Triphenyl isocyanurate

In the reaction of the phenyl phosphoramidate anion 53 (R = Ph) with carbon dioxide only triphenyl isocyanurate is obtained because the generated phenyl isocyanate trimerizes under the reaction conditions. Also, from sodium diethyl A -alkoxy-phosphoramidate (R = OR) and carbon dioxide only 1,3,5-trialkoxyisocyanurates are obtained . 

A comprehensive review of trimerization catalysts appeared in 1985 . The need to synthesize high purity triphenyl isocyanurate as an activator for the continuous anionic polymerization of caprolactam to nylon-6 prompted the development of new catalysts, which trimerize aryl isocyanates at a fast rate at room temperature, achieving virtually quantitative yields. Examples of these new supercatalysts are tetrabutylammonium fluoride (TBAF), cesium fluoride and [P(MeNCH2CH2)3N]. The latter catalysts gives a 97 % yield of triphenyl isocyanurate after 3.8 min at room temperature (catalyst concentration, 0.33 mol%). Likewise, TBAF affords 98.8 % of triphenyl isocyanurate after 5 min at room temperature. A similar fast trimerization can be achieved using potassium t-butoxide as the catalyst . 

The formation of aromatic isocyanate trimers is of economic importance, because rigid insulation foams, having isocyanurate structures built into their network structure, are produced from aromatic diisocyanates. Triphenyl isocyanurates with hydroxyl or carboxyl groups in their p-positions can be obtained on hydrolysis of McsSiO- and McsSiOCO-groups, respectively, with hydrochloric acid °. Such trifunctional compounds are of use in the construction of network polymers. The mechanism of the phenyl isocyanate trimer-ization, using Pd(o) diimide catalysts was elucidated recently. The initial steps of this trimerization reaction involve a chain growth process as encountered in the anionic homopolymerization of isocyanates. 

At 200 °C, the reaction of methyl isothiocyanate and alkylene oxide gives trimethyl isocyanurate. This reaction involves the trimerization of methyl isothiocyanate followed by stepwise replacement of the sulfur by oxygen via spiro compounds. Phenyl isothiocyanate reacts with ethylene oxide to give a mixture of triphenyl isocyanurate and 3-phenyloxazolidine-2-one 90 °. The formation of the oxazolidone is caused by the reaction of the initially formed 2-phenylimino oxathiolene 89 with ethylene oxide in the presence of the catalysts... 

FLUORINECOMPOUNDS,ORGANIC - FLUORINATED AROMATIC COMPOUNDS] (Volll) N,Ny,Nyy-Tris(triphenyl- stannyl)isocyanurate [752-74-9]... 

Tri-t-butylphenyl 2-butyl-2-ethyl-1,3-propanediol phosphite Triethyl phosphonoacetate 1,3,5-Trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene Triphenyl phosphite Tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate Tris (2,4-di-t-butylphenyl) phosphite 1,1,3-Tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane Zinc dibutyidithiocarbamate Zinc palmitate Zinc stearate... 

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