lithium perchlorate in tetrahydrofuran T=50°C; 24 h;

tert.-butyl lithium Yield given. Yields of byproduct given. Title compound not separated from byproducts;

methyllithium 1) THF, -95 deg C, 10 min 2) -95 deg C, 20 min; Yield given. Multistep reaction. Yields of byproduct given. Title compound not separated from byproducts;