SU440365A1 - The method of obtaining 9,9-bis- (4-carboxyphenyl) -fluorene or its derivatives - Google Patents

Description

one

The invention relates to a process for the preparation of aromatic dicarboxylic acids or their derivatives, which can be used as starting monomers for the synthesis of heat and heat resistant polymers.

In the proposed method for the preparation of 9,9 bis- (4-carboxyphenyl) -fluorene or its derivatives, fluorenone is condensed with toluene in the presence of polyphosphoric acid with

the subsequent oxidation of the resulting 9,9-ditolylfluorene to either the isolation of the target product, or the conversion of the resulting dicarboxylic acid to the corresponding acid chloride or ester, or dihydrazide by known methods.

Synthesis of 9,9-b, is (4-carboxyphenyl) -fluorene or its derivatives is carried out according to the following scheme;

Condensation of fluorenone with toluene in polyphosphoric acid, resulting in the formation of 9,9-ditolylfluorene (I), is a new way to produce a previously undescribed 9,9-derivative fluorene. The use of polyphosphoric acid as a reaction medium makes it possible to obtain 9,9-ditol, ilofluorene from the available starting materials in a single-stage process under relatively mild temperature conditions (at toluene boiling).

The oxidation of 9,9-ditolylfluorene (I) is carried out analogously to one of the known methods for the oxidation of benzene homologues to aromatic carboxylic acids with a solution of potassium dichromate at a temperature of 270-280 ° C. 9,9-bis- (4-carboxyphenyl) -fluorene (I) is obtained with a good yield.

The synthesis of derivatives of 9,9-b, is- (4-carboxyphenyl) -fluorene is carried out analogously to the synthesis of the corresponding derivatives of the known aromatic dicarboxylic acids. Chloride 9,9-bis- (4-carboxyphenyl) -fluorene (III) is obtained by the interaction of 9,9-bis- (4-carboxyphenyl) -fluorene (P) with an inorganic acid chloride — thionyl chloride at boiling of thionyl chloride. 9,9-bis- (4-carboxyphenyl) -fluorene (IV) dimethyl ester is obtained by esterification by 9.9-bis (4-carboxyphenyl) -fluorene (II) methanol in the presence of conc. sulfuric acid boiling methanol. The dihydrazide 9,9-bis- (9-carboxylphenyl) -fluorene (V) is synthesized from 9,9-bis- (4carboxyphenyl) -fluorene (IV) dimethyl ether and hydrazine hydrate in methanol at the boiling point of the reaction mass.

Each of the I – V products synthesized according to the above scheme can be used independently as a new initial monomer for the synthesis of new heat and heat resistant polymers.

Example.

1. Synthesis of 9,9-ditolylfluorene.

36.0 g (0.2 mol) of fluorech, 64.0 ml (0.6 mol) of dry toluene and 700 g of polyphosphorous are charged into a 2 l flask equipped with a broom, a hydraulic shutter and a reverse water cooler with a calcium chloride tube. acid.

The contents of the flask are heated at 140 ° (in a bath) for 5 hours, cooled to 80 ° and poured into 4 liters of ice water. Phosphoric acid is neutralized by the addition of sodium bicarbonate. The precipitated product is filtered off, washed on the filter with water, 700 ml of ethanol and dried in air at 60 °. The product is further extracted with 300 ml of glacial acetic acid and dried at 80 °. The yield after extraction is 19.6 g. The product obtained and recrystallized from ethanol has an mp. 164-165 ° C; the elementary composition of CgtNsg, calculated: C 93.60%; H 6.40%; found: C 93.56%, H 6.29%.

2. Synthesis of 9,9-bis- (4-carboxyphenyl) -fluorene.

In a swinging autoclave, a 0.5 liter was charged with 12 g of 9.9-bis (4-tolyl) fluorene, 21 g of K2Cr2O7,

2 ml of H2SO4 (94%) and 180 ml of water. The oxidation is carried out at 270-280 ° for 5 hours. The reaction mass is discharged, the aqueous solution of the potassium salt of the acid is filtered off from Cr203 and acidified with an aqueous solution of hydrochloric acid. The precipitate formed is filtered and washed with water until neutral. The resulting acid is at 120 °. Yield 9.8 g. The product recrystallized from ethanol has an mp. 345-

347 ° C; acid number 196 mg of NaOH / 1 g to-you (theoretically. 197 mg NaOH / l g to-you); the elementary composition of C27Hi804, calculated: C 79.79%, H 4.46%; found C 79.25%, H 4.76%.

3. Synthesis of 9,9-bis- (4-carboxyphenyl) -fluorene chloride.

4.0 g of 9,9-bis- (4-carboxyphenyl) fluorene and 7.0 ml of thionyl chloride are charged to a flask equipped with a reflux condenser with a calcium chloride tube. The contents of the flask are heated at the boiling point of thionyl chloride until complete dissolution of the dicarboxylic acid (10 hours). Excess thionyl chloride is then distilled off and the acid chloride is recrystallized from dichloroethane. The yield of acid chloride after recrystallization 3.6 g, so pl. 155-157 ° C; elemental composition C27Hi6Cl2O2, calculated: C 73.16%; H 3.64%, C1 15.99%; found: C 73.10%; H 3.60%; C1 15.79%.

4. Synthesis of 9,9-bis- (4carboxyphenyl) -fluorene methyl ester.

In a round bottom flask, equipped with a reflux condenser with a calcium chloride tube, load 3.0 g of 9,9-bis- (4-carboxyfepyl) -fluorene, 10 ml of absolute methanol and 0.1 ml of concentrated sulfuric acid. The esterification reaction is carried out at the boiling point of methanol for 10 hours. The precipitate formed after cooling is filtered off, washed with cold water until complete removal of sulfuric acid and substantial g at a temperature of –80 ° C.

The yield of the product thus obtained is 3.0 g; m.p. 178-180 ° C; elementary

composition C29H22O4, calculated: C 80.17%; H 5.10%; found: C 80.0% H 5.05%.

5. Synthesis of dihydrazide 9,9-bis- (4-carboxyphenyl) -fluorene. In a round bottom flask, equipped with a reflux condenser, load 3.6 g of methyl ester of 9,9-bis- (4-carboxyphenyl) -fluorene, 25 ml of methanol and 10 ml of hydrazine hydrate. The solution is incubated for 20 hours at boiling, and then cooled to room temperature. The precipitate formed on cooling is filtered off, washed with water until neutral and recrystallized from 40 ml of aqueous ethanol. The output of dihydrazide after recrystallization of 3.2 g;

m.p. 286-287 ° C; elementary composition 56

C27H22N402: Calculated: C, 74.64%; H5.10%; due to the fact that fluorenone condensate N is 12.89%; Found: C, 74.50%; H 5.0%; rut with toluene in the presence of polyphosphorus N 12.85 |% of a. acid and subsequent oxidation according to Invention 5 of the desired product, or by transformation

The method of obtaining the 9,9-bis- (4-carboxy-eqing acid chloride or ester, yl) -fluorene or its derivatives, moli or dihydrazide by known methods.

440365

of radiated 9,9-ditolylfluoren and or of the obtained dicarboxylic acid in accordance