Direct Syntheses of Benzofuran-2(3<i>H</i>)-ones and Benzofuran-3(2<i>H</i>)-ones from 1-(2-Hydroxyphenyl)alkan-1-ones by CuBr<sub>2</sub>or CuCl<sub>2</sub>
New syntheses of benzofuran-2(3H)-ones and benzofuran-3(211)-ones from l-(2-hydroxyphenyl)alkan-1-ones via oxidative cyclization by CuBr 2 or CuCl 2 are described. A new synthesis of 1H-isochromene-1,4(3H)-diones via similar procedures is also described.