1: With tert.-butyl lithium in diethyl ether; n-heptane; pentane T=-78 - 0°C; 2.5 h; Inert atmosphere; 2: With methanol in diethyl ether; n-heptane; pentane 3: With 5 Pd/C; hydrogen in ethanol P=760.051 Torr; 44 h;