1: (S)-(+)-1-bromo-2-methylbutane With iodine; magnesium in tetrahydrofuran Inert atmosphereReflux; 2: 5-chloropentyl-1-tosylate With dilithium tetrachlorocuprate in tetrahydrofuran T=-60 - 20°C; Grignard reaction; Inert atmosphere;

pyridine; 4-(N,N-dimethlyamino)pyridine T=0 - 5°C; 2 h;

zinc(II) chloride