1: ethyl acetate With lithium diisopropyl amide in tetrahydrofuran T=-78°C; 0.5 h; 2: ethyl 3,3-dimethylhex-5-enoate in tetrahydrofuran T=25°C;

1.1: CuCl / tetrahydrofuran / 0.17 h / -15 °C 1.2: tetrahydrofuran / 2 h / -15 - 25 °C 2.1: 1.93 g / aq. LiCl / dimethylsulfoxide / Heating 3.1: LDA / tetrahydrofuran / 0.5 h / -78 °C 3.2: 15 percent / tetrahydrofuran / 25 °C View Scheme

1.1: 1.93 g / aq. LiCl / dimethylsulfoxide / Heating 2.1: LDA / tetrahydrofuran / 0.5 h / -78 °C 2.2: 15 percent / tetrahydrofuran / 25 °C View Scheme

copper dichloride; dichloro bis(acetonitrile) palladium(II) in 1,2-dichloro-ethane T=70°C;