in diethyl ether 2 h; Ambient temperature;

1: 3-iodo-1-(phenylsulfonyl)-1H-indole With lithium diisopropyl amide in tetrahydrofuran; n-heptane; ethylbenzene T=-60°C; 0.166667 h; 2: C8H8O5 in tetrahydrofuran; n-heptane; ethylbenzene T=-60 - 20°C; 1 h;