Condensation catalysts

In a first full scale attempt at a new polymerisation process, the thermally unstable initiator was charged and heated to reaction temperature, but there was then an unforeseen delay of an horn before monomer addition was started. The rate of polymerisation effected by the depleted initiator was lower than the addition rate of the monomer, and the concentration of the latter reached a level at which an uncontrollable polymerisation set in which eventually led to pressure-failure of the vessel seals. Precautions to prevent such occurrences are detailed. In another incident, operator error led to catalyst, condensing styrene and acrylonitrile being ducted into an unstirred weighing tank instead of a reactor. When the error was recognised, the reacting mixture was dropped into drums containing inhibitor. One of the sealed drums had insufficient inhibitor to stop the reaction, and it slowly heated and eventually burst [1], The features and use of... 

Under dehydrating conditions, D-fmctose 137 will effectively react with amines to produce the corresponding imine product 138, which can be transformed into the aldohexose 139 by using zinc halide as catalyst. Condensation of 139 with another equiv. of amine followed by ring-closure and hydrolysis gives the 2-alkylamino-2-deoxy-D-glucopyranose 140 (O Scheme 63) [102]. 

Corma, A., Pomes, V., Martin-Aranda, R.M., Garcia, H., and Primo, J. 1990. Zeolites as base catalysts Condensation of aldehydes with derivatives of malonic esters. Applied Catalysis. 59, 237-248. 

C orma, A Martin-Aranda. RM Sanchez. F. Zeolites as base catalysts condensation of ben/aldchydc derivatives with activated methylcnic compinmds on germanium-substituted IauyjiS e. Journal of Catalysis, 1990 126. 192-198. 

If phenols and formaldehyde are reacted in the presence of acid catalysts, condensation products are obtained that do not contain reactive groups. These products can therefore neither react with themselves nor with other compounds and are termed novolacs. 

Empirical CH2CI3O3P Formula CCl3PO(OH)2 Properties Sol. in water and alcohol insol. in benzene and hexane Uses Catalyst condensation agent... 

Ammonia Dibutyltin maleate Dibutyltin oxide Fluorosulfonic acid Phosphine Sodium ethylate Sodium hydride Tetrabutyl titanate Tetraisopropyl titanate p-Toluene sulfonic acid Zirconium butoxide catalyst, condensation reactions Dibutyltin diacetate Piperidine catalyst, conductive polymers Iron (III) toluenesulfonate catalyst, conversion of acetylene to acetaldehyde Mercury sulfate (ic) catalyst, copolymerization Di butyl ether catalyst, cracking Zeolite synthetic... 

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