Wacker-chemie Gmbh

Gerhard Kunstle

Herbert Siegl

Hellmuth Spes

Klaus Vornehm

Herbert Jung

A process for stabilizing aqueous solutions of acetoacetamides which simultaneously results in the reduction of .beta.-aminocrotonic acid amide content. According to the process, to aqueous acetoacetamide solutions which have been prepared in a known manner by the reaction of diketene with ammonia or water-soluble primary or secondary aliphatic amines under basic conditions, sufficient amounts of diketene are added immediately after their preparation thereto at room temperature with vigorous stirring, to maintain a pH value of 6-7. The so obtained aqueous solutions of the acetoacetamides are not only substantially stable, but also especially pure since these solutions are neither contaminated by salt-like by-products nor by derivatives of .beta.-aminocrotonic acid amides.

Process for stabilizing aqueous solutions of acetoacetamides with

According to the invention, .alpha.-chloracetoacetamides, which is to be understood as including both .alpha.-chloro-N-monoalkylacetoacetamides and .alpha.-chloro-N,N-dialkylacetoacetamides, the alkyl radicals of which contain 1 to 3 carbon atoms, are produced by reacting the corresponding acetoacetamides with chlorine in aqueous solution at temperatures in the range of from -1.degree. C. to -25.degree. C. At a conversion of at least 95%, a selectivity of at least 97% and a yield of at least 95% of the theoretical yield, calculated on reacted acetoacetamide, are obtained.

Process for the manufacture of .alpha.-chloracetoacetamides

Process for the continuous preparation of acetoacetamides of the general formula

Process for the continuous preparation of acetoacetamides

Process for preparing cobalt(III)acetylacetonate comprising the steps of adding to cobalt(II)acetylacetonate in an organic solvent, at least the stoichiometric amount of acetylacetone, oxidizing with an excess of hydrogen peroxide, and separating the obtained cobalt(III)acetylacetonate by cooling and or concentration of the solution. The product obtained after drying is analytically pure and may be directly used as a catalyst for many chemical reactions, such as dimerizations, oligomerizations and polymerizations, oxidations and hydrogenations of olefins and many more.

Process for preparing cobalt(III)acetylacetonate

Process for making Dialkoxiboracetylacetonate containing mixtures of the general formula ##STR1## wherein R represents an aliphatic, straight or branched chain, saturated or unsaturated radical with 1-8 carbon atoms, by reacting boric acid trialkyl esters of the general formula B(OR).sub.3 with acetylacetone at temperatures from 10.degree.-150.degree. C, R having the same meaning as above. The mixtures are useful in many synthetic processes, e.g., for catalytic reactions and in the oxidation of hydrocarbons in combustion engines.

Process for making dialkoxiboracetylacetonate containing mixtures

A method for the purification of crude 2-aminothiazole comprising subjecting an aqueous melt of crude 2-aminothiazole to a vacuum distillation in the presence of a trialkyl borate and fractional solidification of the ensuing vapors.

Method for the purification of 2-aminothiazole

A process for preparing alkaliacetylacetonates from acetylacetone and alkali hydroxide, which consists of slowly adding an aqueous alkali hydroxide solution to an at least stoichiometric amount of acetylacetone dissolved in acetone, while stirring; dissipating the generated reaction heat by cooling, separating the precipitated alkaliacetylacetonates formed in the reaction, rinsing with acetone, and drying. The products of the reaction may be used in a large number of addition and condensation reactions as one of the reagents, and are sometimes effective as catalysts.

Process for preparing alkaliacetylacetonates

A process for preparing palladium(II)acetylacetonate having a low content in organically linked chlorine by reaction of acetylacetone with palladium dichloride or the complex tetrachloropalladinates derived therefrom, which comprises dissolving the starting palladium dichloride compound in hydrochloric acid, adding to the solution at least the stoichiometric amount of acetylacetone, stirring until the solution has become clear, adjusting the solution to a pH-value between 7 and 8 by drop-wise addition of an aqueous alkali hydroxide solution, separating the precipitated palladium(II)acetylacetonate from the solution, rinsing the palladium(II)acetylacetonate with water to free it from inorganic chloride, and drying. The products made by the process of the invention are effective catalysts in a variety of synthetic processes e.g. oxosyntheses, oligo and polymerizations, vinylization of aromatics and so on.

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Raitenhaslach, Germany

Gerhard Kunstle