JPS5933595B2 - Method for producing spiropyran compounds - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a novel spiropyran compound that develops color under the action of light, heat, pressure or an electron-accepting substance.

5. As a method for producing spiropyran compounds, the method of reacting a salicylaldehyde derivative with an active methyl compound is generally known, but when it comes to producing a spiropyran derivative with a unique structure, it becomes difficult to synthesize the corresponding active methyl compound, and eventually This manufacturing method is disadvantageous in practice because it is expensive.

By the way, nitrile oxide and nitrile imine are
1 for double bonds such as -C(,]C-S and)C-N-
・3-dipole cyclization reaction (cyclodipolarad
dition) to do “Angew.chem”
．． Huisgen, L. Dan, 604-637. What you will understand from reading this review is that this cyclization reaction is actually overwhelmingly applied to ':, C-C(;
This suggests that the reaction to C=N- (S and ) is relatively less likely to occur than ', C-C. s or', C=N-
They came up with the idea of producing the target spiropyran compound by using a coumarin derivative with two types of double bonds as one of the reactants and using this cyclization reaction, but the success of this production was completely agnostic. It was hot.

This is because it was predicted that the reaction would occur preferentially to Cc (in the same molecule), and the desired compound would not be produced, or even if it was produced, the yield would be quite low. However, in Experiment 1, The results were completely unexpected.

This is because nitrile oxide and nitrile imine are present in the molecule] C=C (much more preferentially than] C-S and
This is because the target spiropyran compound was obtained in good yield by reacting with CN-. What was also unexpected was that this spiropyran compound exhibited excellent performance as a coloring agent that develops color under the action of light, heat, pressure, or an electron-accepting substance. Therefore, the first object of the present invention is to provide a novel spiropyran compound, and the second object is to provide a novel spiropyran compound.
An object of the present invention is to provide a method for producing a spiropyran compound useful for.

The above object of the present invention is to produce a spiropyran compound represented by the general formula (■) by subjecting the compound represented by the general formula (1) and the compound represented by the general formula (■) to a dipolar cyclization reaction. It is achieved by doing so.

General formula (1) [wherein z is S or NR1; R1 is an alkyl group (preferably 1 to 18 carbon atoms; for example, methyl, ethyl, propyl, butyl, octyl, tetradecyl octadecyl, etc.), an aralkyl group (preferably has an alkyl residue having 1 to 4 carbon atoms; for example, benzyl, phenethyl, diphenylmethyl, etc.) or an aryl group (for example, phenyl, naphthyl, substituted phenyl, substituted naphthyl, etc.; substituents include methyl, ethyl, propyl, Alkyl groups such as butyl; chlorine, bromine, iodine, fluorine, etc.
・Rogen atom; Nitro group; Alkoxy group such as methoxy, ethoxy, propoxy, butoxy; Amino group such as amino, methylamino, diethylamino; Aralkyloxy group such as benzyloxy); Ring A is a benzene ring or naphthalene ring (these The ring may be substituted, and examples of the substituent include the same alkyl group, norogen atom, nitro group, alkoxy group, and amino group as mentioned above.

)] General formula (■) [In the formula, X is an alkyl group (preferably a carbon number of 1 to 17
; for example, methyl, ethyl, propyl, butyl, octyl, tetradecyl, heptadecyl, etc.), aralkyl group (preferably, the alkyl residue has 1 to 4 carbon atoms; for example, benzyl, phenethyl, diphenylmethyl, etc.)
, aryl groups (e.g., phenyl, naphthyl, substituted phenyl, substituted naphthyl, etc.; substituents include alkyl groups such as methyl, ethyl, propyl, butyl; chlorine, bromine, iodine, fluorine, etc.; nitro groups; alkoxy groups such as methoxy, ethoxy, propoxy, butoxy; amino groups such as amino, methylamino, diethylamino; aralkyloxy groups such as benzyloxy) or acyl groups (for example, alkyl residues having 1 to 10 carbon atoms) (alkoxyacyl, aliphatic acyl, aromatic acyl, etc.); Y is O or NR2; R2 is an aralkyl group (for example, preferably, the alkyl residue has 1 to 4 carbon atoms;
(e.g., benzyl, phenethyl, diphenylmethyl, etc.) or aryl groups (e.g., phenyl, naphthyl, substituted phenyl, substituted naphthyl, etc.; substituents include alkyl groups such as methyl ethyl, propyl, butyl; chlorine,
Rogen atoms such as bromine, iodine, and fluorine: nitro group;
(alkoxy groups such as methoxy, ethoxy, propoxy, butoxy; amino groups such as amino, methylamino, diethylamino; aralkyloxy groups such as benzyloxy).

However, when Y is O, X is not an acyl group. ” - general formula () (in the formula, X, Y, Z and ring A are the same as above)
.

The novel spiropyran compound produced by the method of the present invention can be produced by appropriately selecting X, Y, Z, and ring A of the general formula Since it develops color upon action, it can be used for photosensitive, heat-sensitive, pressure-sensitive, or a combination of these recording materials and PH indicators.

It is particularly useful as a coloring agent for recording paper for pressure measurement (taking advantage of the fact that color density varies depending on the degree of pressure). All of the starting materials for the dipole cyclization reaction described above can be prepared according to conventionally well known methods.

That is, the compound of general formula (I) is, for example, Perkin (Pe
It can be produced from a coumarin derivative obtained by a reaction (in which acetic anhydride and sodium acetate are reacted on a salicylaldehyde derivative).

For example, the corresponding coumarin derivative may be reacted with phosphorus pentasulfide (when Z is s), or the ketal of the corresponding coumarin derivative may be reacted with R1-NH2 (when Z is NR'
in the case of). The compound of general formula () is, for example, the above-mentioned Hui
It can be produced by the method described in the review of sgen.
Currently, there is no known method for synthesizing the novel spiropyran derivative of the general formula () other than the method of the present invention. It is thought that it can be synthesized according to the method for synthesizing derivatives.

That is, the reaction formula is as follows. [In the formula, X,
．． Y, Z and ring A are the same as above, and w represents a halogen atom, an acid group such as ClO4 and BF4. ]
However, this method is difficult to synthesize the compound of general formula (V) and is economically disadvantageous compared to the method of the present invention.

According to one embodiment of the method of the invention, a spiropyran compound of the general formula () is prepared by using a compound of the general formula (I) and a precursor (precursor of nitrile oxide) generating the compound of the general formula (). Examples include hydroxamic acid chloride and acylated products of Aci-nitro compounds, and precursors of nitrile imine include hydrazide chloride, etc.)
and an organic solvent (preferably one without active hydrogen)
For example, it is dissolved in aromatic hydrocarbons such as benzene and toluene; ethers such as ether and tetrahydrofuran; and halogen-substituted aliphatic hydrocarbons such as ethylene chloride, and then converted into nitrile oxide from a nitrile oxide or nitrile imine precursor. Alternatively, an equimolar amount of a reagent for generating a nitrile imine, such as a base (e.g., an aliphatic amine such as triethylamine or an aromatic amine such as pyridine) is added dropwise at room temperature (e.g., added dropwise over 30 minutes to 1 hour), After that, for 1 to 5 hours, 20℃~
This can be achieved by maintaining the temperature below the boiling point of the solvent.

These reactions can be carried out at normal pressure. In the method of the present invention, when the above reagent also serves as a solvent, it is not necessarily necessary to use an organic solvent. Further, the compound of general formula () is preferably used in equimolar or excess amount relative to the compound of general formula (I). More specifically, the present invention will be explained in detail with reference to Examples, but the present invention is not limited to the following Examples.

Example 1 2-Phenylimino-2H-1-benzopyran 2.21V and benzphenyl hydrazide chloride 2.3
1 V of triethylamine is dissolved in 20 ml of dry benzene, and a solution of 1.0 IV triethylamine dissolved in 10 ml of benzene is added dropwise at room temperature.

After the dropwise addition, the precipitated colorless crystals of triethylamine hydrochloride were separated by P and the benzene was distilled off under reduced pressure to obtain crude 1', 3', 4'-triphenyl-spiro. [2H-l-benzopyran-2 ・5
'-(△2-1・2・4)triazoline]2.20y(
A yield of 53% was obtained. This crude product was recrystallized from cyclohexane to obtain white crystals with a melting point of 177-177.5°C. The elemental analysis values agreed with the theoretical values within the margin of error.
The following spiropyran derivatives were also synthesized using a similar method. [3'=acetyl=4'-butyl-6-chloro-1'-phenyl-spiro[2H-1-benzopyran-2 5'-(△2-1, 2, 4) triazoline], melting point 203-205°C1 '-P-chlorophenyl-7-diethylamino-3'-ethoxycarbonyl-4'-phenyluthbiro [2H-1-benzopyran-2, 5'-(△2-1, 2, 4) triazoline], melting point 218-221°C 3'-heptadecyl 1'-phenyl 4'-P-triluzepyro[3H-naphtho[2 ・lb]pyran 3 ・5
'-(△2-1 ・ 2 ・ 4) triazoline]
, melting point 233-236°C Example 2 2-phenylimino-2H-1-benzopyran 2.2
1y and 1.56v of benzhydroxamic acid chloride.
Dissolved in 1.0 g of dry benzene, 1.0 g of triethylamine
A solution of IV in 10 ml of dry benzene is added dropwise at room temperature.

After the dropwise addition, the mixture was stirred at room temperature for 1 hour, and then heated under reflux for an additional 10 minutes. After cooling, the precipitated triethylamine hydrochloride was separated, and the solvent was distilled off from the P solution under reduced pressure to give 3' and 4'
- Diphenyluspiro [2H-1-benzopyran-2
2.85 of a crude product (yield: 84%) of 5'-(Δ2-1.2.4)oxadiazoline] was obtained. The crude product was recrystallized from ethanol to obtain a pure product with a melting point of 156-156.5°C. The elemental analysis values agreed with the theoretical values within the margin of error. The following subiropyran derivatives were also synthesized using a similar method. 3'/4'-bis(P-chlorophenyl)
-7-Methoxyspiro [2H-1-benzopyran-2 ・5' (△2-1 ・2 ・4) oxadiazoline]
, melting point 189-192°C 7-(N-ethyl=N-phenyl)amino-3'-P-nitrophenyl-4'-phenyl-spiro[2H-1-benzobilane-2 ・
5'-(△2-1・2・4)oxadiazoline], melting point 227-231℃4'-benzyl-3'-(2・4
-dichloro)phenyl-6-methyl-spiro[2H
-1-benzopyran-2 ・5'-(△2-l・2・4
) Oxadiazoline], melting point 174-176℃ Example
3 Dissolve 1.62V of 2-thiocoumarin and 2.31V of benzophenyl hydrazide chloride in 20ml of dry benzene,
Triethylamine 1.0IV dried benzene 1 at room temperature
Drop the solution dissolved in 0.0 g.

After the dropwise addition, the precipitated triethylamine hydrochloride was stirred for 2 hours at room temperature, and the precipitated triethylamine hydrochloride was filtered out, and the benzene was distilled off under reduced pressure to give 2'4'-diphenyl-spiro[2H-1-benzopyran-2. A crude product of 3.05V (yield: 86%) of 5'-(Δ2-1.3.4)thiadiazolin was obtained. The crude product was recrystallized from a mixed solvent of n-hexane and cyclohexane to obtain colorless columnar crystals with a melting point of 134-135°C. The elemental analysis values agreed with the theoretical values within the margin of error. The following spiropyran derivatives were also synthesized using a similar method. [2'-Benzoyl-7-diethylamino-4'-O-tolyluzepyro [2H-1-benzopyran-2,5'-(△2-1,3,4)thiadiazolin]
, melting point 205-208℃ 7-benzyloxy-2'-
Tert-butyl-4'-phenyl-spiro[2H-
l-benzopyran-2 ・5'-1 (△2-1, 3, 4
) thiadiazoline], melting point 187-190°C 2'-acetyl-4'-p-nitrophenyl-spiro[3H-naphtho[2,1-b]pyran-3,5'-(△2-1,
3.4) Thiadiazolin], melting point 264-268°C Example 4 1.62y of 2-thiocoumarin and 1.56y of benzhydroxamic acid chloride were dissolved in 20ml of dry ether, and 1.01y of triethylamine was dissolved in 10ml of 10mi of dry ether. The dissolved solution is added dropwise at room temperature.

Claims (1)

[Claims] 1. A compound of general formula (III) characterized by subjecting a compound of general formula (I) and a compound of general formula (II) to a dipolar cyclization reaction.
) method for producing spiropyran compounds. ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (I) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (III) [In the formula, Z is S or NR^1 ,R
^1 is an alkyl group, an aralkyl group or an aryl group;
Ring A is a benzene ring or a naphthalene ring; Y is O or NR^2; R^2 is an aralkyl group or an aryl group; X is an alkyl group, an aralkyl group, or an aryl group when Y is O; is NR^2, an alkyl group,
Represents an aralkyl group, an aryl group or an acyl group. ]