lithium diisopropyl amide in tetrahydrofuran T=-78°C;

1: hexanoic acid trimethylsilyl ester With lithium hexamethyldisilazane 2: chloro-trimethyl-silane

1: With titanium tetrachloride in hexane; dichloromethane T=-60 - 20°C; 2: With toluene-4-sulfonic acid in hexane; dichloromethane T=20°C; 3 h;