1: Methyltriphenylphosphonium bromide With n-butyllithium in diethyl ether; hexane T=20°C; 0.5 h; Inert atmosphere; 2: (+-)-4-tert.-Butyl-2,2-dimethyl-cyclohexanon in diethyl ether; hexane T=20°C; Wittig reaction; Inert atmosphere;