Synthesis of Metal‐Free Phthalocyanines in Functionalized Ammonium Ionic Liquids

Abstract

A convenient, fast, efficient, and ecofriendly synthesis of metal‐free phthalocyanines from various substituted phthalonitriles in different hydroxyalkylammonium ionic liquids in the presence of 1,8‐diazabicyclo‐[5,4,0]‐undec‐7‐ene (DBU) is reported in moderate yields. The effect of concentration of DBU and temperature on the synthesis of phthalocyanine in N‐(2‐hydroxyethyl)‐N,N‐dimethylbutylammonium bromide ionic liquid has been examined, and the ionic liquid has been recovered and reused conveniently.

Keywords:

• 1,8‐diazabicyclo‐[5,4,0]‐undec‐7‐ene (DBU)
• ionic liquids
• liquid crystals
• metal‐free phthalocyanines
• thermal heating

Acknowledgments

Pratibha Kumari and Shweta Agarwal acknowledge the Council of Scientific and Industrial Research (CSIR), New Delhi, for awards of senior research fellowship and junior research fellowship. S. M. S. Chauhan acknowledges CSIR and the Department of Science and Technology (DST), New Delhi, for financial support.