SU1698248A1 - Method of preparing 9-h-9-chloro-1,10-anthracenedionon - Google Patents

Abstract

The invention relates to anthraquinones, in particular to the preparation of 9-n-9-chloro-1,10-anthracenedione, which is used in the synthesis of dyes and biologically active compounds. The goal is to increase the yield of the target product and simplify the process. It is carried out by the reaction of 1-hydroxy-9,10-anthraquinone with phosphorus pentachloride in the presence of triethylamine in boiling benzene or toluene at a molar ratio of reagents of 1: 1: 2. These conditions can reduce the number of stages to one and increase the product yield to 94-97%.

Description

The invention relates to anthraquinones, in particular, to a method for producing 9-H-9-chloro-1,10-anthracenedione, which is one of the simplest representatives of anachinones - highly reactive substances - and can be used as an intermediate for the synthesis of dyes , biologically active compounds, additives that improve the physicochemical properties of polymers.

The purpose of the invention is to increase the product yield and simplify the process.

Example 1.11.1 g (0.05 mol) of 1-hydroxy-9,10-anthraquinone, 10.4 g (0.05 mol) of phosphorus pentachloride and 10.1 g (0.1 mol) of triethylamine are heated with stirring boil in 250 ml of benzene for 1.5 hours. Completion of the reaction is judged by the amount of precipitated triethylamine chlorohydrate. 6.8 g (0.05 mol) of triethylamine hydrochloride are filtered off, the filtrate is evaporated in a vacuum, the residue is washed with heptane and recrystallized from benzene-heptane (1: 1). 11.4 g of the expected product are obtained. Yield 95%. M.p. 133 ° C (literature data: 133 ° C).

Example 2. 5.55 g (0.025 mol) of 1-hydroxy-9,10-anthraquinone, 5.2 g (0.025 mol) of phosphorus pentachloride and 5.05 g (0.05 mol) of triethylamine are heated with stirring until boiling in 150 ml of benzene for 1 hour. The reaction mixture is treated as in Example 1. 3.4 g of triethylamine hydrochloride are obtained; 5.8 g of the desired product with a yield of 97%. M.p. 133 ° C.

Example 11.1 g (0.05 mol) of 1-hydroxy- 9,10-anthraquinone, 10.4 g (0.05 mol) of phosphorus pentachloride and 15.15 (0.15 mol) of triethylamine are heated with stirring to a boiling point of 250 ml of benzene for 1.5 hours. The reaction mixture is treated as in Example 1. 6.8 g of triethylamine hydrochloride are obtained; 11.3 g of the desired product with a yield of 94%. M.p. 133 ° C.

Example 4 (comparative). 11.1 g (0.05 mol) of 1-hydroxy-9,10-anthraquinone. 10.4 g

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(0.05 mol) phosphorus pentachlorides and 8.1 g (0.08 mol) of triethylamine are heated under stirring to boil in 250 ml of benzene for 1.5 hours. The reaction mixture is worked up as in Example 1. 3.4 g are obtained. triethylamine hydrochloride; 5.3 g of the desired product with a yield of 44%. M.p. 133 ° C.

When used in the proposed method, other tertiary amines (tripropyl amine, tributylamine, triisopropylamine, and pyridine), dialkyl esters (diethyl, dipropyl, dibutyl), sulfides (dioctyl, dipentyl), ketones (acetone), methyl ethyl methyl. phosphatobenzantron with a yield of 41-75%.

In the case of primary and secondary amines and amides, they interact with phosphorus pentachloride and form the known products of general formula R2NPCI4,.

. With alcohols and alcohols, phosphorus pentachloride reacts to give ROPC14 phosphorans. An attempt to use other bases as an additive to the reaction mixture of phosphorus pentachloride with 1-hydroxy-9,10-anthraquinone does not give a positive result. In the absence of additives, the product of the reaction is phosphabenzentron.

Example 5 (comparative). 11.1 g (0.05 mol) of 1-hydroxy-1,10-anthraquinone, 10.4 g (0.05 mol) of phosphorus pentachloride in the presence of a base are heated with stirring until boiling in 250 ml of benzene for 1.5 hours The progress of the reaction is judged by the amount of base hydrochloride liberated or at the end of the evolution of hydrogen chloride from the reaction mixture. It is filtered, if there is a precipitate, the filtrate is evaporated in vacuo, the residue is washed with heptane and recrystallized from benzene-heptane (1: 1). Phosphabenzantron is obtained in 93% yield. M.p. 150 ° C.

The spectral data coincide with the known. The unequal ratio of the original anthraquinone and phosphorus pentachloride leads to a decrease in yield and contamination.

product reagents. A two-fold amount of triethylamine is necessary to bind the liberated hydrogen chloride and to catalytically convert the starting 1-hydroxy-9,10-anthraquinone VE-hydroxy-1,10 antraquinone, and then in the condensation reaction with phosphorus pentachloride. When using less than twice the amount of triethylamine, the yield of the target product decreases. With a more than twofold excess of triethylamine, neither the degree of purity nor the yield of the product is changed, so it is impractical.

When the temperature of the reaction mixture is below 80 ° C, the process does not proceed. Boost

temperatures above 100 ° C lead to contamination of the target product and a decrease in its yield. In this case, an inert solvent that dissolves the reagents should be used as the reaction medium. The conditions listed are met by toluene and, preferably, benzene.

Thus, the use of the proposed method allows to simplify the process by reducing the number of stages

from two (according to the prototype) to one, and also to increase the product yield from 85% (according to the prototype) to 94-97%.

Formula of the invention. A method for producing 9-H-9-chloro-1,10-anthracecenone by reacting 1-hydroxy-9,10-anthraquinone with phosphorus pentachloride at an equimolar ratio of reagents in boiling benzene, characterized in that in order to simplify the process and

the product yield is increased, the interaction is carried out in the presence of triethylamine at a molar ratio of 1-hydroxy-9,10-anthraquinone: triethylamine 1: 2-3.

Claims (1)

Claim The method of producing 9-H-9-chloro-1,10-anthracene by reacting 1-hydroxy-9,10 antraquinone with phosphorus pentachloride at an equimolar ratio of reagents in boiling benzene, characterized in that, in order to simplify the process and increase the yield of the product, the interaction is carried out in the presence of triethylamine at a molar ratio of 1-hydroxy-9,10-anthraquinone: triethylamine = 1: 2-3.