1: (methoxymethyl)-triphenylphosphonium chloride With n-butyllithium in tetrahydrofuran; hexane T=0°C; 1 h; Inert atmosphere; 2: 4-phenyl-3-methyl-2-butanone in tetrahydrofuran; hexane T=0 - 20°C; Inert atmosphere; 3: With hydrogenchloride in tetrahydrofuran; water T=90°C; 2 h; Inert atmosphere;