Abstract: A process is proposed for the preparation of a crystalline L-MGDA trialkali metal salt by crystallization from an aqueous solution thereof which has been obtained by Strecker synthesis, starting from L-?-alanine, by reaction with formaldehyde and hydrocyanic acid to give L-?-alanine-N,N-diacetonitrile and subsequent alkaline saponification of the L-?-alanine-N,N-diacetonitrile to give the L-MGDA trialkali metal salt, wherein a temperature of 150° C. is not exceeded during the alkaline saponification.

Abstract: A process for preparing an aqueous solution of a methylglycine-N,N-diacetic acid trialkali metal salt at a high yield and purity by Strecker synthesis, the process including: reacting an aqueous solution containing ?-alanine with formaldehyde and hydrocyanic acid, to obtain ?-alanine-N,N-diacetonitrile in one reaction unit; and saponification of the ?-alanine-N,N-diacetonitrile with a base, to obtain the methylglycine-N,N-diacetic acid trialkali metal salt, wherein the ?-alanine is partially neutralized and the addition of formaldehyde and hydrocyanic acid are controlled such that a concentration of free hydrocyanic acid in the liquid reaction mixture at any time is limited such that secondary reactions that produce formaldehyde cyanohydrin, consecutive reactions of formaldehyde cyanohydrin, and the polymerization of hydrocyanic acid, only occur insofar as the specification requirements, such as nitrilotriacetic acid content and color, for methylglycine-N,N-diacetic acid trialkali metal salts are observed.

Abstract: Provided is a method for the production of aminodicarboxylic acid N,N-diacetic acids of formula (I), wherein X is independently hydrogen or an alkali metal and n is 1 or 2. Aminodicarboxylic acid-N,N-diacetic acids of high purity can be yielded. The method involves: a) reacting an aminodicarboxylic acid, with 0.8 to 1.2 mole equivalents of formaldehyde and with 0.8 to 1.2 mole equivalents of hydrocyanic acid; b) reacting the reaction products of a) with 0.8 to 1.2 mole equivalents of hydrocyanic acid and with 0.8 to 1.2 mole equivalents of formaldehyde; c) hydrolyzing in the reaction product obtained in b).

Abstract: A process is proposed for the preparation of a crystalline L-MGDA trialkali metal salt by crystallization from an aqueous solution thereof which has been obtained by Strecker synthesis, starting from L-?-alanine, by reaction with formaldehyde and hydrocyanic acid to give L-?-alanine-N,N-diacetonitrile and subsequent alkaline saponification of the L-?-alanine-N,N-diacetonitrile to give the L-MGDA trialkali metal salt, wherein a temperature of 150° C. is not exceeded during the alkaline saponification.

Abstract: A process for preparing an aqueous solution of a methylglycine-N,N-diacetic acid trialkali metal salt at a high yield and purity by Strecker synthesis, the process including: reacting an aqueous solution containing ?-alanine with formaldehyde and hydrocyanic acid, to obtain ?-alanine-N,N-diacetonitrile in one reaction unit; and saponification of the ?-alanine-N,N-diacetonitrile with a base, to obtain the methylglycine-N,N-diacetic acid trialkali metal salt, wherein the ?-alanine is partially neutralized and the addition of formaldehyde and hydrocyanic acid are controlled such that a concentration of free hydrocyanic acid in the liquid reaction mixture at any time is limited such that secondary reactions that produce formaldehyde cyanohydrin, consecutive reactions of formaldehyde cyanohydrin, and the polymerization of hydrocyanic acid, only occur insofar as the specification requirements, such as nitrilotriacetic acid content and color, for methylglycine-N,N-diacetic acid trialkali metal salts are observed.

Abstract: The present invention relates to a method for the production of aminodicarboxylic acid-N,N,diacetic acids of the general Formula I, wherein X independently of one another represents hydrogen or an alkali metal and n represents a number 1 or 2. Furthermore, the invention relates to aminodicarboxylic acid-N,N-diacetic acids of high purity. The inventive method comprises the following steps: A.) reacting an aminodicarboxylic acid of the general Formula II, wherein X and n have the aforementioned meanings, with 0.8 to 1.2 mole equivalents of formaldehyde and with 0.8 to 1.2 mole equivalents of hydrocyanic acid; b) reacting the reaction products of step a) with 0.8 to 1.2 mole equivalents of hydrocyanic acid and with 0.8 to 1.2 mole equivalents of formaldehyde; c) hydrolyzing in the reaction product obtained in step b).

Abstract: The invention relates to a process for preparing low-by-product, light-color methylglycine-N,N-diacetic acid tri(alkali metal) salt by alkaline hydrolysis of methylglycinediacetonitrile (MGDN), comprising the steps in the sequence (a) to (f): (a) mixing of MGDN with aqueous alkali at a temperature of ?30° C.; (b) allowing the aqueous alkaline MGDN suspension to react at a temperature in the range from 10 to 30° C. over a period of from 0.1 to 10 h to form a solution; (c) allowing the solution from step (b) to react at a temperature in the range from 30 to 40° C. over a period of from 0.1 to 10 h; (d) optionally allowing the solution from step (c) to react at a temperature in the range from 50 to 80° C. over a period of from 0.5 to 2 h; (e) optionally allowing the solution from step (c) or (d) to react at a temperature in the range from 110 to 200° C.

Abstract: The present invention relates to a process for preparing 3-cyano-3,5,5-trimethylcyclohexanone (isophoronenitrile) by reacting isophorone with hydrogen cyanide in the presence of a base as a catalyst to obtain a crude isophoronenitrile product, and subsequently distilling the crude isophoronenitrile product, with the addition before distillation of at least one specific sulfonic acid or specific carboxylic acid. In addition, the present invention relates to the use of a specific sulfonic acid or of a specific carboxylic acid as a neutralizing agent before distillation of a crude isophoronenitrile product which has been obtained by reacting isophorone with hydrogen cyanide in the presence of a base as a catalyst, in order to avoid precipitates in the neutralization of the base used as a catalyst with an acid.

Abstract: The invention relates to a process for preparing low-by-product, light-color methylglycine-N,N-diacetic acid tri(alkali metal) salt by alkaline hydrolysis of methylglycinediacetonitrile (MGDN), comprising the steps in the sequence (a) to (f): (a) mixing of MGDN with aqueous alkali at a temperature of ?30° C.; (b) allowing the aqueous alkaline MGDN suspension to react at a temperature in the range from 10 to 30° C. over a period of from 0.1 to 10 h to form a solution; (c) allowing the solution from step (b) to react at a temperature in the range from 30 to 40° C. over a period of from 0.1 to 10 h; (d) optionally allowing the solution from step (c) to react at a temperature in the range from 50 to 80° C. over a period of from 0.5 to 2 h; (e) optionally allowing the solution from step (c) or (d) to react at a temperature in the range from 110 to 200° C.

Abstract: The present invention relates to a process for preparing 3-cyano-3,5,5-trimethylcyclohexanone (isophoronenitrile) by reacting isophorone with hydrogen cyanide in the presence of a base as a catalyst to obtain a crude isophoronenitrile product, and subsequently distilling the crude isophoronenitrile product, with the addition before distillation of at least one specific sulfonic acid or specific carboxylic acid. In addition, the present invention relates to the use of a specific sulfonic acid or of a specific carboxylic acid as a neutralizing agent before distillation of a crude isophoronenitrile product which has been obtained by reacting isophorone with hydrogen cyanide in the presence of a base as a catalyst, in order to avoid precipitates in the neutralization of the base used as a catalyst with an acid.

Abstract: The invention relates to a continuous process, carried out in two steps, for the cyanoalkylation of compounds having one or more NH functions by reaction thereof with carbonyl compounds and hydrocyanic acid, in which the first step is carried out without pressure at a temperature which is below the boiling point of the reaction mixture.

Abstract: The present invention describes a process for preparing isophoronenitrile by adding HCN to isophorone. The catalyst used is CaO which has a BET surface area of >1.5 m2/g. The use of such a catalyst achieves high yields and selectivities.

Abstract: The present invention describes a process for preparing isophoronenitrile by adding HCN to isophorone. The catalyst used is CaO which has a BET surface area of >1.5 m2/g. The use of such a catalyst achieves high yields and selectivities.

Abstract: The invention relates to a continuous process, carried out in two steps, for the cyanoalkylation of compounds having one or more NH functions by reaction thereof with carbonyl compounds and hydrocyanic acid, in which the first step is carried out without pressure at a temperature which is below the boiling point of the reaction mixture.

Abstract: A process for preparing compounds of the formula IIb  where R is C6-C30-alkyl or C6-C30-alkenyl, which may additionally have upto 5 hydroxyl groups, formyl groups, C1-C4-alkoxy groups, phenoxy groups or C1-C4-alkoxycarbonyl groups as substituents and may be interrupted by upto 5 nonadjacent oxygen atoms, or alkoxylate groups of the formula —(CH2)k—O—(A1O)m—(A2O)n—Y where A1 and A2 are, independently of one another, 1,2-alkylene groups having 2 to 4 carbon atoms, Y is hydrogen, C1-C12-alkyl, phenyl or C1-C4-alkoxycarbonyl, and k is 1, 2 or 3, and m and n are each numbers from 0 to 50, and the total of m+n must be at least 4, by reacting iminodiacetonitrile with aldehydes of the formula R—CHO and HCN or alkali metal cyanides, the process being carried out a) in the absence of an organic solvent and in the presence of a Lewis or Brönsted acid, or b) in the presence or absence of an organic solvent and in the presence of an emulsifier, or c)

Abstract: The invention relates to a continuous process, carried out in two steps, for the cyanoalkylation of compounds having one or more NH functions by reaction thereof with carbonyl compounds and hydrocyanic acid, in which the first step is carried out without pressure at a temperature which is below the boiling point of the reaction mixture.

Abstract: A process for preparing compounds of the formula IIb 1

Abstract: A process for preparing compounds of the formula IIb  where R is C6-C30-alkyl or C6-C30-alkenyl, which may additionally have upto 5 hydroxyl groups, formyl groups, C1-C4-alkoxy groups, phenoxy groups or C1-C4-alkoxycarbonyl groups as substituents and may be interrupted by upto 5 nonadjacent oxygen atoms, or alkoxylate groups of the formula —(CH2)k—O—(A1O)m—(A2O)n—Y where A1 and A2 are, independently of one another, 1,2-alkylene groups having 2 to 4 carbon atoms, Y is hydrogen, C1-C12-alkyl, phenyl or C1-C4-alkoxycarbonyl, and k is 1, 2 or 3, and m and n are each numbers from 0 to 50, and the total of m+n must be at least 4, by reacting iminodiacetonitrile with aldehydes of the formula R—CHO and HCN or alkali metal cyanides, the process being carried out a) in the absence of an organic solvent and in the presence of a Lewis or Brönsted acid, or b) in the presence or absence of an organic solvent and in the presence of an emulsifier, or c)

Abstract: Glycine-N,N-diacetic acid derivatives I ##STR1## where R is unsubstituted or substituted alkyl, alkenyl, alkoxylate groups, phenylalkyl, phenyl, a heterocyclic ring or a radical of the formula ##STR2## where A is an alkylene bridge or a chemical bond, and M is hydrogen, alkali metal, alkaline earth metal, ammonium or substituted ammonium in the appropriate stoichiometric amounts,are prepared by reactingA) corresponding 2-substituted glycines or 2-substituted glycinonitriles or doubled glycines of the formula ##STR3## or doubled glycinonitriles of the formula ##STR4## or precursors of the glycine derivatives named as starting material with formaldehyde and hydrogen cyanide in aqueous medium at a pH of from 0 to 11 orB) iminodiacetonitrile or iminodiacetic acid with appropriate monoaldehydes of the formula R--CHO or dialdehydes of the formula OHC--A--CHO and hydrogen cyanide in aqueous medium at a pH of from 0 to 11and, where appropriate, subsequent hydrolysis of nitrile functionalities which are present, where

Abstract: Glycine-N, N-diacetic acid derivatives are prepared by reacting corresponding 2-substituted glycines, 2-substituted glycinonitriles, doubled glycines, or precursors of the glycine derivatives with formaldehyde and alkali metal cyanide. The reaction is conducted in an aqueous medium at a pH of 8 to 14. From 0, 5 to 30% of the amount of alkali metal cyanide required for the reaction are added to the glycine derivatives or precursors thereof Subsequently, the remaining amount of alkali metal cyanide and the formaldehyde are simultaneously metered in over a period of from 0.5 to 12 hours.