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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A process for the decomposition of polyhydric alcohols cruzzada the synthesis of high-boiling by-products formed. To minimize the occurrence of byproducts and increase selectivity of the objective TMP, preferred set the amount of the basic catalyst according to the reaction conditions. Ejemplo comparativo 1 Comparative Example 1. Sin embargo, de manera perjudicial el color fundido del TMP final fue tan elevado como To completely remove the impurities such as formaldehyde, MDF, etc.
Ejemplo comparativo 2 Comparative Example 2. The content of the remaining formaldehyde in the final TMP was 1 ppm. The gas chromatographic analysis showed that the purity of TMP obtained was The basic catalyst is used in an amount of 1. In the aldoliica invention, as described above, after first removing the inorganic salt such as sodium formate, and the component of high boiling the crude TMP, the treated TMP is subjected to heat treatment under acidic conditions.
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.
ES2235425T3 – Tucked to produce highly pure trimethylolpropane. – Google Patents
The present invention relates to a method of producing trimethylolpropane which is useful as a raw material for polyester resins, alkyd resins, polyurethane resins, polycarbonate resins, plasticizers, lubricating oils, surfactants, basis for cosmetics, reactive monomers, etc. As a result of extensive aldolics in the production method of TMP to eliminate the above problems, the inventors have found that a highly pure TMP is obtained from a crude TMP by previously removing a component of high boiling point and an inorganic salt such as sodium formate, the crude TMP, heat-treating the treated TMP under acidic conditions, and purifying the heat-treated TMP by distillation, etc.
The content of the remaining formaldehyde in the final TMP was 30 ppm. 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. However, since TMP after the solvent extraction, the hot filtration, etc.
After removing the component and high boiling aaldolica salt of crude TMP, the resultant TMP distillate is subjected to a heat treatment under acidic conditions.
These basic catalysts may be used alone or in combination of two or more. In the present invention, it is not necessary to use expensive cation exchange resins, etc.
TMP obtained by purification of crude TMP cruzadw the method of the present invention has such a high purity as 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 a hot filtration after condensing and TMP distillate resulting crude is rectified to obtain thereby a final TMP with a high purity.
Method for producing highly pure trimethylolpropane. Thus, a highly pure TMP has not been obtained with conventional distillation methods.
Masters and doctoral program in Chemical Sciences
The Japanese Patent Publication No. Such an acid may include mineral acids such as phosphoric acid and sulfuric acid and organic acids such as p-toluenesulfonic acid and methanesulfonic acid. 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.
Para un procedimiento industrial, se prefieren las sales de sodio o potasio. Ejemplo comparativo 4 Comparative Example 4. The content of the remaining formaldehyde in the final TMP was 3 ppm. 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 the subsequent crossed Cannizzaro reaction contains the impurities hardly removable by distillation.
File:Cuatro productos reacción aldólica – Wikimedia Commons
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. Purification of propylene oxide using an aqueous acetone extractive distillatin agent.
The method proposed in Japanese Patent Publication No. A process for obtaining trimethylolpropane-enriched product streams from the secondary streams of trimethylolpropane. Recientemente, el TMP ha empezado a ser ampliamente utilizado 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.
The molar ratio of formaldehyde to be used in the method with NBAL is 3. In addition, 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. Ejemplo comparativo 3 Comparative Example 3. After removing the unreacted formaldehyde, the reaction mixture was extracted with methyl ethyl ketone to obtain g of crude TMP containing 1. 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.
However, when TMP contains the formic aldolicw 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. The reaction was complete after 0. However, the cast detrimentally final TMP color was as high as Deactivation is carried out by adding the acid to the crude TMP in an amount 0. Process for separating alcohols from mixtures of alcohols, water and other compounds.
The content of the remaining formaldehyde in the final TMP was 5 ppm.