como nucleofilo en el carbono del benzaldehído, realizando una reacción de condensación de Claisen-Schmidt (tipo de condensación aldolica cruzada). Particulares ○ Efectuar una condensación aldólica cruzada. ○ Obtener un producto de uso comercial. Diferencia entre una condensación aldólica cruzada y. Específicos Efectuar una condensación aldólica cruzada. Determinar el rendimiento de la reacción realizada y el punto fusión del producto obtenido.
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In cruuzada, a highly pure TMP is obtained, since the remaining formaldehyde condenses with TMP is to form easily removable CMF during one heat treatment under acidic conditions. Method for producing highly pure trimethylolpropane. In addition, formaldehyde remaining in TMP product is not the completely eliminated by a usual distillation.
ES2235425T3 – Tucked to produce highly pure trimethylolpropane. – Google Patents
Ejemplo comparativo 4 Comparative Example 4. Method for producing a trimethylolpropane TMP highly pure comprising the steps of: The present invention relates to a method of purifying a condensaciom TMP obtained by an aldol condensation and a subsequent crossed Cannizzaro reaction of NBAL of formaldehyde in the presence of a basic catalyst.
The present invention has been accomplished coneensacion on this finding. Para un procedimiento industrial, se prefieren las sales de sodio o potasio.
The gas chromatographic analysis showed that the purity of TMP obtained was In the present invention, before the subsequent heat treatment, a component of high boiling point and an inorganic salt, including the salt of residual formic acid obtained as a byproduct during the crossed Cannizzaro reaction, the TMP crude thus separated was previously removed.
The solvent may be used alone or in combination of two or more.
File:Cuatro productos reacción aldólica cruzada.svg
Cindensacion, TMP has come to be widely used and particularly in the use as raw material for ultraviolet curable resins, TMP presenting a higher purity to previously reached require. Deactivation is carried out by adding the acid to cruzasa crude TMP in an amount 0. It is known that the condensation products mentioned above are thermally decomposed under acidic consensacion publication of Japanese Patent No. The solvent for the extraction may include ketones such as methyl ethyl ketone and methyl isobutyl ketone, aldehydes such as NBAL, also serving as material of alcohols such as isobutyl alcohol and isopropyl alcohol, and esters such as butyl acetate starting, and are typically used in a total amount of 0.
TMP obtained by the reaction between NBAL and formaldehyde in the presence of basic catalyst in the two-stage process of the aldol condensation and aldplica subsequent crossed Cannizzaro reaction contains the impurities hardly removable by distillation. The present invention is further explained by reference to the following examples which should not be construed as limiting the scope of the present invention.
Condensación de aldehídos simples by Adrian Yazan on Prezi
The content of the remaining formaldehyde in the final TMP was 30 ppm. Recientemente, el TMP ha empezado a ser ampliamente conrensacion y particularmente en el uso como materia prima para resinas curables con ultravioleta, presentando el TMP una pureza superior a la que antes se ha llegado a requerir. Formaldehyde used in the present invention as starting material can be used as an aqueous solution or solid as paraformaldehyde. Without adding phosphoric acid and without subjecting to heat treatment, g of the distillate mainly comprising TMP by distillation at under a reduced pressure of Pa 1 Torr using a column with Sulzer-packed 10 theoretical stages purified.
With such heat treatment, the component hardly removable from TMP by distillation alxolica thermally decomposed or chemically combines to form an easily removable component of TMP by distillation. The basic cruzdaa is used in an amount of 1.
The final product quality is adversely affected by the remaining formaldehyde even in a small amount. Although the condensation products are decomposed by the heat treatment using excess amount of acid, a colored component from high boiling point, which is difficult to remove TMP by distillation component curzada formed.
Sin embargo, de manera perjudicial el color fundido del TMP final fue tan elevado como Then, after further adding Therefore it occurs industrially advantageously a highly pure TMP usable as a raw material for ultraviolet curable resins.
The Japanese Patent Publication No. The aldol condensation and the subsequent crossed Cannizzaro reaction may be carried out in the presence of water in an amount of 2 to 20 times by weight of NBAL. Thus, a highly pure TMP has not been obtained with conventional distillation methods.
Purification of propylene oxide using an aqueous acetone extractive distillatin agent. The content of the remaining formaldehyde in the final TMP was 5 ppm. To completely remove the impurities such as formaldehyde, MDF, etc. Process for separating alcohols from mixtures of alcohols, water and other compounds.
A method of further purification is described in DD-A In the present invention, as the load of distillation column is reduced, the distillation apparatus improved from the economic viewpoint with respect to the structure and operatively allowing it to produce a highly pure TMP advantageously in industrial scale. The method proposed in Japanese Patent Publication No.
These basic catalysts may be used alone or in combination of two or more. The product mixture from the reaction of NBAL and formaldehyde is separated, if necessary after removing formaldehyde unreacted by condensation in crude TMP and the formic acid salt, obtained as a byproduct during the crossed Cannizzaro reaction by a solvent extraction or hot filtration after condensing.
The liquid reaction mixture from the two-stage process contains a formic acid salt formed during the crossed Cannizzaro reaction. Method for producing a highly pure trimethylolpropane according to claim 1, wherein component removing high boiling point and the inorganic salt is carried out after deactivating sodium formate present in the crude trimethylolpropane, wherein the deactivation is carried out by means of adding an acid to crude TMP in an amount 0.
Trimethylolpropane hereinafter referred to as “TMP” has been produced by a known two-stage process see for example, DE-A comprising an aldol condensation between n-butyl aldehyde hereinafter referred hereinafter as “NBAL” and formaldehyde in the presence of a basic catalyst and a subsequent crosslinking reaction between the aldol condensation product and formaldehyde in a basic catalyst Cannizzaro.
The purity of TMP obtained was A process for the decomposition of polyhydric alcohols in the synthesis of high-boiling by-products formed. For an industrial process, the sodium or potassium salts are preferred. Por tanto, se produce a escala industrial de manera ventajosa un TMP sumamente puro utilizable como materia prima para resinas curables con ultravioleta.
The impurities are free formaldehyde, condensation products of TMP and formaldehyde, methanol contained in formalin starting, methanol formed during the crossed Cannizzaro reaction, condensation products of methanol, TMP and formaldehyde, etc.
Masters and doctoral program in Chemical Sciences
For example, the two-phase process using sodium hydroxide is expressed by the following reaction scheme. In the method known in the art, the liquid reaction mixture is distilled after removing most of the formic acid salt by a solvent extraction or aldo,ica hot filtration after condensing and TMP distillate resulting crude is fruzada to obtain thereby a final TMP with a high purity.
Such an acid may include mineral acids such aleolica phosphoric acid and sulfuric acid and organic acids such as p-toluenesulfonic acid and methanesulfonic acid. In the present invention, it is not necessary to use expensive cation exchange resins, etc.
In the present invention, as described above, after first removing the inorganic salt such as sodium formate, and the component of high boiling the condensacon TMP, the treated TMP is subjected to heat treatment under acidic conditions. A process for obtaining trimethylolpropane-enriched product streams from the secondary streams of trimethylolpropane. However, when TMP contains the formic acid salt and the component of high boiling condensation products are decomposed hard by heat treatment in the presence of acid even in an amount equivalent to the amount of formic acid saltleaving obtained this a highly pure TMP mode.