Efficient generation and trapping of acylbenzynes from hypervalent iodine compounds

[5-Acyl-2-(trimethylsilyl)phenyl]iodonium triflates were prepared for the generation of benzynes bearing ketone function. Treatment of the iodonium triflates with Bu4NF in CH2Cl2 in the presence Of furan at room temperature gave 6-acyl-1,4-epoxy-1,4-dihydronaphthalenes in high yields. The mild conditions and the tolerance of the ketone function on benzyne generation are attributable to the advantage of hypervalent iodine compounds. (c) 2006 Elsevier Ltd. All rights reserved.