Solvent-free one-pot synthesis of amidoalkyl naphthols catalyzed by silica sulfuric acid

An efficient, inexpensive, and mild method for the synthesis of amidoalkyl naphthols, catalyzed by 'silica sulfuric acid' (SSA), was elaborated under solvent-free conditions at room temperature. Various amidoalkyl naphthols were synthesized in high yields from aromatic or aliphatic aldehydes, alpha- or beta- naphthols, and amides or urea or thiourea.