US2768205A - Preparation of biguanides - Google Patents

Preparation of biguanides Download PDF

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Publication number
US2768205A
US2768205A US535509A US53550955A US2768205A US 2768205 A US2768205 A US 2768205A US 535509 A US535509 A US 535509A US 53550955 A US53550955 A US 53550955A US 2768205 A US2768205 A US 2768205A
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hydrochloride
temperature
biguanide
reaction mixture
formula
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US535509A
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Hechenbleikner Ingenuin
Donald W Kaiser
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Wyeth Holdings LLC
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American Cyanamid Co
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    • 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
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C279/00—Derivatives of guanidine, i.e. compounds containing the group, the singly-bound nitrogen atoms not being part of nitro or nitroso groups
    • C07C279/20—Derivatives of guanidine, i.e. compounds containing the group, the singly-bound nitrogen atoms not being part of nitro or nitroso groups containing any of the groups, X being a hetero atom, Y being any atom, e.g. acylguanidines
    • C07C279/24—Y being a hetero atom
    • C07C279/26—X and Y being nitrogen atoms, i.e. biguanides

Definitions

  • the present invention relates to a method of preparing biguanidcs which are capable of representation by the generic formula wherein R1 stands for an alkyl radical having from 1 to 18 carbon atoms, R2 stands for hydrogen or an alkyl radical having from 1 to 18 carbon atoms, and R3 and R4 stand for hydrogen, an aryl radical or an alkyl radical havingfrom 1 to 18 carbon atoms.
  • the biguanide compounds may be readily prepared by reacting in an inert solvent an alkylguanylchloroformamidine hydrochloride of the formula in which R1 and R have the meanings shown above, with a member of the group consisting of ammonia, a primary amine of the formula RsNHz and a secondary amine of the formula R3R4NH wherein R3 and R4 represent an aryl radical or an alkyl radical having from 1 to 18 carbon atoms. If necessary or desirable, the hydrochloride salt of the biguanide thus obtained is easily converted to the free base by treatment with an alkali metal hydroxide.
  • tetraethylguanylchloroforrnamidine hydrochloride is formed by reacting diethylcyanamide with hydrogen chloride at a temperature within the range of from 60 to 150 C.
  • the reaction may be illustrated as follows:
  • hydro- Amines typical of those capable of undergoing the reaction of the present invention are methylamine, dimethylamine, ethylamine, diethylamine, methylethylamine, methylisobutylamine, propylamine, dipropylamine, isopropylamine, ethylpropylarnine, butylamine, dibutylamine, amylamine, hexylamine, 2-ethylhexylamine, octylamine,
  • the optimum reaction temperature varies somewhat with the specific reactants employed, but in most reactions a temperature within the range of from about 10 C. to about C. is preferred.
  • Compounds which may be employed as solvents in the'process are benzene, toluene, acetonitrile, tetrahydrofurane, dioxane, water and the lower aliphatic monohydric alcohols such as the methyl, ethyl, propyl and butyl alcohols.
  • EXAMPLE 1 1 ,1 ,5,S-tetmmethylbiguanide A solution of 21.3 g. of tetramethylguanylchloroformamidine hydrochloride in 50 cc. of water was added slowly with stirring to .50 cc. of 28.6% aqueous ammonia. The temperature of the mixture rose rapidly to 65 C. The reaction mixture was then allowed to stand in an evaporating vessel at room temperature for 72 hours. The solid residue wa leached with boiling isopropanol. Evaporation of the filtrate gave 17 g. (88% yield) of the 1,1,5,5-tetramethylbiguanide hydrochloride which melted at 2122l5 C. The free base was formed by treating the hydrochloride salt with sodium hydroxide in aqueous solution.
  • EXAMPLE 3 1,5-di-t-butylbiguanide 26.9 g. of l,3-di-t-butylguanylchloroformamidine hydrochloride was added slowly with stirring to 50 cc. of 28.6% aqueous ammonia at 5-10 C. After standing at room temperature for one hour, the reaction mixture was filtered to recover the precipitated 1,5-di-t-butylbiguanide hydrochloride. After recrystallization from ethanol the hydrochloride salt melted at 230 C. The free base melted at 179180 C.
  • EXAMPLE 4 1 ,5 -di-t-butyl-4-amyl biguanide 10 g. of 1,3-di-t-butylguanylchloroformamidine hydrochloride was added slowly with stirring to a solution of 10 g. of n-amylamine in 20 cc. of acetonitrile maintained at about 5 C. After standing at room temperature for two hours, the reaction mixture was poured into 100 cc. of water and filtered to recover the precipitated 1,5-di-tbutyl-4-amylbiguanide hydrochloride. After recrystallization from ethanol the hydrochloride salt melted at 245-246 C. The free base was formed by treating the hydrochloride salt with potassium hydroxide in aqueous solution.
  • EXAMPLE 6 1 ,1 ,5 ,5 -tetramethyl-4-phenylbiguanide A mixture of 21.3 g. (0.1 mol) of tetramethylguanylchloroformamidine hydrochloride, 18.6 g. (0.2 mol) of aniline and 100 cc. of acetonitrile was heated for 10 minutes at reflux. The clear solution upon cooling to room temperature deposited 32 g. of solid material which was dissolved in 100 cc. of water and made basic with ammonia. The aniline which separated was extracted with benzene and the aqueous layer was made alkaline by the addition of sodium hydroxide. The precipitated biguanide (20 g.) was separated by filtration and recrystallized from cyclohexane. The white crystalline product melted at 8990 C.
  • the biguanides prepared by the method of the present invention are useful as tarnish inhibitors in detergent compositions utilized in the washing of household utensils such as tableware or silverware consisting of German silver and like alloys.
  • the quantity of the tarnish inhibitor to be used is generally less than 1% by weight of the detergent composition, and preferably from .05 to .5
  • the biguanides of Examples 2, 4, 5 and 6 above were tested as tarnish inhibitors by the following method: alloy bars (65% copper, 18% nickel, 17% zinc) A; x V2 x 2 /2 in size were cleaned with approximately 0.7 N nitric acid, rinsed with water and then acetone.
  • a commercial detergent composition consisting of approximately 50% sodium tripolyphosphate, 25-30% alkyl-aryl sulfonate, 1219% sodium sulfate and 34% sodium silicate was employed.
  • the alloy bar was immersed in 25 cc. of detergent solution (2.5 g. of
  • a method of preparing a biguanide of the formula Ni ?-N CN R: R2 wherein R1 represents an alkyl radical having from 1 to 18 carbon atoms, R2 represents a member of the group consisting of hydrogen and R1, and R3 and R4 are selected from the group consisting of hydrogen, an aryl radical and an alkyl radical having from 1 to 18 carbon atoms, which comprises reacting in an inert solvent an alkylguanylchloroformamidine hydrochloride of the formula in which R1 and R2 have the above meanings, with a member of the group consisting of ammonia, a primary amine of the formula RaNHz and a secondary amine of the formula R3R4NH wherein R3 and R4 represent members of the group consisting of an aryl radical and an alkyl radical having from 1 to 18 carbon atoms, and recovering the thus-formed biguanide from the reaction mixture.
  • the method which comprises reacting tetraethylguanylchloroformamidine hydrochloride with ammonia in an inert solvent at a temperature within the range of from 10 C. to 90 C., and recovering l,1,5,5-tetraethylbiguanide from the reaction mixture.
  • the method which comprises reacting tetramethylguanylchloroformamidine hydrochloride with dimethylamine in an inert solvent at a temperature within the range of from 10 C. to 90 C., and recovering 1,1,4,4,5,5-hexamethylbiguanide from the reaction mixture.
  • the method which comprises reacting tetramethylguanylchloroformamidine hydrochloride with aniline in an inert solvent at a temperature within the range of from 10 C. to 90 C., and recovering 1,1,5,5-tetramethyl-4- phenylbiguanide from the reaction mixture.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Wood Science & Technology (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Description

United States Patent PREPARATION OF BIGUANIDES 'Ingenuin Hechenbleikner, Adams, Mass, and Donald W.
Kaiser, Hamden, Comm, assignors to American Cyanamid Company, New York, N. Y., a corporation of Maine N0 Drawing. Application September 20, 1955, Serial No. 535,509
Claims. (Cl. 260-565) The present invention relates to a method of preparing biguanidcs which are capable of representation by the generic formula wherein R1 stands for an alkyl radical having from 1 to 18 carbon atoms, R2 stands for hydrogen or an alkyl radical having from 1 to 18 carbon atoms, and R3 and R4 stand for hydrogen, an aryl radical or an alkyl radical havingfrom 1 to 18 carbon atoms.
In accordance with the present invention, the biguanide compounds may be readily prepared by reacting in an inert solvent an alkylguanylchloroformamidine hydrochloride of the formula in which R1 and R have the meanings shown above, with a member of the group consisting of ammonia, a primary amine of the formula RsNHz and a secondary amine of the formula R3R4NH wherein R3 and R4 represent an aryl radical or an alkyl radical having from 1 to 18 carbon atoms. If necessary or desirable, the hydrochloride salt of the biguanide thus obtained is easily converted to the free base by treatment with an alkali metal hydroxide.
Methods of preparing the alkylguanylchloroformamidine hydrochlorides employed in the present process are disclosed in copending application, Serial No. 358,549, filed May 29, 1953, now abandoned, by Hechenbleikner, one of the present inventors.
For example, tetraethylguanylchloroforrnamidine hydrochloride is formed by reacting diethylcyanamide with hydrogen chloride at a temperature within the range of from 60 to 150 C. The reaction may be illustrated as follows:
1,3-dimethylguanylchloroformamidine hydrochloride 1,3-dipropylguanylchloroformamidine hydrochloride 2,768,205 Patented Oct. 23, 1956 hydro- Amines typical of those capable of undergoing the reaction of the present invention are methylamine, dimethylamine, ethylamine, diethylamine, methylethylamine, methylisobutylamine, propylamine, dipropylamine, isopropylamine, ethylpropylarnine, butylamine, dibutylamine, amylamine, hexylamine, 2-ethylhexylamine, octylamine,
'dioctylamine, decylarnine, dodecylamine, octadecylamine,
didodecylamine, dioctadecylamine, aniline, o-chloroaniline, p-bromoaniline, p-nitroaniline, N-methylaniline, N-ethylaniline, diphenylamine, Nmethyl-a-naphthylamine, a-naphthylamine, ,B-naphthylamine, di-B-naphthylamine, o-anisidine, p-phenetidine, N-methyl-p-pl1enetidine, the toluidines and xylidines.
In the present process .the optimum reaction temperature varies somewhat with the specific reactants employed, but in most reactions a temperature within the range of from about 10 C. to about C. is preferred. Compounds which may be employed as solvents in the'process are benzene, toluene, acetonitrile, tetrahydrofurane, dioxane, water and the lower aliphatic monohydric alcohols such as the methyl, ethyl, propyl and butyl alcohols.
The invention is further illustrated, but not limited, by the following examples:
EXAMPLE 1 1 ,1 ,5,S-tetmmethylbiguanide A solution of 21.3 g. of tetramethylguanylchloroformamidine hydrochloride in 50 cc. of water was added slowly with stirring to .50 cc. of 28.6% aqueous ammonia. The temperature of the mixture rose rapidly to 65 C. The reaction mixture was then allowed to stand in an evaporating vessel at room temperature for 72 hours. The solid residue wa leached with boiling isopropanol. Evaporation of the filtrate gave 17 g. (88% yield) of the 1,1,5,5-tetramethylbiguanide hydrochloride which melted at 2122l5 C. The free base was formed by treating the hydrochloride salt with sodium hydroxide in aqueous solution.
EXAMPLE 2 1,1,5,5-tetraethylbiguanide A solution of 13.4 g. of tetraethylguanylchloroformamidine hydrochloride in 50 cc. of methanol was added to 25 cc. of 28.6% aqueous ammonia at 5 C. The temperature-of the mixture rose quickly to 40 C. After standing at room temperature for one hour, the reaction mixture was poured into 200 cc. of water, and then made alkaline by the addition of sodium hydroxide. The precipitated biguanide was separated by filtration and recrystallized from hexane. The white crystalline product melted at 79-80" C.
EXAMPLE 3 1,5-di-t-butylbiguanide 26.9 g. of l,3-di-t-butylguanylchloroformamidine hydrochloride was added slowly with stirring to 50 cc. of 28.6% aqueous ammonia at 5-10 C. After standing at room temperature for one hour, the reaction mixture was filtered to recover the precipitated 1,5-di-t-butylbiguanide hydrochloride. After recrystallization from ethanol the hydrochloride salt melted at 230 C. The free base melted at 179180 C.
EXAMPLE 4 1 ,5 -di-t-butyl-4-amyl biguanide 10 g. of 1,3-di-t-butylguanylchloroformamidine hydrochloride was added slowly with stirring to a solution of 10 g. of n-amylamine in 20 cc. of acetonitrile maintained at about 5 C. After standing at room temperature for two hours, the reaction mixture was poured into 100 cc. of water and filtered to recover the precipitated 1,5-di-tbutyl-4-amylbiguanide hydrochloride. After recrystallization from ethanol the hydrochloride salt melted at 245-246 C. The free base was formed by treating the hydrochloride salt with potassium hydroxide in aqueous solution.
EXAMPLE 5 1,I,4,4,5,5-hexamethylbiguanide 213 g. of tetramethylguanylchloroformamidine hydrochloride was added slowly with stirring to 250 g. of a 40% aqueous solution of dimethylamine. The temperature of the mixture rose rapidly to about 40 C. After standing for 15 minutes, solid sodium hydroxide was added and the liquid separated into two phases. The organic phase was separated, dried over solid sodium hydroxide, and distilled under reduced pressure. The product, a colorless liquid, distilled at 115117 C./ 1.0 mm.
EXAMPLE 6 1 ,1 ,5 ,5 -tetramethyl-4-phenylbiguanide A mixture of 21.3 g. (0.1 mol) of tetramethylguanylchloroformamidine hydrochloride, 18.6 g. (0.2 mol) of aniline and 100 cc. of acetonitrile was heated for 10 minutes at reflux. The clear solution upon cooling to room temperature deposited 32 g. of solid material which was dissolved in 100 cc. of water and made basic with ammonia. The aniline which separated was extracted with benzene and the aqueous layer was made alkaline by the addition of sodium hydroxide. The precipitated biguanide (20 g.) was separated by filtration and recrystallized from cyclohexane. The white crystalline product melted at 8990 C.
The biguanides prepared by the method of the present invention are useful as tarnish inhibitors in detergent compositions utilized in the washing of household utensils such as tableware or silverware consisting of German silver and like alloys. The quantity of the tarnish inhibitor to be used is generally less than 1% by weight of the detergent composition, and preferably from .05 to .5 The biguanides of Examples 2, 4, 5 and 6 above were tested as tarnish inhibitors by the following method: alloy bars (65% copper, 18% nickel, 17% zinc) A; x V2 x 2 /2 in size were cleaned with approximately 0.7 N nitric acid, rinsed with water and then acetone. A commercial detergent composition consisting of approximately 50% sodium tripolyphosphate, 25-30% alkyl-aryl sulfonate, 1219% sodium sulfate and 34% sodium silicate was employed. The alloy bar was immersed in 25 cc. of detergent solution (2.5 g. of
detergent per 1500 cc. of water) containing 0.4% of the biguanide compound (based on the weight of the detergent). The temperature of the detergent solution was maintained at 43 C. and the period of immersion was 7 minutes. The bar was removed from the solution, rinsed with water and acetone, and stored under toluene for observation of tarnish film. A blank test with the detergent solution gave a heavy tarnish film on the alloy bar, whereas tarnishing was substantially diminished with the detergent solutions containing the biguanide compounds.
While the invention has been described with particular reference to specific embodiments, it is to be understood that it is not to be limited thereto but is to be construed broadly and restricted solely by the scope of the appended claims.
We claim:
1. A method of preparing a biguanide of the formula Ni ?-N=CN R: R2 wherein R1 represents an alkyl radical having from 1 to 18 carbon atoms, R2 represents a member of the group consisting of hydrogen and R1, and R3 and R4 are selected from the group consisting of hydrogen, an aryl radical and an alkyl radical having from 1 to 18 carbon atoms, which comprises reacting in an inert solvent an alkylguanylchloroformamidine hydrochloride of the formula in which R1 and R2 have the above meanings, with a member of the group consisting of ammonia, a primary amine of the formula RaNHz and a secondary amine of the formula R3R4NH wherein R3 and R4 represent members of the group consisting of an aryl radical and an alkyl radical having from 1 to 18 carbon atoms, and recovering the thus-formed biguanide from the reaction mixture.
2. The method of claim 1 in which the reaction is carried out at a temperature within the range of from about 10 C. to about C.'
3. The method which comprises reacting tetraethylguanylchloroformamidine hydrochloride with ammonia in an inert solvent at a temperature within the range of from 10 C. to 90 C., and recovering l,1,5,5-tetraethylbiguanide from the reaction mixture.
4. The method which comprises reacting tetramethylguanylchloroformamidine hydrochloride with dimethylamine in an inert solvent at a temperature within the range of from 10 C. to 90 C., and recovering 1,1,4,4,5,5-hexamethylbiguanide from the reaction mixture.
5. The method which comprises reacting tetramethylguanylchloroformamidine hydrochloride with aniline in an inert solvent at a temperature within the range of from 10 C. to 90 C., and recovering 1,1,5,5-tetramethyl-4- phenylbiguanide from the reaction mixture.
No references cited.

Claims (2)

1. A METHOD OF PREPARING A BIGUANIDE OF THE FORMULA
5. THE METHOD WHICH COMPRISES REACTING TETRAMETHYLGUANYLCHLOROFORMAMIDINE HYDROCHLORIDE WITH ANILINE IN AN INERT SOLVENT AT A TEMPERATURE WITHIN THE RANGE OF FROM 10* C. TO 90* C., AND RECOVERING 1,1,5,5-TETRAMETHYL-4PHENYLBIGUANIDE FROM THE REACTION MIXTURE.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3320229A (en) * 1963-08-26 1967-05-16 Stauffer Chemical Co Complexes of guanidines with completely halogenated acetones
WO2014208632A1 (en) 2013-06-28 2014-12-31 和光純薬工業株式会社 Base generator, base-reactive composition containing said base generator, and base generation method
WO2015111640A1 (en) 2014-01-24 2015-07-30 和光純薬工業株式会社 Borate-based base generator, and base-reactive composition comprising such base generator
KR20180034386A (en) 2015-07-24 2018-04-04 와코 쥰야꾸 고교 가부시키가이샤 A curable resin composition containing a base and / or a radical generator having acid resistance, and a base and / or a radical generator
TWI698416B (en) * 2015-09-11 2020-07-11 德商拜耳作物科學公司 Process for producing biguanidine salts and s-triazines

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3320229A (en) * 1963-08-26 1967-05-16 Stauffer Chemical Co Complexes of guanidines with completely halogenated acetones
WO2014208632A1 (en) 2013-06-28 2014-12-31 和光純薬工業株式会社 Base generator, base-reactive composition containing said base generator, and base generation method
KR20160025587A (en) 2013-06-28 2016-03-08 와코 쥰야꾸 고교 가부시키가이샤 Base generator, base-reactive composition containing said base generator, and base generation method
US10428014B2 (en) 2013-06-28 2019-10-01 Fujifilm Wako Pure Chemical Corporation Base generator, base-reactive composition containing said base generator, and base generation method
WO2015111640A1 (en) 2014-01-24 2015-07-30 和光純薬工業株式会社 Borate-based base generator, and base-reactive composition comprising such base generator
KR20160113149A (en) 2014-01-24 2016-09-28 와코 쥰야꾸 고교 가부시키가이샤 Borate-based base generator, and base-reactive composition comprising such base generator
US10100070B2 (en) 2014-01-24 2018-10-16 Fujifilm Wako Pure Chemical Corporation Borate-based base generator, and base-reactive composition comprising such base generator
KR20180034386A (en) 2015-07-24 2018-04-04 와코 쥰야꾸 고교 가부시키가이샤 A curable resin composition containing a base and / or a radical generator having acid resistance, and a base and / or a radical generator
US10428015B2 (en) 2015-07-24 2019-10-01 Fujifilm Wako Pure Chemical Corporation Acid-resistant base and/or radical generator, and curable resin composition containing said base and/or radical generator
TWI698416B (en) * 2015-09-11 2020-07-11 德商拜耳作物科學公司 Process for producing biguanidine salts and s-triazines

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