CA2085151A1 - N,n'-diacetic acid-n'-cyanomethyl salts thereof and their preparation - Google Patents
N,n'-diacetic acid-n'-cyanomethyl salts thereof and their preparationInfo
- Publication number
- CA2085151A1 CA2085151A1 CA002085151A CA2085151A CA2085151A1 CA 2085151 A1 CA2085151 A1 CA 2085151A1 CA 002085151 A CA002085151 A CA 002085151A CA 2085151 A CA2085151 A CA 2085151A CA 2085151 A1 CA2085151 A1 CA 2085151A1
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- CA
- Canada
- Prior art keywords
- salts
- acid
- cyanide
- formaldehyde
- reaction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
- C11D3/16—Organic compounds
- C11D3/26—Organic compounds containing nitrogen
- C11D3/33—Amino carboxylic acids
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C255/00—Carboxylic acid nitriles
- C07C255/01—Carboxylic acid nitriles having cyano groups bound to acyclic carbon atoms
- C07C255/24—Carboxylic acid nitriles having cyano groups bound to acyclic carbon atoms containing cyano groups and singly-bound nitrogen atoms, not being further bound to other hetero atoms, bound to the same saturated acyclic carbon skeleton
- C07C255/25—Aminoacetonitriles
Abstract
ABSTRACT
A novel intermediate useful in the synthesis of ethylenediaminetriacetic acid (E-D3A) or its salts. A salt of N,N'-ethylenediaminediacetic acid (ED2AH2) 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), which is a useful intermediate in the production of ED3A. The nitrile in aqueous solutions may be spontaneously cyclized to form 2-oxo-1,4-piperazinediacetic acid (3KP) or salts thereof.
In the presence of excess base, salts of ED3A are formed in excellent yield and purity.
A novel intermediate useful in the synthesis of ethylenediaminetriacetic acid (E-D3A) or its salts. A salt of N,N'-ethylenediaminediacetic acid (ED2AH2) 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), which is a useful intermediate in the production of ED3A. The nitrile in aqueous solutions may be spontaneously cyclized to form 2-oxo-1,4-piperazinediacetic acid (3KP) or salts thereof.
In the presence of excess base, salts of ED3A are formed in excellent yield and purity.
Description
5 N.N -I)IA~ETIC ~ N ~CYANO~1ETHYI,. SALTS TI~EREOF. ANI) ~HE~
PREPARATION
BACKG~O~ F THE INVENTlO~l Ethylenediamine~riacetic acid (ED3A) or its salts (such as ED3ANa3) has applications in the field of chelating chemistry, and may be used as a starting material in the preparation of strong chelating polymers, oil soluble chelants, surfactants and o~hers.
Conventional routes for the synthesis of ethylenediaminetriacetic acid were achieved via its 15 N-benzyl derivative, which was subsequently hydrolyzed in alkaline solutions to ED3ANa3, thus avoiding cyclization to its 2-oxo-1,4-piperazinediacetic acid (3KP) derivative.
Syntheses attempted by both the alkaline condensation of chloroacetic acid with ethylenediarnine, and the carboxymethylation of the diamine with forrnaldehyde and sodium cyanide resulted in complex mixtures requiring complex e~traction techniques (e.g. almost 20 exclusive solubility of 3KP in boiling dimethylformamide, Can. 1. Chemistry 1970, 48(1), 163-175) to generate the desired product, and then in only relatively poor yield. In addition, conventional processes resulted in large quantities of by-product, such as ethylenediaminetetraacetic acid (ED4A). Where the by-products were especially objectionable, complicated blocking techniques were necessary in order to achieve a 25 relatively pure solution.
One exarnple of the synthesis of ethylenediamine-N,N,N -triacetic acid is shown in Chemlcal Abstraas 78, Vol. 71, page 451, no. 18369c, 1969. There it is disclosed that ethylenediarnine reacts with CIH2CCO2H in a 1:3 molar ratio in basic solution at 10C for 24 hours to form a mixture from which ethylenediamine-N,N,N-triacetic acid can be 30 separated by complexing the same with Co(IlI). llle resulting cobalt complexes can be ` isolated through ion exchange.
`
- : ~
' ' : ~ ' .
ll~e instant invcntion is direc(ed to a novel composi~ion of malter ~hat is useful as an hllermediate in uhe synlhesis of elhylenediaminelriace~ic acid or its sall~ in high conversiolls and excell~nt yield.
SU, 11~1ARY OF TIIE INVE~TION
S The problems of ~he prior art have becn overcome by ~he ins~ant invention, which provides a novel composition of matter useful as an in~ermediale in lhe synthesis of elhylenediaminetriacetic acid. Specifically, a mononitrile~iacid is formed by reacting a salt of N,N'-elhylenediaminediacetic acid (ED2AH2) with formaldehyde to form a stable 5-membered ring intermediate. The addition of cyanide across this cyclic material forms ethylenediamineN.N'-diaceticacid-N'-cyanomethylorsaltslhereof(themononitrile-diacid).
This nitrile in aqueous solutions may be spontaneously cyclized to form 3KP or salts thereof, which in the presence of excess base, forms salts of ED3A in excellent yield and purity.
ETAILED OE~SCRIPl ION OF THE INVENTION
Suitable salts of ethylenediaminediacetic acid useful as the starting material in the instant invention include alkali and alkaline earth metal salts, in particular, the sodium and potassium salts. For purposes of illustration, the sodium salt will be used, although it should be understood that other salts may be employed without departing from the spirit and scope of the invention. One suitab]e reaction scheme for thesynthesis of the mononitrile-diacid is the alkaline condensation of formaldehyde with N,N'-ethylenediamine disodium acetate to form a 5-membered ring structure, 1,3-bis(carboxymethyl)imidazolidine, and is illustrated as follows:
cc~,x, ( N ~ ~,X, N
N~/ CC~X. CH~O ~- (> . H~O
5 C~ <
,~ D ? ' ' `
~h~ . b . 2 . ` ' ~'' . ~. .:
' ' ' '' , ' ' ~ ~
`' ' ' "~' ' The above reac~ion may be carricd ou~ in the presence of additional base.
Suitablc bascs include alkali and alkaline e~rth metal hydro~ides, preferably sodium and ~x~tassium hydro~ide. Compound (I) is the bridged reaction product of E~DDANa(l 0-.2 o~ and formaldchyde, which the prcsent invcntor has found to be a slable S inlcrmcdia~c in ~he ED3A synthesis. Compound (I) is formed easily between 0 and 110C. The reaction proceeds quickly and forms readily a~ pH's greater than about 7.0 Preferably the temperature employed is about 0 to 65C, most preferably 15 to 65C, although temperatures higher than 65C are operable. ' Formaldehyde can be used in stoichiometric amounts, although it is preferred that a slight molar excess be 10 used, preferably 0.5%-2.0%. Preferably the concentration of the formaldehyde is 55%
or less in aqueous solution. Paraformaldehyde also can be used.
The second step in the reaction scheme is illustrated below:
< COO~,IX b < COc~x b N N H
( > ~HCN _ ( < . N/\C--N
cOOH~X b ca~X b ( 11 ) Mononiirile-diacid Compound (Il) is readily formed at temperatures between 0 and 110C. The reaction should be conducted at temperatures at or below the boiling point of the solution. Preferably the reaction is carried out at temperatures from about 0 to about 65C, most preferably about 15 to 65C to enhance the reaction rate. Suitable sources of cyanide include gaseous hydrogen cyanide, an aqueous solution of hydrogen 30 cyanide, or alkali metal cyanide such as sodium cyanide or potassium cyanide, etc.
The cyanide may be uscd in stoichiomelric amoun~s, allhough sligh~ molar e~cesses may be used, prcrerably 0 5% - ~.0%.
Compound (Il) is uscrul as an intermcdiate for the production of ED3A.
Spccifically, compound (Il) may be hydrolyzed to lhe monoamide-diacid compound S (111) (partially hydrolyzed mononi~rile diacid), which spon~neously cyclizes to 3KP.
Compound (IV) forms readily in the presence of a base such as alkali metal or alkaline earlh metal hydroxides. Preferably the base is NaOH. Mole ratios of < 3.~M base : IM ED2AH2 but preferably < 2.0 M base: IM ~D2AH2 are employed. Higher concentrations of base (i.e. > 3.0 M base: M ED2AH2) cause some 10 disproportionation of the dias~id mononitrile and some ED4A
(ethylenediaminetetraacetic acid) is formed, especially at temperatures > 65C. In particular, the concentration of ED4A is found to be in direct proportion to ~he amount of excess caustic employed, when high temperature reactions are conducted and high molar ratios of base are employed (> 2.0M base: IM ED2AH~), which may be lS attributed to the simultaneous hydrolysis of 3K~ and disproportionation of the mononitrile-diacid. When the mole ratio of base to ED2A is < 2.0, higher temperatures may be used. Also, in S~ep 111 ammonia is eliminated between an amide group and an imino group on the same molecule. However, at lower temperatures ( <
65C) higher amounts of base may be employed (> 2.0M) and hydrolysis of 20 compound (Il) can proceed directly to ED3A without cyclization.
< G~aX b r <~ < CX~HaX b ~ base/H2o /N H ¦ ~ ~
~N/\C--N I ~N/\CNHz j~ ~N ~ NH3 < C~X}H,Xb < COO~ b - -J < CCOH,Xb ` (111) (IV) .
.
:
The 3KPNa2 is then hydrolyzed by at leas~ the addition of I equivalent of caustic, preferably a 1 molar excess of caustic. This amounts to approximately 5%
weight cxcess (free) caustic in solution on a 40% EO3ANa3 solution. The solu~ion is boilcd undcr almospheric pressure to the desircd concenlralion. Preferably Ihe reaction S is carried out by raising the temperature from the temperature in the formation of compound (IV) reac~ion to the boil over a period from about 30 minutçs to about 6 hours, < COO~aXb < COOX
( )=0 (N H
~asa N /\ (~OX
COOH,,X b < COOX
X ., base cal;on ( V ) The resulting solutions typically give approximately 35~0% ED3ANa3, with approximately 2 % 3KPNa2 remaining as an unopened ringed structure. This corresponds to about a 94% conversion to ED3ANa3, with the remaining 6% of mass existing as 3KPNa2. Acidification of this mass to pH's < 6~0 to produce ED3AH3 is 20 not possible, as cyclization to 3KPH2 will eventually occur~
The foregoing synthetic scheme results in conversions to ED3ANa3 in excess of 90%, with the residual proportion being 3KPNa2 to give a total mass balance of virtually 100%. The reactions are tolerant to a wide pH range.
The following procedure to obtain ED2AH2 was for experimental purposes only.
Far less elaborate schemes for ~he produc~ion of ED2AH2 are possible. Any schemes known in the art can be employ~d for the production of ED2AH2 and its salts, and the instant invention is not to be limited by any particular scheme.
In the following examples, all batches were synthesized from EDDAH2 5 (98.20%) oblained by acidification of EDDANa2 to a pH of 5.50 with nitnc acid, while maintaining the temperature of the solution < 10C. The resultant slurry was filtered by means of a Buchner funnel with the vacuum provided by a water aspirator. The hlter cake was washed with approximately 7 liters of iced H2O. To enhance drying, the cake was then washed with approximately I liter of MeOH. The crystals were then 10 placed on I inch deep stainless steel trays, dried in a Stokes vacuum dryer, model 338F
at 40C. under a vacuum of 4 mm Hg, for 12 hours. Approximately 2 Kg of a white crystalline powder was recovered. Analysis of this powder showed it to be 98.2%
All batches were synthesized on a 0.5 liter scale. 88 g of ED2AH2 were 15 charged to a 500 ml conical flask and diluted with 180 mls of H2O. 50% caustic was used to obtain the sodium salt in the ratio required. This solution was stirred for 30 minutes, and then charged to a 1 liter 5-necked round ~onom flask. The conical flask was then washed with 20 mls. of H2O, and the washings transferred to the round bottom flask. The round bottom flask was equipped with a magnetic stirring bar, a 20 condenser (ethylene glycoVH2O ~ 0C.), A ~250C mercury thermometer, and a J-type thermocouple that provided a signal to a Love proportional controller, which maintained the temperature at the desired level were employed. A Glass-Col heating mantle controlled by the Love controller via a Powerstat variable autotransformer was used to heat the contents of the flask. 37% CH20 and 100% HCN were pumped at :
approximately I g/minute and O.SOg/minute, respectively, by an FMI micro metering pump at a setting of 0.5, via 1/8~ Teflon tubing to the flask. A 125 ml addition funnel equippeid with a Teflon metering valve, and a condenser with the same coolant as described above, was used as the reseirvoir for the reactants to be pumped. Table 1 5 shows the rcsults for the experiments conducted up to the spontaneous cyclization of monoamide-diacid after it has been hydrolyzed. The mononitrile-diacid was not isolated; however, it was identified by HPLC as being the precursor to 3KP. 3KP was more easily quantified by HPLC, and it is that compound which is quantitatively shown in Table 1. Table 2 shows results for ED3A produced for 9 conditions using the 10 compound of the instant invention.
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The data demons~rate that both mass balances and conversions to product are e1tcellent. ED3A was measured by copper(ll) salt titration, and 3KP was measured by high pressure liquid chroma~ography (HPLC). The final column in the Table I shows the mass balances for stage 3 (the formation of 3KP) of the reac~ion. The 9th column S in Table 2 shows the percent conversion to product bas~d on recyclization.
Recyclization was achieved by acidifying a sample of the reaction mass with HCI to a pH of 2Ø These samples were then allowed to stand in an oven at 40C overnight an then on a bench at room temperature for 2 days prior to analysis. This technique was employed to verify the titration results, ensuring that all product was recyclized 10 to 3KPH2. Mass balances are not as good as those that were titrated, and this may be attributed to HPLC error and dilution error, etc.
.
.
. . :
PREPARATION
BACKG~O~ F THE INVENTlO~l Ethylenediamine~riacetic acid (ED3A) or its salts (such as ED3ANa3) has applications in the field of chelating chemistry, and may be used as a starting material in the preparation of strong chelating polymers, oil soluble chelants, surfactants and o~hers.
Conventional routes for the synthesis of ethylenediaminetriacetic acid were achieved via its 15 N-benzyl derivative, which was subsequently hydrolyzed in alkaline solutions to ED3ANa3, thus avoiding cyclization to its 2-oxo-1,4-piperazinediacetic acid (3KP) derivative.
Syntheses attempted by both the alkaline condensation of chloroacetic acid with ethylenediarnine, and the carboxymethylation of the diamine with forrnaldehyde and sodium cyanide resulted in complex mixtures requiring complex e~traction techniques (e.g. almost 20 exclusive solubility of 3KP in boiling dimethylformamide, Can. 1. Chemistry 1970, 48(1), 163-175) to generate the desired product, and then in only relatively poor yield. In addition, conventional processes resulted in large quantities of by-product, such as ethylenediaminetetraacetic acid (ED4A). Where the by-products were especially objectionable, complicated blocking techniques were necessary in order to achieve a 25 relatively pure solution.
One exarnple of the synthesis of ethylenediamine-N,N,N -triacetic acid is shown in Chemlcal Abstraas 78, Vol. 71, page 451, no. 18369c, 1969. There it is disclosed that ethylenediarnine reacts with CIH2CCO2H in a 1:3 molar ratio in basic solution at 10C for 24 hours to form a mixture from which ethylenediamine-N,N,N-triacetic acid can be 30 separated by complexing the same with Co(IlI). llle resulting cobalt complexes can be ` isolated through ion exchange.
`
- : ~
' ' : ~ ' .
ll~e instant invcntion is direc(ed to a novel composi~ion of malter ~hat is useful as an hllermediate in uhe synlhesis of elhylenediaminelriace~ic acid or its sall~ in high conversiolls and excell~nt yield.
SU, 11~1ARY OF TIIE INVE~TION
S The problems of ~he prior art have becn overcome by ~he ins~ant invention, which provides a novel composition of matter useful as an in~ermediale in lhe synthesis of elhylenediaminetriacetic acid. Specifically, a mononitrile~iacid is formed by reacting a salt of N,N'-elhylenediaminediacetic acid (ED2AH2) with formaldehyde to form a stable 5-membered ring intermediate. The addition of cyanide across this cyclic material forms ethylenediamineN.N'-diaceticacid-N'-cyanomethylorsaltslhereof(themononitrile-diacid).
This nitrile in aqueous solutions may be spontaneously cyclized to form 3KP or salts thereof, which in the presence of excess base, forms salts of ED3A in excellent yield and purity.
ETAILED OE~SCRIPl ION OF THE INVENTION
Suitable salts of ethylenediaminediacetic acid useful as the starting material in the instant invention include alkali and alkaline earth metal salts, in particular, the sodium and potassium salts. For purposes of illustration, the sodium salt will be used, although it should be understood that other salts may be employed without departing from the spirit and scope of the invention. One suitab]e reaction scheme for thesynthesis of the mononitrile-diacid is the alkaline condensation of formaldehyde with N,N'-ethylenediamine disodium acetate to form a 5-membered ring structure, 1,3-bis(carboxymethyl)imidazolidine, and is illustrated as follows:
cc~,x, ( N ~ ~,X, N
N~/ CC~X. CH~O ~- (> . H~O
5 C~ <
,~ D ? ' ' `
~h~ . b . 2 . ` ' ~'' . ~. .:
' ' ' '' , ' ' ~ ~
`' ' ' "~' ' The above reac~ion may be carricd ou~ in the presence of additional base.
Suitablc bascs include alkali and alkaline e~rth metal hydro~ides, preferably sodium and ~x~tassium hydro~ide. Compound (I) is the bridged reaction product of E~DDANa(l 0-.2 o~ and formaldchyde, which the prcsent invcntor has found to be a slable S inlcrmcdia~c in ~he ED3A synthesis. Compound (I) is formed easily between 0 and 110C. The reaction proceeds quickly and forms readily a~ pH's greater than about 7.0 Preferably the temperature employed is about 0 to 65C, most preferably 15 to 65C, although temperatures higher than 65C are operable. ' Formaldehyde can be used in stoichiometric amounts, although it is preferred that a slight molar excess be 10 used, preferably 0.5%-2.0%. Preferably the concentration of the formaldehyde is 55%
or less in aqueous solution. Paraformaldehyde also can be used.
The second step in the reaction scheme is illustrated below:
< COO~,IX b < COc~x b N N H
( > ~HCN _ ( < . N/\C--N
cOOH~X b ca~X b ( 11 ) Mononiirile-diacid Compound (Il) is readily formed at temperatures between 0 and 110C. The reaction should be conducted at temperatures at or below the boiling point of the solution. Preferably the reaction is carried out at temperatures from about 0 to about 65C, most preferably about 15 to 65C to enhance the reaction rate. Suitable sources of cyanide include gaseous hydrogen cyanide, an aqueous solution of hydrogen 30 cyanide, or alkali metal cyanide such as sodium cyanide or potassium cyanide, etc.
The cyanide may be uscd in stoichiomelric amoun~s, allhough sligh~ molar e~cesses may be used, prcrerably 0 5% - ~.0%.
Compound (Il) is uscrul as an intermcdiate for the production of ED3A.
Spccifically, compound (Il) may be hydrolyzed to lhe monoamide-diacid compound S (111) (partially hydrolyzed mononi~rile diacid), which spon~neously cyclizes to 3KP.
Compound (IV) forms readily in the presence of a base such as alkali metal or alkaline earlh metal hydroxides. Preferably the base is NaOH. Mole ratios of < 3.~M base : IM ED2AH2 but preferably < 2.0 M base: IM ~D2AH2 are employed. Higher concentrations of base (i.e. > 3.0 M base: M ED2AH2) cause some 10 disproportionation of the dias~id mononitrile and some ED4A
(ethylenediaminetetraacetic acid) is formed, especially at temperatures > 65C. In particular, the concentration of ED4A is found to be in direct proportion to ~he amount of excess caustic employed, when high temperature reactions are conducted and high molar ratios of base are employed (> 2.0M base: IM ED2AH~), which may be lS attributed to the simultaneous hydrolysis of 3K~ and disproportionation of the mononitrile-diacid. When the mole ratio of base to ED2A is < 2.0, higher temperatures may be used. Also, in S~ep 111 ammonia is eliminated between an amide group and an imino group on the same molecule. However, at lower temperatures ( <
65C) higher amounts of base may be employed (> 2.0M) and hydrolysis of 20 compound (Il) can proceed directly to ED3A without cyclization.
< G~aX b r <~ < CX~HaX b ~ base/H2o /N H ¦ ~ ~
~N/\C--N I ~N/\CNHz j~ ~N ~ NH3 < C~X}H,Xb < COO~ b - -J < CCOH,Xb ` (111) (IV) .
.
:
The 3KPNa2 is then hydrolyzed by at leas~ the addition of I equivalent of caustic, preferably a 1 molar excess of caustic. This amounts to approximately 5%
weight cxcess (free) caustic in solution on a 40% EO3ANa3 solution. The solu~ion is boilcd undcr almospheric pressure to the desircd concenlralion. Preferably Ihe reaction S is carried out by raising the temperature from the temperature in the formation of compound (IV) reac~ion to the boil over a period from about 30 minutçs to about 6 hours, < COO~aXb < COOX
( )=0 (N H
~asa N /\ (~OX
COOH,,X b < COOX
X ., base cal;on ( V ) The resulting solutions typically give approximately 35~0% ED3ANa3, with approximately 2 % 3KPNa2 remaining as an unopened ringed structure. This corresponds to about a 94% conversion to ED3ANa3, with the remaining 6% of mass existing as 3KPNa2. Acidification of this mass to pH's < 6~0 to produce ED3AH3 is 20 not possible, as cyclization to 3KPH2 will eventually occur~
The foregoing synthetic scheme results in conversions to ED3ANa3 in excess of 90%, with the residual proportion being 3KPNa2 to give a total mass balance of virtually 100%. The reactions are tolerant to a wide pH range.
The following procedure to obtain ED2AH2 was for experimental purposes only.
Far less elaborate schemes for ~he produc~ion of ED2AH2 are possible. Any schemes known in the art can be employ~d for the production of ED2AH2 and its salts, and the instant invention is not to be limited by any particular scheme.
In the following examples, all batches were synthesized from EDDAH2 5 (98.20%) oblained by acidification of EDDANa2 to a pH of 5.50 with nitnc acid, while maintaining the temperature of the solution < 10C. The resultant slurry was filtered by means of a Buchner funnel with the vacuum provided by a water aspirator. The hlter cake was washed with approximately 7 liters of iced H2O. To enhance drying, the cake was then washed with approximately I liter of MeOH. The crystals were then 10 placed on I inch deep stainless steel trays, dried in a Stokes vacuum dryer, model 338F
at 40C. under a vacuum of 4 mm Hg, for 12 hours. Approximately 2 Kg of a white crystalline powder was recovered. Analysis of this powder showed it to be 98.2%
All batches were synthesized on a 0.5 liter scale. 88 g of ED2AH2 were 15 charged to a 500 ml conical flask and diluted with 180 mls of H2O. 50% caustic was used to obtain the sodium salt in the ratio required. This solution was stirred for 30 minutes, and then charged to a 1 liter 5-necked round ~onom flask. The conical flask was then washed with 20 mls. of H2O, and the washings transferred to the round bottom flask. The round bottom flask was equipped with a magnetic stirring bar, a 20 condenser (ethylene glycoVH2O ~ 0C.), A ~250C mercury thermometer, and a J-type thermocouple that provided a signal to a Love proportional controller, which maintained the temperature at the desired level were employed. A Glass-Col heating mantle controlled by the Love controller via a Powerstat variable autotransformer was used to heat the contents of the flask. 37% CH20 and 100% HCN were pumped at :
approximately I g/minute and O.SOg/minute, respectively, by an FMI micro metering pump at a setting of 0.5, via 1/8~ Teflon tubing to the flask. A 125 ml addition funnel equippeid with a Teflon metering valve, and a condenser with the same coolant as described above, was used as the reseirvoir for the reactants to be pumped. Table 1 5 shows the rcsults for the experiments conducted up to the spontaneous cyclization of monoamide-diacid after it has been hydrolyzed. The mononitrile-diacid was not isolated; however, it was identified by HPLC as being the precursor to 3KP. 3KP was more easily quantified by HPLC, and it is that compound which is quantitatively shown in Table 1. Table 2 shows results for ED3A produced for 9 conditions using the 10 compound of the instant invention.
'` '"" `" ' .
.~
..
' .
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~. . - .... . -- - . ... . .. - . - TAsG~ 1 2A8EE I c~omlnq d Ud~ I c I ~ Y. ~DA ~ U
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6 s 22~-1 So~600 02X IOIS2~1~r.~oY.41~% ~lo~$
t 22090 SO 2~00 0201os2r.2a29%SO~IY. afily~ ooo~r . ~ 21~7 5029~.0 022C O.~;Y.Z- I~r.~75Y. 2-~% ~2~2r.
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¦0 10 - IJô -<boll~d 0 21-J.22 S2.50%20.66Y.75.241t t~sY~ 0~.6J S
Il . 026~.100.1N701VIEDO/1 J5 oo0.24720CSY. o.oo% O OOo~s 10000% 100.00%
I I - I25~.10 ~S C~S ~S.O 0.2-7~ % 2 ~7%~.71Y. 41.01% 50.72Y
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12 . J 251.~1 500.0 0.2J~ #J.SO#12.-9#GJ60# 2J.-a# ~70as 12 2'7 5- SO 1-7.002J24J2Y.4.C70# 12.90# 7025# 70-J% 90.GO#
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16 . I ~-9.0a 6$ C S 1.0o.~o~ 12.-7# - 02~ ooor. -.02%
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10~00 0-062-22%~5251L000Y. ôS25#
17 O 450 70 1 9N~o6ulEDDl~ 7517 0O 91 1- ~7Y. 52 50Y. 000Y. 52 50Y.
~7 I -1~457~-C 75 -0 0-90 2066Y. 729~Y. ooo~ 729-S17 2 -0~5105C~120 75 9~0 0-00 2-2Gr. 0565S VOV% ~56SY.
~7 . ~ ~7 0~ 7S 2~9 00 ~72- 97% U 16S 0~0-. 00 16%
1~ 4 4-5 66 7S 12~ 0 0 -0~2C 2-Y.~2 C~Y. 000Y. 92 6~Y.
17 5 407 20 Doll ~loll 0 -0625 -1%S I--- 0001~ 0$ I--S
16 0$0 70 1 9N7.Cl UlEDDA 50 C10 0 0 -01 I xr. 4 00$ 000Y. ao c 1~ I -9 J6 50 C ~ ; v ~r. s O~Y
W CH21v 50 C l ~CS 00 0~ 2- D-% S ~2 ~L 0 0VY. ~S 9~`L
~ ~02 ~0 boll b~0 0 ~ô~27 a-%- 10~ 000Y. U 10%
~..
The data demons~rate that both mass balances and conversions to product are e1tcellent. ED3A was measured by copper(ll) salt titration, and 3KP was measured by high pressure liquid chroma~ography (HPLC). The final column in the Table I shows the mass balances for stage 3 (the formation of 3KP) of the reac~ion. The 9th column S in Table 2 shows the percent conversion to product bas~d on recyclization.
Recyclization was achieved by acidifying a sample of the reaction mass with HCI to a pH of 2Ø These samples were then allowed to stand in an oven at 40C overnight an then on a bench at room temperature for 2 days prior to analysis. This technique was employed to verify the titration results, ensuring that all product was recyclized 10 to 3KPH2. Mass balances are not as good as those that were titrated, and this may be attributed to HPLC error and dilution error, etc.
.
.
. . :
Claims (9)
1. A compound represented by the following formula:
wherein X and Y each represent hydrogen or an alkali metal or alkaline earth metal.
wherein X and Y each represent hydrogen or an alkali metal or alkaline earth metal.
2. A process for the preparation of a compound represented by the following formula:
wherein X and Y each represent hydrogen or an alkali metal or alkaline earth metal, comprising:
a. reacting formaldehyde with an alkali metal or alkaline earth metal salt of ethylenediaminediacetic acid; and b. reacting the product of step a with a cyanide source.
wherein X and Y each represent hydrogen or an alkali metal or alkaline earth metal, comprising:
a. reacting formaldehyde with an alkali metal or alkaline earth metal salt of ethylenediaminediacetic acid; and b. reacting the product of step a with a cyanide source.
3. The process of claim 2, wherein the reaction of formaldehyde and ethylenediamine dialkali metal acetate is conducted at a temperature from about 0° to about 65°C.
4. The process of claim 2, wherein the reaction of formaldehyde and ethylenediamine dialkali metal acetate is conducted at a temperature from about 15° to about 65°C.
5. The process of claim 2, wherein the reaction of step b is conducted at a temperature from about 0° to about 65°C.
6. The process of claim 2, wherein the reaction of step b is conducted at a temperature from about 15° to about 65°C.
7. The process of claim 2, wherein said formaldehyde is used in a slight molar excess.
8. The process of claim 2, wherein said cyanide source is used in a slight molar excess.
9. The process of claim 2, wherein said cyanide source is selected from the group consisting of hydrogen cyanide and alkali metal cyanide.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/806,032 US5177243A (en) | 1991-12-12 | 1991-12-12 | N,N'-diacetic acid-N'-cyanomethyl, salts thereof, and their preparation |
| US806,032 | 1991-12-12 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2085151A1 true CA2085151A1 (en) | 1993-06-13 |
Family
ID=25193153
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002085151A Abandoned CA2085151A1 (en) | 1991-12-12 | 1992-12-11 | N,n'-diacetic acid-n'-cyanomethyl salts thereof and their preparation |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US5177243A (en) |
| EP (1) | EP0546866B1 (en) |
| JP (1) | JP3272070B2 (en) |
| AU (1) | AU652499B2 (en) |
| CA (1) | CA2085151A1 (en) |
| DE (1) | DE69213183T2 (en) |
| ES (1) | ES2090531T3 (en) |
| NZ (1) | NZ245407A (en) |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4319935A1 (en) * | 1993-06-16 | 1994-12-22 | Basf Ag | Use of glycine-N, N-diacetic acid derivatives as complexing agents for alkaline earth and heavy metal ions |
| US5488130A (en) * | 1995-03-31 | 1996-01-30 | The Dow Chemical Company | Amino nitrile intermediate for the preparation of 2-hydroxypropyl iminodiacetic acid |
| DE19518986A1 (en) * | 1995-05-29 | 1996-12-05 | Basf Ag | Process for the preparation of glycine-N, N-diacetic acid derivatives by reacting glycine derivatives or their precursors with formaldehyde and hydrogen cyanide or iminodiacetonitrile or imindodiacetic acid with corresponding aldehydes and hydrogen cyanide in an aqueous acidic medium |
| US5621008A (en) * | 1995-10-27 | 1997-04-15 | Avon Products, Inc. | N-acyl-ethylene-triacetic acids |
| US5869441A (en) * | 1997-06-05 | 1999-02-09 | Lever Brothers Company, Division Of Conopco, Inc. | Bar compositions comprising novel chelating surfactants |
| US5801139A (en) * | 1997-06-05 | 1998-09-01 | Lever Brothers Company, Division Of Conopco, Inc. | Process for making bar compositions comprising novel chelating surfactants |
| TWI322828B (en) * | 2002-12-23 | 2010-04-01 | Alcon Inc | Use of multifunctional surface active agents to clean contact lenses |
| US7144512B2 (en) * | 2003-07-18 | 2006-12-05 | Bj Services Company | Method of reclaiming brine solutions using an organic chelant |
| US7674384B2 (en) * | 2003-07-18 | 2010-03-09 | Bj Services Company | Method of reclaiming brine solutions using an organic chelant |
| US7678281B2 (en) * | 2003-07-18 | 2010-03-16 | Bj Services Company | Method of reclaiming brine solutions using an organic chelant |
| US7172703B2 (en) * | 2003-07-18 | 2007-02-06 | Bj Services Co | Method of reclaiming a well completion brine solutions using an organic chelant |
| US8258334B2 (en) * | 2008-11-12 | 2012-09-04 | Irix Pharmaceuticals, Inc. | N-alkanoyl-N,N′,N′-alkylenediamine trialkanoic acid esters |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4704465A (en) * | 1985-11-22 | 1987-11-03 | Monsanto Company | Process for preparing ethylenediaminetetraacetonitrile |
-
1991
- 1991-12-12 US US07/806,032 patent/US5177243A/en not_active Expired - Lifetime
-
1992
- 1992-12-09 NZ NZ245407A patent/NZ245407A/en unknown
- 1992-12-11 AU AU30036/92A patent/AU652499B2/en not_active Ceased
- 1992-12-11 CA CA002085151A patent/CA2085151A1/en not_active Abandoned
- 1992-12-14 DE DE69213183T patent/DE69213183T2/en not_active Expired - Fee Related
- 1992-12-14 ES ES92311371T patent/ES2090531T3/en not_active Expired - Lifetime
- 1992-12-14 EP EP92311371A patent/EP0546866B1/en not_active Expired - Lifetime
- 1992-12-14 JP JP35356492A patent/JP3272070B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP3272070B2 (en) | 2002-04-08 |
| DE69213183D1 (en) | 1996-10-02 |
| JPH06172291A (en) | 1994-06-21 |
| NZ245407A (en) | 1995-03-28 |
| AU3003692A (en) | 1993-06-17 |
| EP0546866A3 (en) | 1993-09-08 |
| AU652499B2 (en) | 1994-08-25 |
| ES2090531T3 (en) | 1996-10-16 |
| US5177243A (en) | 1993-01-05 |
| EP0546866B1 (en) | 1996-08-28 |
| DE69213183T2 (en) | 1997-04-10 |
| EP0546866A2 (en) | 1993-06-16 |
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