Pyrrole synthesis method using juice catalyst

A method of making an N-substituted pyrrole, comprising:

• reacting an amine of formula (5),
• with a compound of formula (6),
• in the presence of a juice catalyst from a fruit of a plant in the genus Malus, to form a compound of formula (4),
• wherein R4, R5, R6, and R7 are each independently a hydrogen, an optionally substituted alkyl, or an optionally substituted aryl;
• wherein R8 is an aryl group;
• wherein greater than 70 mol % of the total number of moles of organic acid present in the juice are malic acid;
• and
• wherein the reacting is performed at 50 to 75° C. for 5 to 10 hours.