Zinc chloride catalysts

Friedel-Crafts reaction of ahyl alcohol with benzene or alkylbenzene yields many kinds of products, in which the reaction species and the product ratio depend on the type of catalyst. Zinc chloride is the most effective catalyst for producing ahyl compounds by this reaction (32). 

Among the epoxides possessing one or more polar atoms near the ring may be mentioned epichlorchydrin Eq. 647), which has been cleaved with a number of alkylmercaptans. h .1 ao- Of interest jg the fact that in addition to the conventional alkaljno catalysts, zinc chloride has also been found effective in promoting this particular reaction.17 4 Attack takes place at the terminal epoxide carbon atom furthest from the polar atom in every instance. 

Addition of propargyl chlorides to l -dienes.1 The homogeneous catalyst zinc chloride-diethyl ether effects the addition of propargyl chlorides to acyclic 1,3-dienes at low temperatures. The products undergo cyclization at higher temperatures. An example is the addition of the propargyl chloride (1) to isoprene (equation I). Similar reactions are obtained on reaction of 1 with 1,3-butadiene, piperylene, and 2,3-dimethyl-1,3-butadiene. 

ALDOL CONDENSATION, CATALYSTS Bis(p-methoxypheny])telluroxide. Phase-transfer catalysts. Zinc chloride. 

ChloromethyUttion of nilrophenols. o-Nitrophcnols and, in some instances, j-nitrophenols can be chloromethylated with the reagent. The reaction fails with dinitro-phcnols. A catalyst (zinc chloride) is required for the reaction,... 

In the presence of a catalyst (zinc chloride) the combination thiophene-formaldehyde-hydrochloric acid leads to 2,2 -dithienylmethane as the major product (50-65%) higher condensation products (9, n = 1, 2, etc.) are also formed, in lower yields. When the reaction with formaldehyde is applied to... 

Various catalysts zinc chloride, hydrogen chloride, alkalies, etc. 

Catalysts zinc chloride, sulfuric acid, hydrogen chloride, etc. 

Reaction of Epoxidized Esters with Alcohols. Alcoholysis study of epoxidized RME with ethanol and heptanol was condueted to determine the best eleavage conditions of the oxirane group acid catalysts (zinc chloride, PTSA) and a basic catalyst (sodium methylate) were tested. The results are reported in Tables 9 and 10. As expected, no cleavage of the oxirane group occurred when no catalyst or basic catalyst was used at temperatures <100°C. 

Mercaptoethanol is more reactive than ethylene glycol and the best general method for the preparation of hemithioketals appears to be reaction of the two components in the presence of the mild catalyst zinc chloride and of sodium sulphate as... 

H-NMR (200.13 MHz with a sweep width of 3600 Hz) and C-NMR (50.33 MHz with a sweep width of 13.5 kHz) spectroscopy were used to study the microstructiu e of fiunarate-based polyesters for use in bioresorbable bone cement composites and the impact of their microstructure on the physical properties as well as hydrolysis of the cements [145]. Poly(propylene fumarate)s (PPF) were synthesized by the transesterification polycondensation of diethyl fumarate (DEE) with different diols ( )-l,2-propanediol (PD), (S)-(+)-l,2-propanediol, 2-methyl-1,3-propanediol, and 2,2-dimethyl-1,3-propanediol in the presence of p-toluenesulfonic acid monohydrate (PTSA) or metal-containing catalysts zinc chloride, aluminum trichloride, ti-... 

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