1: 2,5-Dimethyl-hydroxymethyl benzene With sodium hydride in DMF (N,N-dimethyl-formamide) T=20°C; 1.5 h; 2: (1-(methanesulfonyl)piperidin-4-yl)methyl methanesulfonate in DMF (N,N-dimethyl-formamide) T=20°C;