摘要:
A process for the preparation of phosphonomethylglycine in nearly quantitative yields which eliminates the use of a noble metal co-catalyst and its concomitant problems. The oxygen-containing gas is replaced with the much more chemically active hydrogen peroxide, which in combination with activated carbon, oxidizes the PMIDA to PMG in very high yield. The amount of oxidant allowed to react with PMIDA is a function of the concentration of oxygen in the gaseous reaction products, and is controlled by monitoring that concentration. In another embodiment, the oxidizing agent is an oxygen-containing gas. In either case, the concentration of oxygen in the gaseous reaction product is monitored to determine the end point of the reaction.
摘要:
Synthesis of ethylenediaminetriacetic acid (ED3A) or its salts is disclosed. A salt of N,N'-ethylenediaminediacetic acid (ED2AH.sub.2) is condensed with formaldehyde to form a stable 5-membered ring intermediate. The addition of cyanide across this cyclic material forms ethylenediamine N,N'-diacetic acid-N'-cyanomethyl or salts thereof (mononitrile-diacid). The nitrile in aqueous solutions may be spontaneously cyclized to form 2-oxo-1,4-piperazinediacetic acid (3KP) or salts thereof, which is the desired cyclic intermediate. In the presence of excess base, salts of ED3A are formed in excellent yield and purity. Alternatively, the starting material is ED2AH.sub.a X.sub.b, where x is a base cation, e.g., an alkali or alkaline earth metal, a is 1 to 2, and b is 0 to 1 in aqueous solutions. The reaction mixture also can be acidified to ensure complete formation of carboxymethyl-2-oxopiperazine (the lactam) prior to the reaction. Formaldehyde is added, essentially resulting in the hydroxymethyl derivative. On the addition of a cyanide source, 1-cyanomethyl-4-carboxymethyl-2-ketopiperazine (mononitrile diacid) or a salt thereof is formed. Upon the addition of any suitable base or acid, this material may be hydrolyzed to 3KP. The addition of a base will open this ring structure to form the salt of ED3A.
摘要:
A pesticidal composition including isocyanate capped high molecular weight diols, triols and polyols. A pesticide and water are combined with hydrophilic isocyanate end-capped prepolymers in order to significantly improve the efficacy of the pesticide. The liquid pesticidal compositions of the present invention can be prepared by simply mixing the various constituents. The order of addition can be used effectively to cap free isocyanate groups in the hydrophilic prepolymer.
摘要:
A process for producing iminodiacetonitrile (IDAN) from glycolonitrile and ammonia or its salt is disclosed. In the batch process, pH is controlled with the addition of ammonia or suitable acids. In the continuous process, glycolonitrile and ammonia are reacted in near stoichiometric amounts at a temperature from about 90.degree. C. to about 180.degree. C.
摘要:
Synthesis of ethylenediaminetriacetic acid (ED3A) or its salts is disclosed. A salt of N,N'-ethylenediaminediacetic acid (ED2AH.sub.2) is condensed with formaldehyde to form a stable 5-membered ring intermediate. The addition of cyanide across this cyclic material forms ethylenediamine N,N'-diacetic acid-N'-cyanomethyl or salts thereof (mononitrile-diacid). The nitrile in aqueous solutions may be spontaneously cyclized to form 2-oxo-1,4-piperazinediacetic acid (3KP) or salts thereof, which is the desired cyclic intermediate. In the presence of excess base, salts of ED3A are formed in excellent yield and purity. Alternatively, the starting material is ED2AH.sub.a X.sub.b, where x is a base cation, e.g., an alkali or alkaline earth metal, a is 1 to 2, and b is 0 to 1 in aqueous solutions. The reaction mixture also can be acidified to ensure complete formation of carboxymethyl-2-oxopiperazine (the lactam) prior to the reaction. Formaldehyde is added, essentially resulting in the hydroxymethyl derivative. On the addition of a cyanide source, 1-cyanomethyl-4-carboxymethyl-2-ketopiperazine (mononitrile diacid) or a salt thereof is formed. Upon the addition of any suitable base or acid, this material may be hydrolyzed to 3KP. The addition of a base will open this ring structure to form the salt of ED3A.
摘要:
A process for the preparation of phosphonomethylglycine in high yields is disclosed. In accordance with the process of the present invention, alkali metal IDA, such as disodium IDA, is reacted with a strong mineral acid, such as HCl, to convert the salt of IDA to IDA. The IDA is then converted to soluble IDA phosphite salt by the addition of phosphorous acid, and the alkali metal salt of the strong acid is precipitated. The phosphite salt of IDA is phosphonomethylated, such as by the addition of PCl.sub.3 and formaldehyde. Optionally, phosphorous trichloride can be hydrolyzed to provide the phosphorous acid source for phosphonomethylation of the phosphite salt.
摘要:
A process for recovering iminodiacetonitrile (IDAN) values from an aqueous IDAN solution comprising: (a) extracting the aqueous IDAN solution with methylene chloride to dissolve a portion of IDAN in the methylene chloride to form a methylene chloride solution of IDAN; and (b) separating and recovering the IDAN values from the methylene chloride.In an alternative embodiment the IDAN values can be separated from the methylene chloride solution of IDAN by extracting the methylene chloride solution with an aqueous alkali metal hydroxide solution to form water-soluble dialkali metal iminodiacetate (IDAM.sub.2 wherein M is an alkali metal cation) which remains in the aqueous alkali metal hydroxide solution. The IDAM.sub.2 can be recovered from the alkali metal hydroxide solution by conventional methods (e.g., by treating with a strong acid to precipitate iminodiacetic acid (IDA)).Each extraction (the extraction with methylene chloride and the extraction with aqueous alkali metal hydroxide solution) can be conducted as a batchwise extraction or as a continuous counter-current extraction.