JPS611674A - Synthesis of 2-vinyl-4,6-diamino-s-triazine - Google Patents

Abstract

PURPOSE:A specific triazine adduct, as a starting substance, is subjected to heating in the presence of a polymerization inhibitor and a heat medium under reduced pressure to enable inexpensive and high-yield production of the titled compound which is used as a comonomer through simple operations in a practical scale. CONSTITUTION:2-[ beta-( 2'-Methylimidazolyl-1' )]-ethyl-4,6-diamino-S-triazineisocyanate of formula I, which is readily obtained from acrylonitrile, 2-methylimidazole and dicyandiamide and isocyanuric acid of formula IV, is heated, preferably together with a polymerization inhibitor such as sodium sulfide and a heating medium of particles or granules such as quartz sand, under reduced pressure of 5-20mm.Hg at 180-320 deg.C for 1hr to remove compounds of formulas III and IV as by-products and obtain the objective compound of formula II. The compound of formula III removed is collected in the form of aqueous solution and recovered by distillation under reduced pressure. The alkali salt of the compound of formula IV remains in the bottom of the distiller and is recovered.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for synthesizing 2-vinyl-4,6-diamino-S-)riazine (hereinafter referred to as V, T), and its purpose is to The objective is to provide a method that can be mass-produced at low cost.

The compound obtained by the method of the present invention is useful as a comonomer, and when diamino-3-') riazine is introduced into the side chain of the polymer, the softening point and male transition point of the polymer are significantly higher than that of the non-introduced polymer. It is known that the specific gravity also increases and the solubility changes significantly. [For example, Seo, Kakurai: Collection of Polymer Papers, 32, 308 (197
5); T, Seo, Abe, 11. Honma,
T, Kakurai: Polym, Prepn, +2
0,661 (1979)) Conventional Techniques Regarding the synthesis of V and T, several methods described below are already known. That is, the method of reacting biguanide with acrylic acid chloride (C, G, 0ver Berger et al.: J, 8, C, S, 80,988 (1
C11occ
hst company; Fr, 1. ! 'i63, 255 (1967
) ), 12-di(4',6'-diamino S-triazinyl-(211-cyclobutane) at 320° under reduced pressure
Method of heating to C [Asahi Kasei: Special Publication No. 46-35068]
, 2-β~Methoquinoethyl-4,6-diami2S-
) A method of heating riazine to 350°C in a nitrogen stream (S
KaIksticksLoff
Werke A,G,:Ger,'Offen,
2,135.881 (1973)) etc.

Problems to be Solved by the Invention However, each of the above-mentioned methods is not suitable for implementation on an industrial scale because the starting materials are expensive, the reaction operations are complicated, and the yield is low.

Means for solving the problem The starting material 2-(β-(
2'-Methylimidazole-1'))-ethyl-4,6
-Diamino S-1-Riazine isocyanuric acid adduct (hereinafter referred to as equivalent triazine adduct) was derived from the four considerations of acrylonitrile amide and isocyanuric acid in Japanese Patent Publication No. 56, 3.
It is a compound that can be easily obtained by the method described in No. 9314.

The reaction formula of the method of the present invention is as follows.

■V. T. The reaction yield starting from 2-methylimidazole isocyanuric acid and reaching the corresponding triazine adduct is good, and the reaction yield from the corresponding triazine adduct to V. T. The reaction that produces is easy to operate and has good yields.

Therefore, it can be said that the reaction of the present invention is suitable for implementation on an industrial scale.

Next, the embodiment of this reaction will be described.

The corresponding triazine adduct is mixed with a suitable polymerization inhibitor and a powder or granular heat transfer medium in a reaction vessel capable of maintaining a suitable reduced pressure at a reduced pressure of about 5 to 2 Qmmt1 g.
When heated at 80 to 320°C for an appropriate time, V. T. 2-methylimidazole and isocyanuric acid sublimate and adhere to the upper wall of the reaction vessel.

It is desirable that the upper chamber wall be air-cooled or water-cooled.

After collecting the deposits, wash them with alkaline aqueous solution and remove them.
Methylimidazole and isocyanuric acid were removed and the residue was reconsolidated with water to obtain the desired product V. T. get it.

Typical polymerization inhibitors used in this reaction include sulfur sulfide, potassium sulfide, hydroquinone, copper sulfate, and β-naphthylamine. Among them, sodium sulfide shows the most excellent polymerization prevention effect.

Typical powder or granular heat transfer media used in this reaction are as follows.

Quartz sand, sea sand, river sand, glass powder, silica powder, alumina powder, iron powder, copper powder, Shin@ powder, bronze powder, aluminum powder, zinc powder.

Each particle size above is . IIS500 to 2830μ (equivalent to US ryter method 32 to 7n+esh) is preferable.

It is desirable to carry out the reaction after thoroughly mixing at least the same weight of the medium with the corresponding triazine adduct.

The degree of reduced pressure is preferably higher, or about 5 mm/g is sufficient. The reaction time is within 1 hour.

The 2-methylimidazole removed by water washing is once collected in the form of an aqueous solution, and then subjected to vacuum distillation and recovered. On the other hand, the alkali isocyanuric acid salt remains at the bottom of the distiller and is recovered.

Next, we will discuss the properties of V and T.

m, p, 239-241°C (W). Soluble in hot water. Slightly soluble in hot methanol, hot ethanol, and hot acetone. Almost neutral. Dissolving it in hot water and adding azobisisobutyronitrile gives a polymer that is insoluble in hot water.

TLC (alumina and silica, EtOH): Rr=
o.

v KBr: 3340.3170.1680 (4th absorption"), 1655 (c4-' 2nd absorption), 1550 (1st absorption), 1460 (5th absorption), 1425 (3rd absorption), 1370.1265
．． 1130.985.960.835 (6th absorption) NM
R(d,-DMSO): δ6.76 (multiplet, 4H
); 6.35 to 6.45 (triple line, 2H); 5
．． 59-5.72 (quadruple line, IH) Elemental analysis value: 6%44.28.8%5.07, N%5
0.52 Next, the present invention will be specifically explained using examples.

34.8 g (0.1 mol) of crystals of the triazine adduct corresponding to the example were mixed with 1.2 g (0,005 mol) of Na,S.9aq.
After mixing well with an aqueous solution of 12 mN of water, the whole was dried under reduced pressure and used as a starting material. This is done in order to uniformly adhere the polymerization inhibitor to the corresponding triazine adduct crystals.

This raw material is mixed with 35g of quartz sand (particle size JIS approximately 1000μ) for approximately 10On+j! After mixing the two, the bottom of the flask was wrapped in a hood over an electric heater, heated under reduced pressure of 5 mmHg, and the flask internal temperature was maintained at 240° C. for 1 hour.

After cooling, the debris adhering to the upper part of the flask and the inner wall of the lug section was collected, and 50 mβ of 0.2N-Na011 aqueous solution was added thereto. After heating and stirring for a while, the insoluble matter was collected by filtration. (ygiV,T,) 100m j! reconsolidate with water, and the object V, T, (m, p, 239-24
1°C, TLC (silica EtOH, l, color development) RfO
,00-0.0t110.4 (yield 76%) was obtained.

Claims (1)

[Claims] (1) 2-{β-(2'-methylimidazolyl-1) shown by the structural formula▲Mathematical formulas, chemical formulas, tables, etc.▼
)}-Ethyl-4,6-diamino-S-triazine isocyanuric acid adduct is heated under reduced pressure in the presence of a polymerization inhibitor together with a powder or granular heat transfer medium.Structural formula ▲Mathematical formula, chemical formula There are tables, etc. ▼ Synthesis method of 2-vinyl-4,6-diamino-S-triazine.