RU2839770C1 - Growth-stimulating agent for pre-sowing treatment of seeds - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to organic chemistry, specifically to a process for the preparation of N-phthaliliden-bis-[4-(7-cyclohepta-1,3,5-trienylphenylimine)] of formula I, which has growth-stimulating activity on agricultural plants and can be used as a growth promoter for improving the quality of seed material. Method involves single-step reaction of aniline, terephthalic aldehyde and tropylium tetrafluoroborate at room temperature. Synthesis time is 2 hours, the solvent used is ethanol and the end product is separated.

EFFECT: disclosed method is a single-step and safe method.

1 cl, 3 tbl, 2 ex

Description

The invention relates to the field of organic chemistry, namely to a method for producing N-phthalylidene-bis-[4-(7-cyclohepta-1,3,5-trienylphenylimine)], which can be used in agriculture as a growth stimulator in agricultural plants to improve the quality of seed material.

A method for producing (1E,1 ¹ E)-1,1 ¹ -(1,4-phenylene)bis[N-4-(E)-phenyldiazenylphenylmethanimine] is known, which consists in the interaction of 4-aminoazobenzene with dialdehyde in the presence of glacial acetic acid in a dry methanol medium at boiling for 1 hour. The reaction mass is cooled and kept for 10-15 hours at 0-5 ° C (Dikusar, E.A. Synthesis of (E,E)-azoazomethines based on 4-aminoazobenzene / E.A. Dikusar, L.N. Filippovich, S.N. Shahab, S.K. Petkevich, S.G. Stepin // Bulletin of the National Academy of Sciences of Belarus. Series of Chemical Sciences. - 2018. - Vol. 54. - No. 1. - Pp. 58 - 71).

The disadvantage of this method is the use of a more toxic solvent, methanol, and the holding of the reaction mass for maturation of the target product for 10-15 hours at 0-5°C. In addition, the compound does not have growth-stimulating activity on agricultural plants.

The closest analogue is the method for obtaining N-phthalylidene-bis-[4-(7-cyclohepta-1,3,5-trienylphenylimine)], which is carried out in two stages. In the first stage, 4-(7-cyclohepta-1,3,5-trienyl)aniline is obtained by reacting tropylium tetrafluoroborate with aniline. In the second stage, the reaction of the resulting 4-(7-cyclohepta-1,3,5-trienyl)aniline with phthalaldehyde in a benzene medium is carried out (Esenbaeva, V.V. Synthesis and mesomorphism of N-phenylmethylene-4-(7-cyclohepta-1,3,5-trienyl)anilines / V.V. Esenbaeva, A.I. Smirnova, N.V. Usoltseva [et al.] // Liquid crystals and their practical use. - 2015. - Vol. 15. - No. 2. - Pp. 26-34).

The disadvantage of this method is the multi-stage process and the use of benzene as a solvent, which belongs to hazard class II (highly hazardous substance).

The technical result of the invention is achieved in the development of a single-stage, safe method for obtaining N-phthalylidene-bis-[4-(7-cyclohepta-1,3,5-trienylphenylimine)] of formula I, which has growth-stimulating activity for agricultural plants.

The essence of the invention is that compound I is obtained by the interaction of aniline (1), terephthalaldehyde (2) and tropylium tetrafluoroborate (3) in an ethanol medium with the reaction mass maintained at room temperature for 2 hours, followed by isolation of the target product by known methods. The reaction proceeds according to scheme 1:

Scheme 1

An advantage of the claimed compound of formula I is its growth-stimulating activity in relation to agricultural plants.

The invention is illustrated by the following examples.

Example 1. N-phthalylidene-bis-[4-(7-cyclohepta-1,3,5-trienylphenylimine)] ( a compound of formula I). A mixture of 0.56 g (6 mmol) of aniline, 0.39 g (3 mmol) of terephthalaldehyde, 1.07 g (6 mmol) of tropylium tetrafluoroborate in 9 ml of ethanol was kept at room temperature for 2 hours. The separated crystals were filtered off, washed with ethanol, and dried. The yield of the product was 1.02 g (72.3%).

Example 2. The growth-stimulating activity of the compound of formula I was tested in laboratory conditions on higher plants. Spring wheat ( Triticum aestivum L.) of the Kamenka variety was selected as the test crop. In the experiment, wheat seeds were germinated in Petri dishes on filter paper. Before sowing, the seeds were soaked for 1 hour in the test substance according to the experimental scheme (Table 1). Solutions were prepared by diluting the mother liquor with a concentration of 1×10 ^-1 %. 10 seeds were sown in a Petri dish. The plants were germinated for a week at a temperature of 20±2°C. The average values of germination energy, germination (Table 1), sprout and main embryonic root length, sprout and root weight of the test object (Tables 2, 3) were calculated.

Table 1

The effect of the claimed compound of formula I on the germination and germination energy of spring wheat seeds, %

Options Percentage of germinated seeds Germination energy Germination ± Cv ± Cv ± Cv Control (water) 85±2 6 83±3 7 80±4 10 1×10 ^-2 % 80±0 0 90±0 0 90±0 0 1×10 ^-3 % 100±0 0 100±0 0 100±0 0 1×10 ^-4 % 95±5 11 100±0 0 100±0 0

In the variant with the substance concentration of 1×10 ^-3 % in the solution, the wheat seeds germinated 100 % already on the second day of the experiment. Dilution of this solution by 10 times resulted in an increase in the number of germinated seeds, germination energy and germination, maximum values of the characteristics were noted. The difference with the control variant was 15 %, 17 % and 20 %, respectively, and is mathematically provable. The values of the studied characteristics varied insignificantly ( Cv less than 10 %).

Table 2

Increase in biometric indicators of spring wheat

Options Root length Sprout length increase to control, % reliability increase to control, % reliability 1×10 ^-2 % -8.6 Reliable -15.5 Reliable 1×10 ^-3 % 113.6 Reliable 101.2 Unreliable 1×10 ^-4 % 103.7 Reliable 119.0 Reliable

The processing of the obtained data showed that the changes in the sprout length in the variant with the concentration of the claimed compound of formula I of 1×10 ^-3 % are unreliable. In this variant, the maximum increase in the length of the main embryonic rootlet to the control was noted, it was 11 mm. With further dilution of the solution, a decrease in the increase in the rootlet length was observed, the average elongation was 3 mm. The sprout length increased by 16 mm and was the maximum in the experiment. The dispersion analysis showed the reliability of the difference in the obtained experimental data.

In variants with concentrations of 1×10 ^-3 % and 1×10 ^-4 %, an increase in the biomass of wheat sprouts was noted; the increase relative to the control was 550-800 mg.

Table 3

Increase in biomass of spring wheat seedlings

Options Root Sprout increase to control, % reliability increase to control, % reliability 1×10 ^-2 % 110.9 Unreliable -80.8 Reliable 1×10 ^-3 % 157.4 Reliable 114.6 Reliable 1×10 ^-4 % 134.7 Reliable 113.9 Reliable

The maximum increase was noted in the variant with the concentration of the claimed compound of formula I of 1×10 ^-3 %, in this variant the greatest variation of the feature was observed. Further dilution of the test substance, although it leads to an increase in biomass relative to the control, but the increase was somewhat lower. The dispersion analysis showed the reliability of the difference in changes in the mass of embryonic roots and wheat sprouts under the influence of the claimed compound of formula I.

The study showed that N-phthalylidene-bis-[4-(7-cyclohepta-1,3,5-trienylphenylimine)] at a concentration of 1×10 ^-2 % has an inhibitory effect on sprouts of spring wheat of the Kamenka variety. The maximum stimulating effect of the test substance was noted in the variant with a concentration of 1×10 ^-3 %, which indicates the possibility of using N-phthalylidene-bis-[4-(7-cyclohepta-1,3,5-trienylphenylimine)] for treating spring wheat seeds for the purpose of their disinfection and stimulation of growth processes.

Claims (3)

Method for preparing N-phthalylidene-bis-[4-(7-cyclohepta-1,3,5-trienylphenylimine)] of formula I , which includes a single-stage reaction of aniline, terephthalaldehyde and tropylium tetrafluoroborate at room temperature, characterized in that the synthesis time is 2 hours, ethanol is used as a solvent and the target product is isolated.