nickel-catalysed reactions of alkenyl-aluminium or -zirconium compounds which fail or give low yields of cross-coupled products can be promoted to give the desired product in high yield by the addition of catalytic amounts of zinc chloride. " Trisubstituted olefins (40), for example, can be synthesized in good yield (ca. 70%) from the metal complex (38) in the presence of a palladium or nickel phosphine complex and zinc chloride. This reaction is particularly attactive for the one-pot synthesis of natural products containing... 

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