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New asymmetric dimers, N,N’-dialkyl-4’-hydroxy-4-oxo-2,2’,3,3’-tetrahydro-2,2’- diphenyl-4,4’-quinolones 3a-f were synthesized through the dehydration and dealcoholation of N-alkylanilines and ethyl benzoylacetate. Dimers 3a-f were identified by NMR, IR and GC-MS. A series of dimer 3a-f has been synthesized using acid-catalyzed one-pot reaction that involved the condensation, cyclization and dimerization. Similarly, the 6,6’-methoxy (or 7,7’-methoxy) substituted dimers were prepared from N-alkyl-meta-(or para)-anisidines. Formation of dimers was undertaken with p-toluenesulfonic acid (p-TSA) at 90~110℃ in toluene for 2~6 hours over the Dean-Stark apparatus.
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