lithium hydroxide hydrate in tetrahydrofuran; water T=20°C; 4 h;

1: 1.) pyridine / 1.) CH2Cl2, 0.5h, 0 deg C, 2.) CH2Cl2, RT, 18h 2: methanol / 3 h / Heating 3: 92 percent / Ph3P / diethyl ether View Scheme