1: With tert.-butyl lithium in tetrahydrofuran; pentane T=-78°C; 0.166667 h; 2: With boric acid trimethyl ester T=20°C; pH=2; 1 h;

n-butyllithium; boric acid trimethyl ester; potassium tert-butylate 1.) THF, -78 deg C, hexane, -40 deg C, 30 min, -78 deg C; 2.) THF, -78 deg C, 4 h, 0 deg C; Multistep reaction;