JPH11269138A - Organic base producing agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new compound useful as an organic base precursor having the rapidity of producing a base at the time of heating compatible with the stability during the preservation. SOLUTION: This compound is represented by formula I [R<1> to R<4> are each H, an alkyl, an alkenyl, an aralkyl or an aryl; Z is a substituent group having a value of σ of >=0 when defined by the Hammett's equation; [(i)+(j)] is 3 and (i) is 1 or 2] or formula II (R<5> to R<10> are each same as R<1> to R<4> ), e.g. a compound represented by formula III. The compound represented by formula I is obtained by charging stearylamine, triethylamine and chloroform into a flask equipped with a stirrer, dropping 1.5 g of 1-chloro-2-methyl-2-propyl chloroformate thereinto under cooling with ice, continuing the stirring for 2 hr, then diluting the reactional solution with chloroform, washing the diluted reactional solution with water, dehydrating the washed solution, subsequently distilling off the chloroform under a reduced pressure and recrystallizing the prepared colorless powder from a mixed solvent of an ether with n-hexane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an organic base generator which generates a base by thermal energy.

[0002]

2. Description of the Related Art Organic bases are highly versatile reagents used in various reactions, for example, hydrolysis reactions, polymerization reactions, color reactions, oxidation-reduction reactions, neutralization reactions and the like, and constitute general products. In many cases, a base is incorporated.

A compound that generates a base by heating is called a base precursor, and this base precursor is used in various systems designed to react with a base generated by heating. Examples of such a system include a thermosensitive recording material, a photothermographic material, an anionic polymerizable adhesive, and formation of a coating film.

One of the most preferable uses of the base precursor is various image forming materials utilizing heat, for example, heat-sensitive recording materials, photothermographic materials and the like. In these materials, the base generated by heating reacts with other built-in chemical species to cause an image erasing reaction or an image forming reaction, so that the performance of the recording material greatly depends on the performance of the base precursor. The base precursor must produce the base rapidly at the lowest possible heating temperature while being stable during storage.

As typical base precursors, US Pat. No. 3,493,374 and British Patent No. 998949 are known.
No., U.S. Pat. No. 4,060,420, JP-A-59-168441, JP-A-59-180537,
JP-A-60-237443, JP-A-61-51139
JP-A-1-68746, JP-A-8-169870
And the salts of carboxylic acids and organic bases described in each of the above publications. All of these utilize the property that an organic base is released by decarboxylation of a carboxylic acid by heating.

On the other hand, JP-A-59-166943 discloses a system utilizing a reaction in which an organic base is released by Rossen rearrangement.

However, in any case, it has not been sufficiently satisfactory in terms of achieving both rapidity of base formation upon heating and stability during storage.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an organic base precursor having both rapidity of base generation upon heating and stability during storage.

[0009]

The object of the present invention has been attained by a compound represented by the general formula (1) or (2).

[0010]

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[0011]

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In the formulas (1) and (2), R ^{1 to} R ¹⁰ may be the same or different and each represents a hydrogen atom, an alkyl group, an alkenyl group, an aralkyl group, or an aryl group, and Z represents a Hammett's group. Σ greater than or equal to 0 when specified by the formula
Is a substituent having a value, i + j = 3 and i represents 1 or 2.

In the compound represented by the general formula (1) or (2), Z is a substituent having a σ value of 0 or more as defined by Hammett's formula. Preferred substituents include, for example, alkylcarbonyl, alkenylcarbonyl, aralkylcarbonyl, arylcarbonyl, alkyloxycarbonyl, alkenyloxycarbonyl, aryloxycarbonyl, aralkyloxycarbonyl, alkylsulfonyl, alkenylsulfonyl Groups, aralkylsulfonyl groups, arylsulfonyl groups, alkylsulfoxide groups, alkenylsulfoxide groups, aralkylsulfoxide groups, arylsulfoxide groups, halogen, nitro groups, and cyano groups.

In particular, alkylcarbonyl, alkenylcarbonyl, aralkylcarbonyl, arylcarbonyl, alkylsulfonyl, alkenylsulfonyl, aralkylsulfonyl, arylsulfonyl, alkylsulfoxide, alkenylsulfoxide, aralkylsulfoxide, aryl Substituents such as sulfoxide, halogen, nitro or cyano are more preferred.

In the compound represented by the general formula (1) or (2), R ^{1 to} R ¹⁰ are preferably a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 5 to 14 carbon atoms, An alkenyl group having 1 to 20 carbon atoms, 7 to 20 carbon atoms
Or a phenyl group, a naphthyl group, or a heteroaromatic ring.

The alkyl group, alkenyl group, aralkyl group and aryl group represented by R ^{1 to} R ¹⁰ may have a substituent, for example, an alkyl group, an alkenyl group,
Aryl group, alkoxy group, alkoxyalkyloxy group, alkenyloxy group, aralkyloxy group, aralkyloxyalkoxy group, aryloxy group, aryloxyalkoxy group, alkylcarbonyl group, alkenylcarbonyl group, aralkylcarbonyl group, arylcarbonyl group, alkyl Oxycarbonyl group, alkenyloxycarbonyl group, aryloxycarbonyl group, aralkyloxycarbonyl group, alkylcarbonyloxy group, alkenylcarbonyloxy group, aralkylcarbonyloxy group, arylcarbonyloxy group, alkylsulfonyl group, alkenylsulfonyl group, aralkylsulfonyl group , Arylsulfonyl, alkylsulfoxide, alkenylsulfoxide, aralkylsulfoxide, ant Rusuruhokishido group, a hydroxyl group, a halogen, a nitro group, or a substituent such as a cyano group may be mono- or polysubstituted.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific examples of the compound represented by the general formula (1) include the following (1-1) to (2-8), but the present invention is not limited thereto. is not.

[0018]

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[0019]

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[0020]

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[0021]

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The preferred amount of the base precursor of the present invention is, for example, the use of the base precursor of the present invention as a decoloring agent in a thermosensitive recording material provided with a thermosensitive coloring layer containing an electron-donating colorless dye and an electron-accepting compound. In this case, the weight of the electron-donating colorless dye contained in the thermosensitive coloring layer is 5%.
0% to 1000%. The base precursor is 1
You may mix and use two or more types.

[0023]

The present invention is not limited to a specific example of a method for producing the compound of the present invention, but the present invention is not limited thereto.

Example 1 Synthesis of exemplified compound (1-2). In a flask equipped with a stirrer, stearylamine 2.2
g, triethylamine 0.9 g, chloroform 30 ml
And 1.5 g of 1-chloro-2-methyl-2-propyl chloroformate was added dropwise under ice cooling. After continuing stirring for 2 hours, the reaction solution was diluted with chloroform, washed with water and dehydrated, and chloroform was distilled off under reduced pressure. The obtained colorless powder was recrystallized from a mixed solvent of ether and n-hexane. 1.5 g of colorless crystals were obtained. Melting point 68 [deg.] C.

Example 2 Synthesis of exemplified compound (1-7). In a flask equipped with a stirrer, stearylamine 3.5 was added.
g, triethylamine 1.3 g, chloroform 50 ml
Was added, and a solution of 4.4 g of 9-fluorenylmethylsuccimidyl carbonate dissolved in 20 ml of chloroform was added dropwise under ice cooling. After removing the ice bath and continuing stirring for 18 hours, the reaction solution was diluted with chloroform, washed with water and dehydrated, and then chloroform was distilled off under reduced pressure. The obtained colorless powder was recrystallized from a mixed solvent of chloroform and n-hexane to obtain 4.0 g of colorless needles. Melting point 98 [deg.] C.

Example 3 Synthesis of exemplified compound (1-8). 1.6 g of 2-hydroxyindane, 1.2 g of stearyl isocyanate, 1.0 g of triethylamine and 20 ml of ether were charged into a flask equipped with a stirrer, and the mixture was stirred at room temperature for 18 hours. The crystals were collected by filtration to obtain 2.0 g of colorless needles. Melting point 85.5 ° C.

Example 4 Synthesis of exemplified compound (1-11) 0.7 g of ethylene cyanohydrin, 3.0 g of stearyl isocyanate, 1.1 g of triethylamine and 20 ml of acetone were charged into a flask equipped with a stirrer, and the mixture was stirred at room temperature for 18 hours. This gave 2.3 g of colorless needles. Melting point 108 [deg.] C.

Example 5 Synthesis of exemplified compound (1-12). In a flask equipped with a stirrer, 0.9 g of 4-hydroxy-2-butanone, 3.0 g of stearyl isocyanate,
After stirring triethylamine (1.1 g) and acetone (20 ml) at room temperature for 18 hours, the resulting crystals were collected by filtration under reduced pressure to obtain 2.5 g of colorless needles. Melting point 104
° C.

Example 6 Synthesis of exemplified compound (2-3). 2. In a flask equipped with a stirrer, 1,3-dicyclohexyl-2- (2,4-dimethylphenyl) guanidine.
3 g, 2.2 g of triethylamine and 50 ml of tetrahydrofuran were charged, and a solution prepared by dissolving 2.6 g of 9-fluorenylmethyl chloroformate in 20 ml of tetrahydrofuran was added dropwise under ice cooling. After removing the ice bath and continuing stirring for 18 hours, the mixture was poured into 200 ml of water and extracted with ethyl acetate. The ethyl acetate layer was washed with a 10% aqueous citric acid solution, and after dehydration, ethyl acetate was distilled off under reduced pressure. The obtained colorless amorphous substance was purified by silica gel column chromatography, and as a colorless amorphous substance, Exemplified Compound 2-3 was obtained.
3.4 g was obtained.

Comparative Example 1 Synthesis of N-octadecylmethyl carbamate. In a flask equipped with a stirrer, 0.3 g of methanol, 3.0 g of stearyl isocyanate, 1.1 g of triethylamine and 20 ml of acetone were charged, and stirring was continued at room temperature for 18 hours. The resulting crystals were collected by filtration under reduced pressure. 2.5 g of colorless needles were obtained. 71.5 ° C.

Test 1 10 mmol of the base precursor was weighed into a flask,
Heated on 150 ° C. oil bath for 30 seconds. The product was isolated and the generated base was weighed to determine the yield. The results are shown in Table 1.

Test 2 10 mmol of the base precursor was weighed into a flask,
After standing at 60 ° C. for 18 hours, the generated base was isolated and the decomposition rate was determined. The results are shown in Table 1.

Test 3 Approximately 6 mg of the base precursor was accurately weighed, and thermogravimetric analysis was performed from room temperature to room temperature under a nitrogen atmosphere at a heating rate of 10 ° C./min using a 7 series thermal analysis system manufactured by Perkin Elmer.
The test was performed in the range of 50 ° C. Table 1 shows the base generation start temperature and base generation temperature.

[0034]

[Table 1]

[0035]

As is evident from Table 1, it has become possible to provide a base precursor having both quickness of base formation during heating and stability during storage.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C07C 279/18 C07C 279/24 279/24 317/18 317/18 C09K 3/00 K C09K 3/00 B41M 5/18 109

Claims (2)

[Claims] 1. An organic base generator represented by the following general formula (1). Embedded image (In the formula (1), R ¹ , R ² , R ³ and R ⁴ may be the same or different and each represents a hydrogen atom, an alkyl group, an alkenyl group, an aralkyl group or an aryl group, and Z is a Hammet's formula. Is a substituent having a sigma value of 0 or more when specified by, i + j = 3 and i represents 1 or 2.) 2. An organic base generator represented by the following general formula (2). Embedded image (In the formula (2), R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ may be the same or different and each represents a hydrogen atom, an alkyl group, an alkenyl group, an aralkyl group, or an aryl group. , Z is 0 or more σ as defined by Hammett's equation
Is a substituent having a value, i + j = 3 and i represents 1 or 2. )