SU1131866A1 - Process for preparing 3,5-diarylphenols - Google Patents

Abstract

METHOD OF OBTAINING 3,5-DIARYLPHENOLS of general formula, AG1 AG2 where Arg is phenyl, n-nitrophenylidene, 2-thienyl ,,, 2-selenyl, Arj-phenyl, 2-furyl, 2-thiensh1, N-nitrophenylidene, using corresponding to the chalcone of the general formula AG1-CH CH-C-AG2 O, where Arj and Ar have the indicated values, and the condensation process, which is current, in order to simplify the process, increase the yield of the target product, as well as expand the range of products obtained. products, the corresponding chalcone is subjected to interaction with bromide

Description

SAE EO

a a The invention relates to an improved process for the preparation of 3,5-diaripphenols, which can be used as starting materials for the production of polymers used in the manufacture of molded products and as pesticides. These phenols can also serve as valuable intermediates for organic synthesis. The closest to the proposed method is the preparation of 3,5-diarylphenols, in which chalcones are condensed with acetone dicarboxylic acid diethyl ether and the cyclohexene is brominated while illuminating the UV in ethyl acetate and acetamide in the presence of N-bromosuccinimide as a catalyst. The bromination product spontaneously undergoes aromatization to form 2-OXY-4,6-diphenylisophthalic acid diethyl ester, which is added as potassium salt to increase the purity of the product (when the compound is treated with an alkali solution). The latter is hydrolyzed to 2-hydroxy-4,6-diphenylisophthalic acid, decarboxylation / of which at 205-230 ° C and reduced pressure leads to the formation of 3,5-diarylphenode lj. The disadvantages of this method are the multistage - five hundred; total yield of the final product (26%); as well as a narrow set of iPi-CH CH-C-Af2- - Ph3P -CHjCOOl JHu CHjCOOH BOILING

where Ph is phenyl}

Ph - pyridinyl%

In order to ensure a strict reaction orientation, the specified process conditions should be maintained. 50

Example 1.A. Preparation of O-2-triphenylphosphonio-3, 5-diphenylbenzene 1-oxide.

A mixture of 1.04 g (0.005 mol) of 1-phenyl-2-benzoylethylene and 2.38 g (0.005 mol) of 55 bromide 0 -triphenylfbsphorinyl or adenoacetonylpyridinium, 5 g of ammonium acetate, 6 ml of glacial acetic acid;

boil for 1 hour. After cooling, the reaction mixture is poured into 100 ml of ice water. The precipitation is filtered off, washed with water and recrystallized from a mixture of pyridine - water 1: 1. 1.9 g (75%) of chromatographically pure (, 45, Silufol UV 254, chloroform-alcohol eluent, 5%) 1-oxide-2-triphenylphosphonio-3, 5-diphenyl benzene is obtained.

For elemental analysis and determination of constants, the substance of the substituents in the formation of xp phenols (only phenyl). The aim of the invention is to simplify the process, increase the yield of target products and expand the yield of target products and expand the range of products obtained. This goal is achieved by the proposed method for the preparation of 3,5-diaryl4) enols of the general formula i-7- (OVoH, where Arj is phenyl, -nitrophenylidene, 2-thienyl, 2-elelenyl; Ar ,, -phenyl, I-nitrophenylidene, 2- furyl, 2-thienyl, by condensation of the corresponding chalcone of the general formula GgCH CH-C-AG2 O de Ag. and Ag have the indicated values, in the presence of ammonium acetate in acetic acid with a romide-salt romide (O-triphenylphosphorenylidene acetonylpyridinium with boiling alkaline by hydrolysis of the 1-OXIDO-2-triphesh1fsophio-3, 5-diarylbenzene obtained in this way o-ethanol solution at the boiling point of the mixture The reaction proceeds according to the following scheme: CH-C-CH2Py Br kon Art ETHANOL / H2O j, but recrystallized from ethanol: mp: 28.04; H 5 , 28. Cl, H Calculated,%: C 85.35, H 5.33. B. Preparation of 3,5-diphenylphenol (q Mixture 2.53 g 0.005 mol) 1-oxide-2-triphenylphosphonio-3, 5- diphenylbenzene and 0.6 g (0.015 mol) of sodium hydroxide are boiled in 10 ml of an aqueous solution of ethanol (1: 1) for 15 hours until the precipitate has completely dissolved. The reaction mixture is evaporated to half the volume. The remaining alkaline solution is acidified with 2N hydrochloric acid until slightly acidic (pH 6-7) and extracted three times with chloroform. The extract is dried over sodium sulfate. The solvent is evaporated. The remaining yellow oil is chromatographed on a column (30-1 cm) with silica gel L-100/160 {I, eluent - chloroform, 4. I get 0.98 g (80%) of chromatographically pure 3,5-diphenylphenol. For elemental analysis and determination of constants, the substance is additionally purified by recrystallization by petrolization by petroleum ether. M.p. 94-95 C Found,%: C 88.16, - H 5.63. . Is calculated,%: C 87.73, H 5.69. Example 2: A. Preparation of 1-oxide-2-triphenylphosphonio-3-p-nitrophensh1-5-phenylbenzene. 1.26 g (0.005 mol) of 1-phench I-2-h-nitrobenzoylethylene is condensed with 2.38 g (0.005 mol) of bromide with -three: phenylphosphoranylidenedenacetonylpyridinium in the presence of 5 g of ammonium acetate and 6 ml of acetic acid as in example lA.sa with the exception that, as a result of the poor solubility of the chalcone used in the reaction medium, the reaction is carried out under heterophasic conditions and the recycle time is increased from 1 hour to 3 hours. The product is recrystallized from pyridine-water 1 :one. 1.69 g (75%) of chromatographically pure 1-oxide-2-triphenylpho-fonio-3-p-nitrophenyl-5-feshbenzene are obtained. M.p. 223-5 ° C. Found,%: C 77.97J, H 4.35. G jHjgNO.,. Vmsleno,%: C 78.43, H 4.71. B. Preparation of 3n-nitrophenyl-5-phenylphenol (8). The process is conducted as in example 1B with. using 2.25 g (0.005 mol) of 1-oxide-2-triphenylphosphonio-3-p-nitrophenyl-5-phenylbenzene and 0.6 g of sodium hydroxide, but during chromatography of the reaction product, its R decreases to 0.3 ( , eluent chloroform), and ethanol is used instead of petroleum ether to recrystallize the resulting phenol. 1.12 g (77%) of 3-p-nitrophenyl-5-phenylphenol is obtained. M.p. 190-2s. Found,%: C 72.01, H 4.58. C, gH, N03. Calculated,%: C 72.35, H:, 46. The conditions described for Example 2A and 2B also concern a process for the preparation of 3-thienyl-5-p-nitrophenylphenol (,). Example 3. A. Preparation of 1-oxide-2-triphenylphosphonio-3 (thienyl-2) -5 (pyryl-2) benzole. 1.02 g (0.005 mol) of 1- (furyl-2) -2 (theonyl-2) ethylene is condensed in the presence of 5 g of ammonium acetate and 6 ml of glacial acetic acid with 2.38 g (0.005 mol) of bromide ( 0-triphenylphosphoranylideneacetonylpyridinium. The process is carried out as in Example 1A, with the exception that due to the lower stability of chalcones containing heterocyclic substituents, the reaction time is reduced to 40 minutes. 1.53 g (61%) of 1-oxide-2-triphenylphosphonium- is obtained. 3 (thienyl-2) -5 (furyl-2) -benzene. Mp 281-C C. Found,%: C 75.43, H 4.92. Calculated,%: C 75.93 { H 5.14. B. Preparation of 3- (tyenyl-2) -5 (furyl -2) phenol (g) is also carried out as in imer 1B using 2.51 (0.005 mol) 1-oxide-2 (triphenylphosphonio) -3 (thienyl-2) -5 (furyl-2) benzene and 0.6 g (0.015 mol) of sodium hydroxide Obtain 1.05 g ( 87%) 3- (tinyl-2) -5 (furyl-2) phenol (g), mp: 116-7 ° C. Found,%: C 69.11; H, 3.84. Calculated,% : C, 69.47; H, 4.14. Changes in the reaction time, shown in Example 3, also concern the method of obtaining 3 (seleniens 1-2) -5 (thienyl-2) phenol. . . . The resulting new β-d 3,5-diarylphenols are stable colorless or slightly yellow substances, crystalline, well soluble in acetone.

51131866

chloroform, benzene, ethanol (except for phenols (& b), worse in ether and bad in saturated hydrocarbons.

The properties of the resulting 3,5-diarylpha-5 NOLOV are given in the table.

Thus, the invention in comparison with the known method allows to simplify the process of obtaining the

left products, reducing the number of stages from five to two; to increase the total yield of the target products from 26% to 34-60% i to obtain a series of 3,5-diarylphenols not previously described, which contain heterocyclic substituents and can be used to synthesize new polymeric materials, as well as have pesticidal activity.

Claims (2)

METHOD FOR PRODUCING 3,5-DIARIL- Phenols of the general formula, where Ar ^ is phenyl, n-nitrophenylidene, 2-thienyl,., 2-selenyl, Ag ₂ -phenyl, 2-furyl, 2-thienyl, H-nitrophenylidene using the corresponding chalcone of the general formula AG1-CH = CH-C-AG ₂ II 'about where Ar | and Ar ₂ have the indicated meanings and of the condensation process, characterized in that, in order to simplify the process, increase the yield of the target product, as well as expand the range of products obtained, the corresponding chalcone is reacted with O-triphenylphosphoranylideneacetonylpyridinium bromide in the presence of ammonium acetate in acetic acid medium by boiling the reaction mixture followed by alkaline hydrolysis of the resulting 1-oxide-2-triphenylphosphonio-3,5-diarylbenzene by boiling in an aqueous ethanol solution. SU „„ 1131866