An efficient synthesis of medicinally important indole based triarylmethanes by using propylphosphonic anhydride (T3P^®)

Abstract

We have developed an economical and efficient method for the synthesis of medicinally and synthetically important indole-based triarylmethanes by using indoles and benzhydrols in the presence of propylphosphonic anhydride (T3P^®). This methodology is an alternate approach for the C–C bond formation with good to excellent yields. In this T3P-mediated dehydration approach, the by-product is highly soluble in water, so that it can be done at larger scale also. In addition to that this efficient protocol has several advantages such as mild reaction conditions, short reaction time and operational simplicity. We have successfully synthesized pyrrole, imidazothiadiazole and imidazolo pyridine based triarylmethanes also.

Graphical Abstract

Keywords:

• Alcohols
• nitriles
• N-substituted amides
• propylphosphonic anhydride (T3P^®)
• solvent-free condition

Acknowledgments

We thank NMR facility, Institute of Excellence, University of Mysore, Manasagangotri, Mysore, India for spectral data.

Additional information

Funding

The author is thankful to financial support from the DBT Glue Grant [No. BT/PR23078/MED/29/1253/2017] dated: 22/03/2018 and VGST [K-FIST (L1)] Grant [No. KSTePS/VGST/K-FIST (L1)/2017-18/GRD-681/79/2018-2019] dated: 17/09/2018; and Minor Research Project U.O. [NO: DV6/375/MRP/2017-18], dated: 12/02/2018 is gratefully acknowledged.