Reactivity of arylethynyl(phenyl)iodonium salts towards some 1,3-dipoles. X-Ray molecular structure of 3-mesityl-5-phenylisoxazol-4-yl(phenyl)iodonium toluene-p-sulphonate

Abstract

Three arylethynyl(phenyl)iodonium salts reacted as 1,3-dipolarophiles with two nitrite oxides to afford phenyl(substituted isoxazolyl)iodonium salts; these gave iodoisoxazoles on reaction with nucleophiles. Phenyl(phenylethynyl)iodonium toluene-p-sulphonate reacted in the same way with nitrones but the resulting phenyl(substituted isoxazolinyl)iodonium salts, with one exception, were difficult to isolate because of ready hydrolysis. The crystal structure of 3-mesityl-5-phenylisoxazol-4-yl(phenyl)iodonium toluene-p-sulphonate has been determined.