potassium hexamethyldisilazane in tetrahydrofuran byproducts: KCl; under Ar atm. to soln. KHDMS in THF ketone in THF was added dropwise at 0°C for 30 min, soln. chlorobis(dialkylamino)borane in THF was added and stirred at room temp. for 1 h; soln. was cenrifugated, ppt. was filtered, volatiles were removed in vacuo;

in tetrahydrofuran T=50°C; 5 h;