CONDENSACION ALDOLICA CRUZADA PDF

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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Therefore it occurs industrially advantageously a highly pure TMP usable as a raw material for ultraviolet curable resins. The present invention relates to a method of purifying a crude TMP obtained by an aldol condensation and a subsequent crossed Cannizzaro reaction of NBAL of formaldehyde in the presence of a basic catalyst. 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.

Such an acid may include mineral acids such as phosphoric acid and sulfuric acid and organic acids such as p-toluenesulfonic acid coondensacion methanesulfonic acid. The present invention has been accomplished based on this finding.

Method for producing highly pure trimethylolpropane. The first stage aldol condensation and the alrolica stage crossed Cannizzaro reaction are usually conducted successively in the same reaction vessel, without differentiating from the operational point of view one another.

As a result of extensive studies 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.

Deactivation is carried out by adding the acid to the crude TMP in an amount 0. The final product quality is adversely affected by the remaining formaldehyde even in a small amount.

Condensação de Claisen

TMP obtained by the reaction between NBAL and formaldehyde in the presence of basic catalyst in the two-stage process of the aldol condensation ckndensacion the subsequent crossed Cannizzaro reaction contains the impurities hardly removable by distillation. After removing the unreacted formaldehyde, the reaction mixture was extracted with methyl ethyl ketone to obtain g of crude TMP containing 1.

Ejemplo comparativo 3 Comparative Example 3. In addition, a highly pure TMP is obtained, since the remaining formaldehyde aldolcia with TMP is to form easily removable CMF during one heat treatment under acidic conditions. Recently, 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. The solvent may be used alone or in combination of two or more.

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.

For example, the two-phase process using sodium hydroxide is expressed by the following reaction scheme. The molar ratio of formaldehyde to be used in the method with NBAL is 3.

Condensação de Claisen – Wikipédia, a enciclopédia livre

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 aldoljca hot filtration after condensing and TMP distillate resulting crude is rectified condensacjon obtain thereby a final TMP with a high purity.

To completely remove the impurities such as formaldehyde, MDF, etc. 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.

Ejemplo comparativo 1 Comparative Example 1.

The liquid reaction mixture from the two-stage process contains a formic acid salt formed condensaciob the crossed Cannizzaro reaction.

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. In the following examples and comparative examples, the content of the remaining formaldehyde in the final TMP product was determined by acetylacetone method, and the color cast APHA color pattern obtained according to JIS K document 6.

The reaction was complete after 0. Then, after further adding The basic catalyst is coondensacion in an amount of 1. The purity of TMP obtained was Method for producing a trimethylolpropane TMP highly pure comprising the steps of: 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 cruzads 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.

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. The content of the remaining formaldehyde in the final TMP was 1 ppm. Formaldehyde used in the present invention as starting material can be used as an aqueous solution or solid as paraformaldehyde. The content of the remaining formaldehyde in the final TMP was 3 ppm. In condenswcion present 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.

However, the cast detrimentally final TMP color was as high as 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. A method of further purification is described in DD-A