SU499263A1 - Method for preparing 2- (-carbazolyl) -ethyl vinyl ethers - Google Patents

Description

The invention relates to a process for the preparation of new 2- (L-carbazolyl) ethyl vinyl ethers, which are the starting materials for the preparation of polymers. In the literature, there is a known method for producing 2 (1-pyrrole) -ethyl vinyl ether by reacting pyrrolkali with 2-chloroethylvinyl ether, and preliminary preparation of pyrrolkali by fusion of pyrrole with caustic potash is necessary. For the purpose of one-step preparation of 2- (Ncarbazolyl) -ethyl vinyl ethers of the general formula C112 CH70-CH CH2 where RI and RI are the same or different and denote hydrogen, halogen, nitro group, a carbazole derivative of the general formula G is suggested. , react with 2-haloethyl vinyl ether with heating, preferably at the boiling point of the reaction mass, in an organic solvent, such as acetone, in the presence of a base, such as caustic potash, followed by separation of the target product These compounds can be used as monomers in the preparation of polymers. Example 1. In a round bottom flask equipped with a stirrer, a thermometer, an addition funnel, 3.34 g (0.02 mol) of carbazole, 15 ml of acetone, 4.7 ml (0.04 mol) of 2-chloroethyl vinyl ether and 2.24 g (0.04 mol) of powdered potassium hydroxide. The reaction mixture is heated to boiling and maintained at this temperature until complete disappearance of carbazole. Control over the conversion of carbazole is carried out by TLC on silica gel using a solvent system - acetone: benzene - 5:95. The reaction time is 4 hours. Then the reaction mixture is cooled, poured into water, the precipitated precipitate is filtered off and dried at room temperature to constant weight. Output 4,5 i (95% of theoretical). After one recrystallization from a mixture of isopropanol and WADOI, 3.7 g of 2- (L-carbazolyl) ethylvinyl ether with m.p. 69.5-70 ° C.

Found,%: N 5.7.

CisHisNO.

Calculated,%: N 5.9.

Example 2. According to the method described in example 1, from 3.34 g (0.02 mol) of carbazole, 15 ml of acetone, 3.39 ml (0.04 mol) of 2-bromo ethyl vinyl ether, 2.24 g (0, 04 mol) of potassium hydroxide under the conditions of boiling for 2 hours; 4.5 g (95% of the theoretical) 2- (L-carbazolyl) ethyl vinyl ether are obtained. After one recrystallization from a mixture of propanol - water, the yield of ether equals 3.32 g (70% of the theoretical).

Example 3. In a round bottom flask equipped with a stirrer, a reflux condenser and a thermometer, 4 g (0.02 mol) of 3 chlorocarbazole, 15 ml of methyl ethyl ketone, 4.7 ml (0.04 mol) of 2-chloro ethyl ethyl vinyl ether, 2.24 g (0 , 04 mol) of powdered caustic potash. The mixture is stirred at reflux for 1 hour. This dissolves 3-chlorocarbazole and potassium hydroxide and the mixture turns a light yellow color. The reaction mixture is left overnight at room temperature, and then boiled for 2 hours. The reaction mixture is washed with water until neutral wash water. The organic layer is dried with calcium chloride, the methyl ethyl ketone is distilled off. The precipitated crystals are filtered off. The output of 5.07 g (95% of theoretical). After recrystallization, the yield of 2 - N - (3 - chlorocarbazolyl) methyl vinyl ether is 3.7 g (70.5% of the theoretical) with m.p. 89 ° C.

Found,%: N 5.36.

CieHnNOCL

Calculated,%: N 5.4.

Example 4. According to the method described in example 3 of 4.76 g (0.02 mol) of 3,6-dichlorocarbazole, 15 ml of methyl ethyl ketone, 4.7 ml (0.04 mol) of 2-chloro-ethylvinyl ether, 2.24 g powdered potassium hydroxide at a boiling point of the mixture for 6 hours, 5 g (71% of the theoretical) ethyl vinyl ether of 36-dichlorocarbazole with m.p. 115 ° C.

Found,%: N 4.7.

CieHigNOCU.

Calculated,%: N 4.59.

Example 5. According to the method described in example 1, from 2.5 g of 3-nitrocarbazole, 12.5 ml of acetone, 12 ml of 2-chloroethylvinyl ether, 0.972 g of potassium hydroxide for 2 h get 2.8 g (85% of theoretical) (3-nitro) carbazolyl-ethyl vinyl ether with so pl. 171-172 ° C (one recrystallization from ethanol / acetone).

Found,%: N9.53.

CieHuNgOs.

Calculated,%: N 9.93.

Claims (2)

1. A process for the preparation of 2- (L-carbazolyl) ethyl vinyl ethers of the general formula -E and I СНаСН О-С.Н.СН2 where RI and R2 are the same or different and denote hydrogen, halogen, nitro, about 30, in that the carbazole derivative of the general formula where RI and Rz are as defined above, are reacted with 2-haloethyl vinyl ether when heated in an organic solvent medium, such as acetone, in the presence of a base, such as caustic potash, followed by isolation of the target product by known techniques. 2. The method according to claim 1, characterized in that the process is carried out at the boiling point of the reaction mass.