JPS6075459A - N-substituted benzylmaleimide derivative - Google Patents

Abstract

NEW MATERIAL:An N-substituted benzylmaleimide derivative shown by the formula I (R1 and R2 are H, or lower alkyl; R3 and R4 are H, halogen, lower alkyl, or lower alkoxy with the proviso that R1 and R2 are not H at the same time). EXAMPLE:N-2-Chloro-alpha,alpha-dimethylbenzylmaleimide. USE:Having repelling action on harmful organisms in water, being processed into a form such as coating compound, solution, emulsion, etc., useful as antifouling coating compounds, antifouling agent for fishing nets, etc. PREPARATION:Maleic anhydride shown by the formula II is reacted with a substituted benzylamine shown by the formula III at 20-100 deg.C for 0.5-2hr. The prepared N-substituted benzylamaleinimic acid shown by the formula IV is not isolated, and subjected to ring closure through dehydration in the presence of an acid catalyst or it and a small amount of an aprotic polar solvent at 80- 200 deg.C, to give a compound shown by the formula I .

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to novel N-substituted pendylmaleimide derivatives having a repellent action against harmful aquatic organisms.

1- Up to now, compounds having a repellent effect on harmful aquatic organisms have the general formula (wherein, X represents a halogen atom, Y represents a lower alkyl group or a halogen atom, and 2 represents a lower alkyl group or a nitro group). The N-substituted maleimides shown are known.

(For example, see Special Publication No. 57-43108))' I
! However, the effect is not completely satisfactory.

The present inventors conducted extensive research in order to develop a compound that has an even better repellent effect on harmful aquatic organisms, and as a result 1. The N-substituted pendylmaleimide derivative of the present invention has an excellent repellent effect on harmful aquatic organisms. It was discovered that the compound is a new compound, and the present invention was completed based on this finding.

That is, the present invention is based on the general formula (wherein R1 and Tori represent a hydrogen atom or a lower alkyl group, and RI and Tori represent a tree, a halogen atom, a lower alkyl group, or a lower alkoxy group. However,
(except when R1 and R1 are both hydrogen atoms) is an N-substituted pendylmaleimide derivative represented by the following.

All of the compounds of the present invention are new compounds that have not been published in any literature, and representative examples thereof are shown in Table 1-1. Note that the compound numbers are referred to in the Examples below.

Table 1 6- The novel N-substituted pendyl maleimito'p,7. (r[J
and the substituted benzylamine (m) at a temperature range of 20 to 100°C for 5 to 2 hours, and then the produced 4-tN-ft-substituted benzylmaleimide acid compound (m) was isolated (this was treated with an acid catalyst). Alternatively, add an acid catalyst and a small amount of aprotic polar solvent and heat at 80 to 200°C in the presence of these.
It can be produced in high yield by carrying out a dehydration ring-closing reaction at a temperature range of 1 to 10 hours.

(In the formula, R1+ horse, R, and horse have the same meanings as above) =5- Examples of the solvent used in the reaction include solvents that are inert to one reaction, and specifically, for example, octane, decane, etc. , ligroin, aliphatic hydrocarbons such as cyclohexane, henzene, toluene, xylene.

Aromatic hydrocarbons such as ethylbenzene, diisopropylbenzene, solvent naphtha, halogenated aromatic hydrocarbons such as chlorobenzene, dichlorobenzene, chlorotoluene, chloroisoglobylbenzene, n-butyl ether, diisoamyl ether, dioxane, etc. , nitriles such as acetonitrile, propionitrile, and benzonitrile, and ketones such as methyl ethyl ketone and methyl isobutyl ketone.

The acid catalyst used in the dehydration reaction includes those commonly used as dehydrating agents. Specifically, for example, hydrochloric acid and sulfuric acid.

Sulfuric anhydride, trifluoroacetic acid, trifluoromethanesulfonic acid, phosphoric acid, acetic anhydride, thionyl chloride.

Examples include phosphorus oxychloride and toluenesulfonic acid. Specific examples of the aprotic polar solvent used in the dehydration ring closure reaction include dimethylformamide, dimethyl sulfoxide, hexamethylphosphoramide, and tetramethylurea.

The novel N-substituted pendylmaleimide derivative represented by the general formula (g) has a repellent effect on harmful aquatic organisms, and can be used as an active ingredient in the form of paints, solutions, emulsions, etc. to produce antifouling paints and fishing nets. Can be used as an antifouling agent, etc.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 2 n Oml of toluene was charged into a 500 m/4-meter flask equipped with a thermometer, a cooling tube equipped with a water separator, a dropping funnel, and a stirrer, and 195 ml of maleic anhydride was added to the flask.
f (0.2 mol) was added and dissolved.

Then, concentrated sulfuric acid (1.0 PF, 0.0097 mol) and 6 ml of dimethyl7-ylformamide were added, and the mixture was allowed to react for 4 hours while azeotropically removing water produced by the reaction under stirring and heating under reflux.

After completion of the reaction 1. After distilling off xylene from the reaction solution.

N-2-chloro-α, α-
Dimethylbenzylmaleimide (colorless liquid.

n2゜o, t566B, b, pl 45-150℃
/ 0.1 mxHf) to 4692 (yield 8BC
I)) obtained.

Example 2 50 g of xylene was charged into a 500 ml four-bottle flask equipped with a thermometer, a cooling tube with a water separator, a lower funnel, and a stirrer, and 19.5 g of maleic anhydride was added thereto.
(0.2 mol) was added and dissolved. Then, to this, 100 d of xylene and 52.
A solution in which 69 ((1.2 mol)) was dissolved was added dropwise at room temperature with stirring.

Then concentrated sulfuric acid 1. Of (0,0097 mol) was added, and the reaction was allowed to proceed for 4 hours while stirring, heating, and refluxing the reaction to azeotropically remove the water produced.

8- After completion of the reaction 1. After distilling off xylene from the reaction solution.

N-(α,α-dimethylbenzyl)maleimide (colorless liquid, n”u’ 1.55
00.

b, pl 35-136℃ 101 Dragon Hf), 56.
5? (yield: 75.0%).

Example 3 A reaction was carried out in the same manner as in Example 1, except that 4-chloro-α,α-dimethylbenzylamine was used in place of α,α-diethyl-benzylamine in Example 1, and N
-4-chloro-α,α-dimethylbenzylmaleimide (
Colorless needle crystals, m, p78-80℃) at 25.4F
(yield 550%).

Example 4 The following tests were conducted on the compounds of the present invention (11 to (7)) shown in Table-1.

Dispense 10 Artemia that hatched within 48 hours into a measuring cylinder, and add 1 artificial seawater to make 19 ml. Transfer this to a glass Petri dish and leave it for 24 hours (.

9- 1 to the present invention compound 2 in advance, cyclohexanone 90m%,
The emulsion prepared with TVθen-808wt% was diluted to a predetermined concentration with artificial seawater, 1 ml of this was added to a Petri dish, and the concentration in the seawater in which Artemia was swimming was adjusted to 10 p.
Let it be pm.

Cover the petri dish and leave it in a constant temperature room at 20°C.

After 24 hours, the number of dead Artemia was counted, and the mortality rate was calculated from kneading.

Mortality rate - x 1o O (qb) A: Survival rate in untreated area Survival rate in Bi treated area In addition, the test was repeated three times in each area ◎ In addition to the 9 compounds of the present invention, the following 3 compounds were used. A similar test was conducted using as a comparative compound.

Comparative compound (lliN-2-chlorophenylmaleimide (compound described in Japanese Patent Publication No. 57-43108) 10- Comparative compound (2); N-benzylmaleimide 0 (0, A, Eto, 73183X described compound) Comparative compound?I (31+ N-2-chlorobenzylmaleimide The results are shown in Table 2.

Example 5 The same tests as in Example 4 were conducted on the compounds (8) to o9 of the present invention shown in Table-1.

The results are shown in Table 3.

15-

Claims (1)

[Claims] In the general formula C, R1 and R represent a hydrogen atom or a lower alkyl group, and R1 and R4 represent a hydrogen atom, a halogen atom, a lower alkyl group, or a lower alkoxy group. However, the N-substituted pendylmaleimide derivative represented by () is excluded, except when R3 and R3 are both hydrogen atoms.