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.

Polysubstituted isocoumarins such as thunberginol A were synthesized by the reaction of substituted 2-(trimethylsilyl)phenyl triflate with trifluoromethylated β-diketones in the presence of CsF. The reaction proceeded via carbon–carbon bond insertion of aryne followed by intramolecular cyclization and CF3 anion extrusion. The –C(···O)CF3 unit has high potential for not only the nucleophilic moiety but also a useful leaving group of CF3.

Novel one-pot synthesis of 2,3-benzodiazepines from aryne precursors was accomplished. Tofisopam, well-known anxiolytics, could be synthesized via C–C bond insertion of 4,5-dimethoxybenzyne with 2-ethyl-1-(3,4-dimethoxyphenyl)butane-1,3-dione, followed by the reaction with hydrazine hydrate in a one-pot operation. This protocol is applicable to the synthesis of other biologically active 2,3-benzodiazepines, such as Girisopam and Nerisopam.

Novel One-Pot Synthesis of Polysubstituted Isocoumarins from Arynes and Trifluoroacetylated -Diketones. -Compound (VIII) is fully demethylated to afford thunberginol A. The latter and xyridine A (X) exhibit antimicrobial, antiallergic, antidiabetic, and anticancer activity. -(OKUMA*, K.; HIRANO, K.; TANABE, Y.; ITOYAMA, R.; MIURA, A.; NAGAHORA, N.; SHIOJI, K.; Chem. Lett. 43 (2014) 4, 492-494, http://dx.

One-Pot Synthesis of 2,3-Benzodiazepines from Arynes and -Diketones. -Compound (VII) represents the benzodiazepine drug Tofisopam. Reduction of the NO 2-group in (IIIa) to an amino group gives the drug Nerisopam. Additionally, by applying this method, Girisopam is synthesized, an analogue of (IIIa) bearing a 3-chlorophenyl instead of the 4-nitrophenyl group. -(OKUMA*, K.; TANABE, Y.; ITOYAMA, R.; NAGAHORA, N.; SHIOJI, K.; Chem. Lett. 42 (2013) 10, 1260-1262, http://dx.