Highly Efficient Synthesis of 1-Thioamidoalkyl-2-naphthols and 14-Aryl-14H-dibenzo[a,j]xanthenes using a Novel Ionic Liquid: Catalyst Preparation, Characterization and Performing the Reactions

Atefeh Saadat (Department of Chemistry, Payame Noor University, PO BOX 19395-3697, Tehran)
Abdolkarim Zare (Department of Chemistry, Payame Noor University, PO BOX 19395-3697, Tehran)
Fatemeh Jamadi (Department of Chemistry, Payame Noor University, PO BOX 19395-3697, Tehran)
Maasoomeh Abdolalipour-Saretoli (Department of Chemistry, Payame Noor University, PO BOX 19395-3697, Tehran)

Bulletin of Chemical Reaction Engineering & Catalysis
2018: BCREC Volume 13 Issue 2 Year 2018 (August 2018)

In this work, a novel Brønsted acidic ionic liquid namely triethylaminium-N-sulfonic acid trifluoroacetate {[TEASA][TFA]} has been synthesized by the reaction of NEt3 with ClSO3H, and then with CF3CO2H. The ionic liquid has been characterized by studying its spectroscopic data (1H and 13C NMR, FT-IR, and mass spectra). Afterward, it has been utilized as a highly effective and general catalyst to promote the following organic reactions in solvent-free conditions: (i) the production of 1-thioamidoalkyl-2-naphthols from arylaldehydes, 2-naphthol and thioacetamide, and (ii) the preparation of 14-aryl-14H-dibenzo[a,j]xanthenes from arylaldehydes and 2-naphthol. It is noteworthy that [TEASA][TFA] has catalyzed the reactions under milder conditions relative to most of the reported methods. Moreover, it afforded the both products in higher yields with respect to most of the previous works.