1: (S)-2-bromo-(1,4)-butanediol With sodium hydride in tetrahydrofuran; mineral oil T=-5°C; 2.5 h; Inert atmosphere; 2: 1-bromomethyl-4-methoxy-benzene in tetrahydrofuran; N,N-dimethyl-formamide; mineral oil T=-5 - 20°C; 2.58333 h; Inert atmosphere;