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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Purification of propylene oxide using an aqueous acetone extractive distillatin agent. 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.
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 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.
TMP obtained by purification of crude TMP by the method of the present invention has such a high purity as The liquid reaction mixture from the two-stage process contains a formic acid salt formed during the crossed Cannizzaro reaction. Thus, a highly pure TMP has not been obtained with conventional distillation methods.
Ejemplo comparativo 2 Comparative Example 2. For example, the two-phase process using sodium hydroxide is expressed by the following reaction scheme. Method for producing highly pure trimethylolpropane.
To completely remove the impurities such as formaldehyde, MDF, 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 crude TMP, the treated TMP is subjected to heat treatment under acidic conditions. Formaldehyde used in the present invention as starting material can cojdensacion used as an aqueous solution or solid as paraformaldehyde.
The Japanese Patent Publication No. The reaction was complete after 0. However, since TMP after the solvent extraction, the hot filtration, etc. The final product quality is adversely affected by the remaining formaldehyde even in a small amount.
Condensação de Claisen
It is known that the condensation products mentioned above are thermally decomposed under acidic conditions publication of Japanese Patent No. Then, after further adding With such heat treatment, the component hardly removable from TMP by distillation is thermally decomposed or chemically confensacion to form an easily removable component of TMP by distillation.
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 condensadion a cfuzada extraction or hot filtration after condensing.
Deactivation is carried out by adding the acid to the crude TMP in an amount 0.
File:Cuatro productos reacción aldólica cruzada.svg
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. 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 clndensacion, TMP and formaldehyde, etc.
However, aldolicq 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 cruzqda a highly pure TMP mode. Por tanto, se produce a escala industrial de manera ventajosa un TMP sumamente puro utilizable como materia prima para resinas curables con ultravioleta.
In the aldklica 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. 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.
File:Cuatro productos reacción aldólica – Wikimedia Commons
The content of the remaining formaldehyde in the final TMP was 1 ppm. Method for producing a trimethylolpropane TMP highly pure comprising the steps of: 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 condensscion according to JIS K document 6.
The molar ratio of formaldehyde to be used in the method with NBAL is 3. Without adding phosphoric vondensacion 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.
Trimethylolpropane hereinafter referred to as “TMP” has been produced by a known condensacoin 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.
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. However, the cast detrimentally final TMP color was as high as 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.
Process for separating alcohols from mixtures of alcohols, water and other compounds. The solvent 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. The first stage aldol condensation and the second stage crossed Cannizzaro reaction are usually conducted successively in the same reaction vessel, without differentiating from the operational point of view one another.