Entry Catalyst Time (min) Yield (%)b
Product (I) Product (II)
1 N-sulfonic acid poly(4-vinylpyridinium) chloride (NSPVPC) 120 48 52
2 N-sulfonic acid poly(4-vinylpyridinium) hydrogen sulfate (NSPVPHS) 15 0 94
aReaction conditions: 4-chloro-benzaldehyde, 1.0 mmol; 2-naphthol 2.0 mmol; NSPVPC or NSPVPHS catalyst, 10 mg; 60 °C and under solvent-free conditions
b Isolated yield.
Table 3: The effect of exchange anion chloride with hydrogen sulfate on the synthesis of 14-(4-chlorophenyl)-14H-dibenzo [a,j]xanthenea.