Tandem carbon–carbon bond insertion and intramolecular aldol reaction of benzyne with aroylacetones: novel formation of 4,4′-disubstituted 1,1′-binaphthols
An efficient route to 4-aryl-2-naphthols from arynes and aroylacetones was developed by carbon-carbon bond insertion followed by an intramolecular aldol reaction and dehydration. Benzyne derived from 2-(trimethylsilyl)phenyl triflate reacted with benzoylacetones in refluxing acetonitrile to give 4-aryl-2-naphthols and 3-aryl-1-naphthols.
A Ru(II)-catalyzed coupling of various α-carbonyl phosphoniums with sulfoxoniumylides has been realized for the facile synthesis of 1-naphthols in good to excellent yields. This oxidant-free transformation proceeds through Ru-catalyzed C–H activation of phosphoniums, Ru-carbene insertion, and intramolecular Wittig reaction processes.