1.1: sodium hydride / tetrahydrofuran; mineral oil / 0.17 h / 0 - 25 °C 1.2: 1 h / 0 - 25 °C 2.1: tetrabutyl ammonium fluoride / tetrahydrofuran / 1 h / 25 °C / |Molecular sieve; |Inert atmosphere View Scheme

in tetrahydrofuran; diethyl ether T=-78 - 20°C; 1 h;