Synthesis of Cyanophyll with Sulfonic Acidic Ionic Liquid as Catalyst

Cyanophyll was prepared from the reaction of acetal with benzyl alcohol in the presence of sulfonic acidic ionic liquid 1-( 4-sulfonic group) butyl-3-methylimidazole tetrafluoroborate( [4-sulfbmim][BF4 ]) as acidic catalyst. At reaction temperature 20 ℃,the reaction conditions were optimized by orthogonal experiments as follows,molar ratio of benzyl alcohol and acetal is 1 to 8,reaction time 60 min,amount of catalyst 4 g based on benzyl alcohol. The yield of cyanophyll could be 92. 2%. The acidic ionic liquid [4-sulfbmim][BF4]had better catalytic effect compared with H2SO4 even if it is a little weaker in activity,and it could be reused for 6 times without losing of the catalytic activity.