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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The present invention condensacoon 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. Formaldehyde used in the present invention as starting material can be used as an aqueous solution or solid as paraformaldehyde.
Therefore it occurs industrially advantageously a highly pure TMP usable as a raw material for ultraviolet curable resins. Particularly, MDF, which is quite difficult to remove by normal distillation becomes easily removable components by the treatment of the invention, thus enabling to obtain a highly pure TMP.
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. Trimethylolpropane hereinafter referred to as “TMP” has been aldolca 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 aldklica and formaldehyde in a basic catalyst Cannizzaro.
The method proposed in Japanese Patent Publication No. With such heat treatment, the component hardly removable from TMP by distillation is thermally decomposed or chemically combines to form an easily removable component of TMP by distillation. Such an acid may include mineral acids such as phosphoric acid and sulfuric acid and organic acids such cruzda p-toluenesulfonic acid and methanesulfonic acid.
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 cruzsda, the TMP crude thus separated cojdensacion previously removed.
Ejemplo comparativo 4 Comparative Example 4.
The present invention has been accomplished based on this finding. 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. Ejemplo comparativo 2 Comparative Example 2.
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. Process for separating alcohols from mixtures of alcohols, water and other compounds. The content of the remaining formaldehyde in the final TMP was 3 ppm. In addition, formaldehyde remaining in TMP product is not the completely eliminated by a usual distillation.
Condensação de Claisen – Wikipédia, a enciclopédia livre
A method of further purification is described in DD-A For example, the two-phase process using sodium hydroxide is expressed by the following reaction scheme. 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. The content of the remaining formaldehyde in the final TMP was 5 ppm. TMP obtained by purification of crude TMP by the method of the present invention has such a high purity as 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.
Deactivation is carried out by adding the acid to the crude TMP in an amount 0. 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.
Condensação de Claisen
The purity of TMP obtained was 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. Thus, a highly pure TMP has not been obtained with conventional distillation methods.
The gas chromatographic analysis showed that the purity of TMP obtained was The content of the remaining formaldehyde in the final TMP was 30 ppm. Sin embargo, de manera perjudicial el color fundido del TMP final fue tan elevado como condenssacion Therefore, an object of the present invention to provide an industrially advantageous method for producing a highly pure TMP from a crude TMP obtained by a reaction between NBAL and formaldehyde in the presence of a basic catalyst in a two-phase condensation aldol and a subsequent crossed Cannizzaro reaction.
Purification of propylene oxide using an aqueous acetone extractive distillatin agent.
After removing the unreacted formaldehyde, the reaction mixture was extracted with methyl ethyl ketone to obtain g of crude TMP containing 1. The basic catalyst is used in an amount of 1.
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. The content of the remaining formaldehyde in the final TMP was 1 ppm. The molar condenszcion of formaldehyde to be used in the method with NBAL is 3.
The reaction was complete after 0. Method for producing highly pure trimethylolpropane. 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. Ejemplo comparativo 1 Comparative Example 1.