Characterization and application of pyrazinium di(hydrogen sulfate) as a highly ecient catalyst for synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes, 9-aryl-1,8-dioxo-octahydroxanthenes and 1-amidoalkyl/carbamatoalkyl-2-naphthols

In this work, characterization of Bronsted acidic ionic liquid namely pyrazinium di (hydrogen sulfate) fPyH2 (HSO4) 2g using 1H and 13C NMR, mass, thermogravimetry (TG), and derivative thermogravimetry (DTG) data is achieved. Afterward, it is used as a highly efficient, green, and homogeneous catalyst to promote the following organic transformations under solvent-free conditions: (i) the synthesis of 14-aryl-14Hdibenzo [ a, j] xanthenes from 2-naphthol and arylaldehydes, (ii) the preparation of 9-aryl-1, 8- dioxo-octahydroxanthenes by the reaction of dimedone (5, 5-dimethyl-1, 3-cyclohexanedione) with arylaldehydes, and (iii) the synthesis of 1-amidoalkyl/carbamatoalkyl-2-naphthols by the condensation of 2-naphthol with aromatic aldehydes and amide derivatives/alkyl carbamates.