JPH0892226A - Production of n-methylated melamine derivative - Google Patents

Abstract

PURPOSE: To readily produce an N-methylated melamine derivative widely used as an intermediate of various fine chemicals, various resin materials or fire-resistant materials in high yield from an N-methylolated melamine derivative. CONSTITUTION: An N-methylolated melamine derivative having one or more metylolamino groups on carbon atoms in a ring are reduced in the presence of a catalyst of VIII group in the periodic table, preferably Ni, Pd or Pt catalyst and a hydrogen-containing gas at room temperature-500 deg.C, preferably 50-300 deg.C and a hydrogen partial pressure of 0.1-500kg/cm<2> , preferably 0.5-200kg/cm<2> to afford an N-methylated melamine derivative. The N-methylolated melamine derivative is preferably a mononuclear N-methylolated melamine derivative expressed by formula I (R<1> to R<6> are each H or methylol, except for all of H) and/or a polynuclear N-methylolated melamine derivative in which one or more of R<1> to R<6> in the compound of the formula I are the groups expressed by formula II (R<7> to R<11> are each H or methylol; (n)>=1).

Description

Detailed Description of the Invention

[0001]

The present invention relates to a novel process for producing N-methylated melamine derivatives by reducing various N-methylolated melamine derivatives in the presence of a catalyst of Group VIII of the periodic table and a hydrogen-containing gas. It is about. The substituted melamine derivative of the present invention is widely used as various fine chemical intermediates for agricultural chemicals, pharmaceuticals, dyes, paints, etc., as well as various resin materials, especially as aminoplast former components, or as flame retardant materials for thermoplastic polymers. It is a useful compound group.

[0002]

2. Description of the Related Art Various synthetic methods are known as a synthetic method of N-alkylated melamines.
(V)

[0003]

[Chemical 3]

(Where X is¹And X²Is diethylamino
Group, X³Is an ethylamino group, or X ¹, X²Is net
No group, X³Is an ethylamino group or a diethylamino group
Represent The compound of) is 2-chloro-1,3,5-tria.
A synthetic method by the reaction of a gin derivative with ethylamine was reported.
[Journal of America Chemical Society
Society (J. Amer. Chem. Soc), 73, 2984, 1
951]. General formula (V) (where X is¹, X²And X³
Represents an ethylamino group. ) Is 2,4,6-
Trimethylthio-1,3,5-triazine and ethylami
A synthetic method based on the reaction of benzene has been reported [Hemische Be
Chem Rer., 18: 2755, 1885
Year〕. General formula (V) (where X is¹Is an amino group, X²A
A mino group or an octylamino group, X³Is octylami
Represents a group. ) Is 2,4,6-triamino-
Reaction of 1,3,5-triazine with octylamine hydrochloride
A synthetic method by U.S.Pa.
tent), No. 2,228,161, 1941]. General formula
(V) (In the formula, X¹Is a piperidino group, X²And X³A
Represents a mino group. ) Compounds are cyanopiperidine and cyan
A synthetic method by the reaction of noguanidine has been reported [
Ger. Patent, 889,593, 195
3 years].

Further, various 2,4,6-substituted melamine derivatives synthesized from cyanuric chloride are used as flame retardants for thermoplastic polymers [JP-A-3-215564].
Some of the specific examples of the derivatives described in JP-A-3-215564 are shown below.

[0006]

[Chemical 4]

An example of the reaction of aminotriazines with carbonyl compounds such as aldehydes or ketones is represented by the reaction example of hydroxymethylation with melamine and an aqueous formalin solution under weak alkaline conditions [Journal of America.・ Chemical Society (J.Amer.C
hem.Soc), 69, 599, 1947]. Journal of America Chemical Society (J.Amer.C
(Shem. Soc), 73, 2984, 1954, often requires an equivalent amount or more of a condensing agent, and produces by-products such as salts which are often industrially problematic. See also Chem Ber., Vol. 18, 2755.
P., 1885 The synthesis method produces by-products such as sulfur compounds which are often problematic in industry. US Patent (USPa
Tent), No. 2,228,161, 1941 requires high temperature for the reaction, and the former produces ammonium chloride as a by-product. German Patent, 889,593
The synthesis method of No. 1953 is an excellent method in a laboratory because it uses a compound having a cyano group as a raw material, but it is not necessarily an industrially suitable method. Further, in both cases, there is a common point that a substituted amine or a derivative thereof which is not industrially inexpensive is used to carry out a substitution reaction or an addition reaction with a leaving group, which makes substituted triazines inexpensive. Is one of the reasons why we cannot supply it to

The reaction of aminotriazines with carbonyl compounds is 69, Journal of America Chemical Society (J. Amer. Chem. Soc), vol. 69, because the reactivity of the amino group on the triazine ring is low. Pp. 599, 19
As in 47 years, only the hydroxymethylation (methylolation) reaction due to the reaction of melamine and highly reactive formaldehyde is common, and the polynuclear body is easily dehydrated and condensed with other melamines during the reaction. The resulting reaction is known.

Therefore, there is no known method for producing N-methylated melamine via a methylolated mononuclear or polynuclear melamine compound.

[0010]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention As a result of diligent efforts to solve the above problems, the present inventors have found that industrially inexpensive mononuclear or polynuclear methylolated melamine derivatives are Partially or wholly reducing its methylol group in the presence of a Group VIII catalyst and a hydrogen-containing gas,
Moreover, it was completed with only water as a by-product.

The N-methylated melamine derivative obtained by this reaction remarkably inhibits the multimolecular association due to the intermolecular hydrogen bond inherent in aminotriazines, and at the same time improves the lipophilicity. The solubility in various solvents is improved, and at the same time, the melting point is also lowered, so that the compatibility with other organic compounds is also improved. Furthermore, the aminoplast resin using the N-methyl-N′-methylolmelamine derivative obtained by partially reducing the N-methylol group can also be imparted with flexibility by controlling the crosslink density. .

The object of the present invention is to provide a mononuclear or polynuclear N-methylolated melamine derivative which is industrially inexpensive and easily produced in the presence of a catalyst of Group VIII of the periodic table and a hydrogen-containing gas. , A group of useful compounds that can be widely used as fine chemical intermediates for various pesticides, pharmaceuticals, dyes, paints, etc., by partially or completely reducing the methylol group, and also as various resin materials and flame-retardant materials. Another object of the present invention is to provide a method for easily producing the N-methylated melamine derivative which is a high yield.

[0013]

That is, the present invention provides an N-methylolated melamine having at least one methylolamino group on a ring carbon atom in the presence of a catalyst of Group VIII of the Periodic Table and a hydrogen-containing gas. The present invention relates to a method for producing an N-methylated melamine derivative, which comprises reducing the derivative to obtain an N-methylated melamine derivative.

The present invention will be described in more detail below. The N-methylolated melamine derivative having at least one or more methylol groups, which is a raw material of the present invention, has the general formula (I).

[0015]

[Chemical 5]

[In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are each independently a hydrogen atom (provided that all are not hydrogen atoms), a methylol group (--CH ₂ OH group). } In the mononuclear N-methylol melamine derivative and / or the general formula (I), R ¹ , R ² ,
At least one of R ³ , R ⁴ , R ⁵ and R ⁶ has the general formula (II)

[0017]

[Chemical 6]

{Wherein R ⁷ , R ⁸ , R ⁹ , R ¹⁰ and R
¹¹ are each independently a hydrogen atom or a methylol group (-CH ₂ OH
Group) or formula (II), and n represents an integer of at least 1. } The polynuclear N-methylol melamine derivative represented by these. As shown above, in the present reaction, a mixture of mononuclear and polynuclear N-methylolmelamine having a plurality of N-methylol groups and having an average molecular weight of about 150 to 7,000, which is generally industrially produced, or Pure N-methylolmelamine can be directly subjected to the reaction, and all or part of the N-methylol group can be reductively converted to a methyl group.

In the reaction, the average molecular weight is 150 to 400 because of the reactivity of the raw materials and products and the ease of handling.
It is desirable to use a mixture of mononuclear and polynuclear N-methylolmelamines having an average molecular weight of 150.
It is desirable to use ~ 2000 mononuclear and polynuclear N-methylolmelamine mixtures. Regarding the synthesis of the raw material N-methylolmelamine derivative used in the present invention,
s-Triazines and Derivatives. Ed. by EM Smolin a
nd L. Rapoport. The Chemistry of Heterocyclic Comp
ounds., Inter-science Publishers Inc., NEW YORK.19
Details are given in 59.

Examples of the catalyst of Group VIII of the periodic table used in this reaction include iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum catalysts. For example, complex catalysts of these elements and supported catalysts. Etc. Among these elements, iron, nickel, ruthenium, rhodium, palladium and platinum catalysts are preferable, and nickel, palladium and platinum complexes and supported catalysts are particularly preferable. More specific examples of the catalyst will be given below.

As the iron catalyst, Raney iron or a complex of pentacarbonyl iron, dodecacarbonyltriiron, dichlorobis (triphenylphosphine) iron, tetracarbonyl (triphenylphosphine) iron, tricarbonylbis (triphenylphosphine) iron, etc. Examples include catalysts. Examples of the cobalt catalyst include Raney cobalt, and complex catalysts such as octacarbonyldicobalt, dodecacarbonyltricobalt, and chlorotris (triphenylphosphine) cobalt.

As the nickel catalyst, Raney nickel catalyst, solid silica and nickel-supporting silica, nickel-supporting alumina, nickel-supporting carbon, nickel-supporting diatomaceous earth, etc., dichlorobis (triphenylphosphine) nickel, tetrakis (triphenylphosphine) nickel,
Examples thereof include complex catalysts such as tetrakis (triphenylphosphite) nickel, nickel chloride, nickel oxide and the like.

As the ruthenium catalyst, ruthenium-supported silica, ruthenium-supported alumina, ruthenium-supported carbon and other supported catalysts, pentacarbonyl ruthenium, dodecacarbonyltriruthenium, tetrahydridododecacarbonyltetraruthenium, dihydrido (2 nitrogen) tris (triphenylphosphine) ) Ruthenium, dicarbonyltris (triphenylphosphino) ruthenium, tetracarbonyl (trimethylphosphite) ruthenium, pentakis (trimethylphosphite) ruthenium, tris (acetylacetonato) ruthenium, diacetatodicarbonylbis (triphenylphosphine) ruthenium Dichlorobis (chlorotricarbonyl) ruthenium, carbonylchlorohydridotris (triphenylphosphine) ruthenium, tetrahydo Ridotorisu (triphenylphosphine) ruthenium, acetate Tato hydride tris (triphenylphosphine) ruthenium, dichlorobis (acetonitrile) bis (triphenylphosphine) ruthenium, ruthenocene, bis (pentamethylcyclopentadienyl)
Ruthenium, dichloro (pentamethylcyclopentadienyl) ruthenium, chloro (cyclopentadienyl) bis (triphenylphosphine) ruthenium, hydride (cyclopentadienyl) bis (triphenylphosphine) ruthenium, chlorocarbonyl (cyclopentadienyl) ) Ruthenium, hydride (cyclopentadienyl)
(1,5-Cyclooctadiene) ruthenium, chloro (cyclopentadienyl) (1,5-cyclooctadiene) ruthenium, dihydridotetrakis (triphenylphosphine) ruthenium, cyclooctatriene (cyclooctadiene) ruthenium, chloro Hydride tris (triphenylphosphine) ruthenium, tricarbonylbis (triphenylphosphine) ruthenium, tricarbonyl (cyclooctatetraene) ruthenium, tricarbonyl (1,5-cyclooctadiene) ruthenium, dichlorotris (triphenylphosphine) ruthenium, etc. And complex catalysts of ruthenium chloride, ruthenium oxide, ruthenium black, and the like.

Examples of the palladium catalyst include Raney palladium, palladium-supported silica catalyst, palladium-supported alumina catalyst, palladium-supported carbon catalyst, palladium-supported barium sulfate catalyst, palladium-supported zeolite catalyst, palladium-supported silica / alumina catalyst, and other solid or supported catalysts. Dichlorobis (triphenylphosphine) palladium, dichlorobis (trimethylphosphine) palladium, dichlorobis (tributylphosphine) palladium, bis (tricyclohexylphosphine) palladium, tetrakis (triethylphosphite) palladium, bis (cycloocta-1,5-diene) palladium, tetrakis (Triphenylphosphine) palladium, dicarbonylbis (triphenylphosphine) palladium, carbonyltris (tri E nil phosphine)
Examples thereof include complex catalysts such as palladium, dichlorobis (benzonitrile) palladium and dichloro (1,5-cyclooctadiene) palladium, and palladium chloride and palladium oxide.

Examples of rhodium catalysts include rhodium-supported silica catalysts, rhodium-supported alumina catalysts, supported catalysts such as rhodium-supported carbon catalysts, chlorotris (triphenylphosphine) rhodium, hexadecacarbonylhexorhodium, dodecacarbonyltetrarhodium and dichlorotetracarbonylrhodium. , Hydrido tetracarbonyl rhodium, hydrido carbonyl tris (triphenylphosphine) rhodium, hydrido tetrakis (triphenylphosphine) rhodium, dichlorobis (cyclooctadiene) dirhodium, dicarbonyl (pentamethylcyclopentadienyl) rhodium, cyclopentadienyl Examples include complex catalysts such as bis (triphenylphosphine) rhodium and dichlorotetrakis (allyl) dirhodium, and rhodium chloride, rhodium oxide and the like.

As the platinum catalyst, a platinum-supported silica catalyst,
Platinum-supported alumina catalyst, supported catalyst such as platinum-supported carbon catalyst, dichlorobis (triphenylphosphine) platinum,
Dichlorobis (trimethylphosphine) platinum, dichlorobis (tributylphosphine) platinum, tetrakis (triphenylphosphine) platinum, tetrakis (triphenylphosphite) platinum, tris (triphenylphosphine) platinum, dicarbonylbis (triphenylphosphine) platinum, carbonyl Tris (triphenylphosphine) platinum, cis-bis (benzonitrile) dichloroplatinum,
Examples thereof include complex catalysts such as bis (1,5-cyclooctadiene) platinum, platinum chloride, platinum oxide (Adams catalyst), platinum black and the like.

The catalysts described above may be used alone or in combination. The amount of the Group VIII catalyst used in the periodic table is usually in the range of 0.00001 to 20 mol% and preferably in the range of 0.0001 to 10 mol% based on the N-methylolated melamine derivative of the general formula (I). Is good. A ligand may be added to the above catalyst, if necessary. Examples of the ligand include trimethylphosphine,
Triethylphosphine, tributylphosphine, triphenylphosphine, tris (paratolyl) phosphine,
Tris (2,6-dimethylphenyl) phosphine, diphenylphosphinobenzene-3-sulfonic acid sodium salt, bis (3-sulfonatophenyl) phosphinobenzene sodium salt, 1,2-bis (diphenylphosphino) ethane, 1, Monodentate and polydentate tertiary phosphines such as 3-bis (diphenylphosphino) propane, 1,4-bis (diphenylphosphino) butane, tris (3-sulfonatophenyl) phosphine sodium salt, triethylphosphite, tributyl Phosphite such as phosphite, triphenylphosphite, tris (2,6-dimethylphenyl) phosphite, triphenylmethylphosphonium iodide, triphenylmethylphosphonium bromide, triphenylmethylphosphonium chloride, triflate Nylallylphosphonium iodide, triphenylallylphosphonium bromide, triphenylallylphosphonium bromide, tetraphenylphosphonium iodide, tetraphenylphosphonium bromide, phosphonium salts such as tetraphenylphosphonium chloride, triphenyl phosphate, trimethyl phosphate, triethyl phosphate , Phosphate esters such as triallyl phosphate, unsaturated hydrocarbons such as cyclooctadiene and cyclopentadiene, nitriles such as benzonitrile and acetonitrile, and acetylacetone.

The amount of the ligand used is as shown in Table VIII of the Periodic Table.
The range is usually from 0.1 to 10,000 mol%, preferably from 10 to 5,000 mol% with respect to the group metal catalyst.
The reaction temperature is usually room temperature to 500 ° C., preferably 50 to
300 ° C is good. Although the reaction time depends on the reactivity of the N-methylolated melamine derivative of the general formula (I), it is usually 0.1.
-100 hours, preferably 0.5-50 hours.

This reaction proceeds even without solvent, but a solvent can be used if necessary from the viewpoint of operability and the like. The solvent is not particularly limited as long as it is inert to the reaction, for example, tetrahydrofuran, diethyl ether,
Diethylene glycol diethyl ether, ethers such as 1,4-dioxane, methanol, ethanol, 1-
Propanol, 2-propanol, 1-butanol, 2
-Alcohols such as butanol, isobutanol, 2-methyl-2-propanol, cyclohexanol, benzyl alcohol, benzene, toluene, xylene, mesitylene, cumene, chlorobenzene, o-dichlorobenzene, m-dichlorobenzene, p -Aromatic hydrocarbons such as dichlorobenzene and tetrahydronaphthalene, aliphatic hydrocarbons such as n-hexane, cyclohexane, n-octane and n-decane, methyl acetate, ethyl acetate, butyl acetate, ethyl propionate, benzoate Esters such as methyl acidate and ethyl benzoate, N, N-dimethylformamide,
Amides such as N, N-dimethylacetamide and N-methylpyrrolidone, 1,3-dimethylimidazolidinone,
Examples thereof include ureas such as N, N, N ′, N′-tetramethylurea, and water. These can be used alone or in combination.

This reaction is carried out in a pure hydrogen gas or a gas atmosphere containing hydrogen, and the pressure is 0.1 to
500 kg / cm ^2, preferably at a pressure of 0.5~200kg / cm ² gives good results. Further, in the case of the hydrogen-containing gas, various gases can be used as the diluent gas as long as they do not directly participate in the reaction. For example, nitrogen, argon, helium, etc. are generally used, but carbon dioxide, air, etc. can also be used, and ammonia, carbon monoxide, etc. are also used for the purpose of stabilizing products and catalysts. It When using these mixed gases, there is no problem as long as there is a hydrogen partial pressure necessary for the reaction, and the total pressure is 0.5 to 500 kg / c.
It is desirable to react at a pressure of m ² , preferably 1.0 to 300 kg / cm ² .

As a treatment method after completion of the reaction, after cooling the reaction solution, the unreacted N-methylolmelamine derivative is removed by a means such as filtration, and then the solvent is removed by distillation or the like, if necessary. After extracting the product as a water-organic solvent two-phase system, the reaction product can be purified and isolated by recrystallization, distillation, chromatographic separation, or the like. Further, the metal catalyst is a solid or supported catalyst by filtration or the like, and in the case of an organic metal complex catalyst, the solvent and the product are removed by distillation, recrystallization or the like, and the water-soluble ligand. When used, it can be separated, recovered, and reused in various forms such as a water-soluble metal complex in the aqueous layer by extraction operation.

The N-methylated melamine derivative obtained by reductively converting all or part of the N-methylol group of the raw material N-methylolmelamine of the present invention into the methyl group is as follows. Formula (III)

[0033]

[Chemical 7]

[In the formula, R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ are each independently a hydrogen atom (provided that all are not hydrogen atoms), a methyl group or a methylol group. (-CH ₂ OH
Group; provided, however, that all except a methylol group). } N-methylated melamine derivative represented by
Alternatively, in the general formula (III), R ¹² , R ¹³ , R ¹⁴ ,
At least one of R ¹⁵ , R ¹⁶ and R ¹⁷ has the general formula (IV)

[0035]

Embedded image

{In the formula, (in the formula, R ¹⁸ , R ¹⁹ , R ²⁰ , and R ²¹
And R ²² each independently represent a hydrogen atom, a methyl group, a methylol group (—CH ₂ OH group) or the formula (IV), and n represents an integer of at least 1 or more. } The polynuclear N-methylated melamine derivative represented by these.

[0037]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto. In addition, in the present Example, when a corresponding N-methylmelamine is produced using mononuclear N-methylolated melamine,
The product was separately synthesized as a standard (the synthetic method is US Pat. No. 2,430,462, J. Am. Chem. Soc., 73).
Vol. 2984, (1951), or Japanese Patent Laid-Open No. 3-2.
It was carried out according to No. 15564. ), A calibration curve was prepared from the isolated pure product and the internal standard substance, and the yield of each component in the reaction solution was accurately determined by the internal standard determination method by high performance liquid chromatography under the following conditions. I asked.

Analytical conditions for high performance liquid chromatography. (Method for quantifying mononuclear melamine derivative) Detection method; UV 230 nm column; GL Science Inertsil C ₈ 150 mm x
4.6 mmφ Flow rate: 1.0 ml / min Analytical temperature: 35 ° C Internal standard substance: Phthalic acid di (2-ethylhexyl) ester Also, in the case of polynuclear N-methylol melamine, both raw materials and products remain as a mixture. The weight average molecular weight was determined by GPC (gel permeation chromatography, eluent: N, N-dimethylformamide). Regarding the reaction, the N-methylol group content of both the raw material and the product was determined by chemical analysis (iodine method), and the chemical reduction reaction rate obtained from the difference between the values was defined as the yield. Moreover, from the fragment of the mass spectrum (ionization method: FD) of the raw material and the product,
It was confirmed that the N-methylol group was reduced to the N-methyl group depending on the reaction rate.

Example 1 A mononuclear N-methylolmelamine mixture (melamine: 40) was placed in a stainless steel autoclave having an internal volume of 100 mL.
% Formalin aqueous solution = 1: 4 (molar ratio), pH = 8.8
Synthesized in. N-methylol group content by chemical analysis (iodine method) 43.1% by weight. Average molecular weight: 216)
Was charged with 2.16 g (10 mmol), 408 mg of 5% activated carbon-supported Pd catalyst and 40 mL of ethanol, the inside of the reactor was sufficiently replaced with argon gas, and then hydrogen gas was introduced at an initial pressure of 50 kg / cm ² at room temperature. . Then, the temperature was raised to 180 ° C., and the reaction was performed for 8 hours while stirring.

After cooling, the pressure was released and the inside of the reactor was replaced with nitrogen gas, and then the reaction liquid was taken out. When the insoluble matter was filtered off, 0.79 g of an N-methylolmelamine mixture having an N-methylol group content of 39.8% was obtained. Further, when the liquid solution was chemically analyzed, the N-methylol group content was 0.3%.
As a result of quantitative analysis of each product by high performance liquid chromatography, 2,4,6-tris (methylamino)-
1,3,5-triazine 13.4%, 2-dimethylamino-4,6-bis (methylamino) -1,3,5-triazine 20.3%, 2,4-bis (dimethylamino) -6-methylamino-1,3,5-triazine is 1
3.9%, 2,4,6-tris (dimethylamino)-
Yield of 1,3,5-triazine was 13.8% (raw material N
-Methylolmelamine standard).

Example 2 A mononuclear N-methylolmelamine mixture (melamine: 40) was placed in a stainless steel autoclave having an internal volume of 100 mL.
% Formalin aqueous solution = 1: 4 (molar ratio), pH = 8.8
Synthesized in. N-methylol group content by chemical analysis (iodine method) 43.1% by weight. Average molecular weight: 216)
2.16 g (10 mmol) of Raney nickel catalyst 4
After charging 90 mg and 50 mL of ethanol and thoroughly replacing the inside of the reactor with argon gas, hydrogen gas was introduced at room temperature at an initial pressure of 50 kg / cm ² . Then, the temperature was raised to 150 ° C., and the reaction was carried out for 12 hours while stirring.

After cooling, the pressure was released and the inside of the reactor was replaced with nitrogen gas, and then the reaction liquid was taken out. When the insoluble matter was filtered off, 1.85 g of an N-methylolmelamine mixture having an N-methylol group content of 40.1% was obtained. Further, when the liquid solution was chemically analyzed, the N-methylol group content was 3.3%.
As a result of quantitative analysis of each product by high performance liquid chromatography, 2,4,6-tris (methylamino)-
1.4% 1,3,5-triazine, 3.6% 2-dimethylamino-4,6-bis (methylamino) -1,3,5-triazine, 2,4-bis (dimethylamino) −
6-methylamino-1,3,5-triazine is 2.6
%, 2,4,6-tris (dimethylamino) -1,3
5-Triazine was obtained in a yield of 1.7% (based on the raw material N-methylolmelamine). Example 3 A polynuclear N-methylolmelamine mixture (melamine: 40) was placed in a stainless steel autoclave having an internal volume of 100 mL.
% Formalin aqueous solution = 1: 2 (molar ratio), pH = 8, temperature 90 ° C. for methylolation reaction, part of the reaction solution is sampled in warm water, dissolved, and then the cloudiness temperature by cooling is 45 ° C. After the reaction was stopped, the product was spray dried with a spray dryer. N-methylol group content 22.0% by chemical analysis (iodine method). Average molecular weight by GPC (gel permeation chromatography):
850) was charged with 2.13 g (corresponding to 2.5 mmol), 408 mg of 5% activated carbon-supported Pd catalyst and 40 mL of methanol, and the inside of the reactor was sufficiently replaced with argon gas.
Hydrogen gas was introduced at room temperature at an initial pressure of 50 kg / cm ² . Then, the temperature was raised to 200 ° C., and the reaction was performed for 10 hours while stirring. After cooling, the pressure was released and the inside of the reactor was replaced with nitrogen gas, and then the reaction liquid was taken out in a slurry state. The residue obtained by distilling the solvent from the reaction solution was subjected to a chemical analysis (iodine method), and as a result, N-methylol group content of 15.5% was obtained.
2.06 g of methylol melamine mixture was obtained. This mixture had a weight average molecular weight of 830 by GPC, and it was confirmed by mass spectrum (ionization method: FD) that the N-methylol group was changed to an N-methyl group depending on the N-methylol group content. . From the results of this reaction,
It was found that 31.0% of the N-methylol groups in the raw material were converted into the corresponding N-methyl group (chemical reaction yield based on N-methylolmelamine of the raw material: 31.0%). Example 4 A polynuclear N-methylolmelamine mixture (melamine: 40) was placed in a stainless steel autoclave having an internal volume of 100 mL.
% Formalin aqueous solution = 1: 2 (molar ratio), pH = 8, reaction temperature 90 ° C., methylolation reaction was performed, part of the reaction solution was sampled in warm water, dissolved, and then cooled to a cloudiness temperature of 35 ° C. Sometimes after stopping the reaction, spray dried with a spray dryer. N-methylol group content 22.2% by chemical analysis (iodine method). GPC
(Average molecular weight by (gel permeation chromatography): 720) 1.80 g (corresponding to 2.5 mmol), 408 mg of Pd catalyst supporting 5% activated carbon and 40 mL of methanol were charged, and the inside of the reactor was sufficiently replaced with argon gas. After that, hydrogen gas was introduced at room temperature at an initial pressure of 50 kg / cm ² . Then, raise the temperature to 200 ° C and stir 1
The reaction was allowed for 0 hours.

After cooling, the pressure was released and the inside of the reactor was replaced with nitrogen gas, and then the reaction liquid was taken out in a slurry state. As a result of chemical analysis (iodine method) of the residue obtained by distilling off the solvent from the reaction solution, 1.71 g of an N-methylolmelamine mixture having an N-methylol group content of 14.2% was obtained.
This mixture has a weight average molecular weight of 690 by GPC,
Further, it was confirmed by mass spectrum (ionization method: FD) that the N-methylol group was changed to an N-methyl group depending on the N-methylol group content. From the results of this reaction, 39.0% of the N-methylol groups in the raw material were converted to the corresponding N-methyl group (chemical reaction yield based on N-methylolmelamine of the raw material: 39.0%). )It has been found.

[0044]

INDUSTRIAL APPLICABILITY According to the method of the present invention, various fine chemical intermediates such as various agricultural chemicals, pharmaceuticals, dyes, paints and the like, and various resin materials can be produced from N-methylol melamine derivatives under relatively mild reaction conditions. A mononuclear and polynuclear N-methylated melamine derivative, which is a useful compound group widely used as a flame-retardant material, can be easily produced in high yield.

The various mononuclear and polynuclear N-methylated melamine derivatives of the products obtained according to the invention are generally obtained as a mixture, which products can be further purified by conventional methods of separating organic compounds. It can be separated into various shapes and used for the various applications described above. Further, depending on the field of use (particularly in the case of a cross-linking agent for resins, flame retardants, modifying additives as plasticizers, etc.), the reaction mixture can be used as it is by mixing and resinizing without any particular separation. .

Further, many mononuclear and polynuclear N-methylated melamine derivatives obtained by this reaction have been relatively difficult to synthesize in the past, and also in terms of physical properties, water and various organic solvents are used. Many compounds are interesting in terms of their solubility in water, stability at high temperature, melting point, boiling point, basicity, etc., and their applications are expected to expand beyond those of conventional compounds.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yasuo Fukue 1 722, Tsuboi-cho, Funabashi-shi, Chiba Nissan Chemical Industry Co., Ltd. Central Research Laboratory

Claims (8)

[Claims] 1. An N-methylated melamine derivative is obtained by reducing an N-methylolated melamine derivative having at least one methylolamino group on a ring carbon atom in the presence of a catalyst of Group VIII of the periodic table and a hydrogen-containing gas. A method for producing an N-methylated melamine derivative, which comprises obtaining a derivative. 2. An N-methylolmelamine derivative having at least one or more methylolamino groups on a ring carbon atom is represented by the general formula (I): {Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are
Each independently represents a hydrogen atom (except when all are hydrogen atoms) and a methylol group (-CH ₂ OH group). } In the mononuclear N-methylol melamine derivative and / or the general formula (I), R ¹ , R ² , R ³ , R ⁴ and R
^At least one of ⁵ and R ⁶ has the general formula (II) {In the formula, R ⁷ , R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ each independently represent a hydrogen atom, a methylol group (—CH ₂ OH group) or the formula (II), and n is at least 1 or more. Represents an integer. } The method for producing an N-methylated melamine derivative according to claim 1, which is a polynuclear N-methylolated melamine derivative. 3. The N-methylol melamine according to claim 1, wherein the N-methylol melamine derivative represented by the general formula (I) has an average molecular weight of 150 to 7,000.
Process for producing methylated melamine derivative. 4. The N according to claim 1, wherein the catalyst of Group VIII of the periodic table is at least one catalyst selected from iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum catalysts. -A method for producing a methylated melamine derivative. 5. The N-methylated melamine derivative according to claim 8, wherein the catalyst of Group VIII of the periodic table is at least one catalyst selected from iron, nickel, ruthenium, rhodium, palladium and platinum catalysts. Production method. 6. A catalyst of Group VIII of the Periodic Table is nickel,
The method for producing an N-methylated melamine derivative according to claim 1, which is at least one catalyst selected from palladium and platinum catalysts. 7. Iron, cobalt, nickel, ruthenium,
The N- according to claim 1, wherein the rhodium, palladium, osmium, iridium and platinum catalysts are complex catalysts of the respective elements.
Process for producing methylated melamine derivative. 8. Iron, cobalt, nickel, ruthenium,
The N- according to claim 1, wherein a rhodium, palladium, osmium, iridium, platinum catalyst is a supported catalyst for each of the elements.
Process for producing methylated melamine derivative.