1: 2-bromo-2-methyl-propionic acid With 1,1'-carbonyldiimidazole in dichloromethane 0.25 h; Heating; 2: butan-1-ol in dichloromethane 2 h; Heating; Further stages.;

1: With lithium diisopropyl amide in tetrahydrofuran T=-78°C; 1 h; Inert atmosphere; 2: With 1,2-dibromo-1,1,2,2-tetrafluoroethane in tetrahydrofuran T=20°C; 3 h; Inert atmosphere;

pyridine in chloroform 1 h;