Sulfuric Acid → Coumarin

Participants

Reaction Conditions

Reaction Steps

100 parts of 50% sulfuric acid were charged to a reactor vessel to which 10.8 parts of o-phenylenediamine and 11.4 parts of ethylcyanoacetate were then subsequently added. This mixture was heated to a reflux until all of the o-phenylenediamine disappeared from the system. To this mixture was then added 25.4 parts of the p-formyl-N,N-dipropoxy-m-aminophenol produced in parts B above and the resultant composition was maintained at a temperature of about 90-95° C. for 1 hour. Hydrolysis with aqueous NAOH resulted in a bright yellow coumarin colorant represented by Formula (VII): ##STR8##

Provenance & Evidence