The water soluble cobalt(III) porphyrin complex (CoTCPP) was employed as an efficient catalyst for the synthesis of the biologically active natural product tryptanthrin. The reaction proceeded under mild conditions in aqueous media at room temperature from various isatoic anhydride and isatin derivatives. The advantages of these reactions were excellent yields, short reaction times and a recoverable catalyst.
Cobalt (III)-porphyrin Complex (CoTCPP) as an efficient and recyclable homogeneous catalyst for the synthesis of tryptanthrin in aqueous media | Request PDF. Available from: https://www.researchgate.net/publication/287148944_Cobalt_III-tryptanthrin_in_aqueous_media