1: trimethylphosphane; sodium hydroxide / water; methanol / 15 h / 40 °C 2: N-ethyl-N,N-diisopropylamine / methanol / 15 h / 0 - 20 °C 3: anhydrous potassium trimethylsilanolate / diethyl ether / 48 h / 20 °C View Scheme

sodium hydroxide in tetrahydrofuran T=20°C; 16 h;

sodium hydroxide; trimethylphosphane in methanol; water T=40°C; 15 h;