Sodium Hydroxide → Crystal Violet lactone

Participants

Reaction Steps

To a 500 ml autoclave, 17.1 g of 2-[4,4'-bis(dimethylamino) benzhydryl]-5-dimethylaminobenzoic acid was charged and dispersed by adding 150 g of water. To the dispersion obtained, 3.4 g of activated carbon; SHIRASAGI-C and 1.63 g of a 49% aqueous NaOH solution were added and reacted at 100° C. for 3 hours under increased air pressure of 15 kg/cm2. After finishing the reaction, the reaction mass was treated by the same procedures as carried out in Example 1 to obtain 16.1 g of desired 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophthalide. The yield was 95%. Formation of by-product in the reaction was 1.3%. Selectivity of reaction was 98.7%.

Provenance & Evidence