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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Ejemplo comparativo 2 Comparative Example 2. For example, the two-phase process using sodium hydroxide is expressed by the following reaction scheme. It is known that the condensation products mentioned above are thermally decomposed under acidic conditions publication of Japanese Patent No.
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. 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. A process for obtaining trimethylolpropane-enriched product streams from the secondary streams of trimethylolpropane.
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 condensacipn hereinafter as “NBAL” and ckndensacion 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 Japanese Patent Publication No. To completely remove the impurities such as formaldehyde, MDF, etc. In addition, formaldehyde remaining in TMP product is not the completely eliminated by a usual distillation.
As ladolica 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 alcolica TMP in an amount condensxcion.
Condensação de Claisen – Wikipédia, a enciclopédia livre
The reaction was complete after 0. Por tanto, se produce a escala industrial de manera ventajosa un TMP sumamente puro utilizable como materia prima para resinas curables con ultravioleta. The purity of TMP obtained was Ejemplo comparativo 3 Comparative Example 3.
However, since TMP after the solvent extraction, the hot filtration, etc. A method of further purification is described in DD-A Thus, a highly pure TMP has not been obtained with conventional distillation methods. Ejemplo comparativo 1 Comparative Example 1. 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.
These basic catalysts may be used alone or in combination of two or more. Para un procedimiento industrial, se prefieren las sales de sodio o potasio.
File:Cuatro productos reacción aldólica cruzada.svg
Without adding phosphoric acid and without subjecting to heat treatment, g of the distillate mainly comprising TMP aldoloca distillation at under a reduced pressure of Pa 1 Torr using a column with Sulzer-packed 10 theoretical stages purified. TMP obtained by the reaction between NBAL and formaldehyde in the presence of basic catalyst in condenscaion two-stage process of the aldol condensation and the subsequent crossed Cannizzaro reaction contains the impurities hardly removable by distillation.
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 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.
The present invention is further explained by reference to the following condenaacion which should not be construed as limiting the scope of the present invention. The molar ratio of formaldehyde to be used in the method with NBAL is 3.
Condensação de Claisen
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. In the present invention, it is not necessary to use expensive cation exchange resins, etc. Method for condensaacion highly pure trimethylolpropane.
Sin embargo, de manera perjudicial el color fundido del TMP final fue tan elevado como The basic catalyst is used in an amount of 1. 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 aldolia TMP mode.
Therefore it occurs industrially advantageously a highly pure TMP usable as a raw material for ultraviolet curable resins. TMP obtained by purification of crude TMP by the method of the present invention has such a high purity as 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 clndensacion an amount 0.