One-Pot Synthesis of 2-Arylindole Derivatives under Transition-Metal-Free Conditions

Abstract

A new and simple method for preparing 2-arylindole derivatives under transition-metal-free conditions has been developed. When N-(2-methyl-3-nitrophenyl)acetamide was treated with 2-fluorobenzaldehydes in the presence of Cs₂CO₃ in DMF at 60 °C, the desired indoles were typically obtained in moderate to good yields (up to 83%). When other aniline substrates were employed, only a Knoevenagel condensation occurred, giving the corresponding diarylethenes in moderate to excellent yields.

Key words

indoles - one-pot synthesis - transition-metal-free synthesis - cascade reaction - Knoevenagel condensation

• References and Notes

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