Isatin → Tryptanthrin

Participants

Reaction Steps

11 g (0.068 mol) of the isato acid anhydride of the aforesaid formula (1a-1), and 10 g (0.068 mol) of isatine represented by the following formula: ##STR75## and 20 ml of pyridine were heated under reflux for 6 hours in a 200 ml eggplant type flask to be reacted. After the reaction solution was cooled, a crystal precipitated in the reaction solution was filtered off to give 6.46 g (yield: 38%) of tryptanthrine represented by the following formula. ##STR76##

Provenance & Evidence