4,4'-(9H-Fluoren-9-ylidene)bis(2-chlorobenzenamine) synthesis

Yield:107934-68-9 92.8%

Reaction Conditions:

Stage #1: 2-Chloroanilinewith sulfuric acid in ethylene glycol at 20 - 50; for 0.5 h;
Stage #2: 9-fluorenone in ethylene glycol at 140;

Steps:

2 This example is a method for preparing 9,9-bis[2-chloro-4-aminophenyl]fluorene, which is as follows:

General procedure: Add 36.0g (0.28mol) of 3-chloroaniline and 50mL of ethylene glycol to a 250mL three-necked flask equipped with mechanical stirring. After mixing well, slowly add 4.9g of concentrated sulfuric acid at a temperature of ≤50 ° C, and stir at room temperature for 0.5h. Then, add 18.0g (0.1mol) of 9-fluorenone, mix at room temperature first, then raise the temperature to 150 ± 1 ° C to conduct the condensation reaction. The reaction ends when the 9-fluorenone content is <0.1%. After the reaction, the reaction system was cooled to room temperature, 36 mL of a 40 wt% sodium hydroxide aqueous solution was added, stirred for 1.5 h, and filtered. The filter cake was slurried with 36 mL of water at room temperature, filtered, and the cake was dried to obtain 41.0 g of crude product and 50 mL of toluene. Recrystallization, filtration, and drying of the filter cake gave 39.8 g of the target product 9,9-bis [2-chloro-4-aminophenyl] fluorene with a yield of 95.4% and a purity of 99.5%.

References:

CN110437078,2019,A Location in patent:Paragraph 0020-0023