1: 1.) Mg / 1.) Et2O, r.t., 2.) Et2O, -40 deg C, 20 min 2: 61 percent / diethyl ether; tetrahydrofuran / 1.) r.t., overnight, 2.) reflux View Scheme

in tetrahydrofuran; diethyl ether 1.) -20 deg C to r.t., overnight, 2.) reflux;

1.) Et2O, -60 deg C, 25 min, 2.) THF, -60 deg C to r.t.; Yield given. Multistep reaction. Yields of byproduct given;