1: ethyl acetate With copper(I) bromide dimethylsulfide complex; lithium diisopropyl amide in tetrahydrofuran T=-78°C; 0.5 h; 2: [2E,6E]-acetic acid 8-bromo-3,7-dimethyl-octa-2,6-dienylester in tetrahydrofuran T=-78°C; 80 h; Further stages.;

lithium chloride in N,N-dimethyl-formamide T=173°C; 0.5 h; Yields of byproduct given;

sodium chloride in water; dimethyl sulfoxide 1.) 160 deg C, 7 h, 2.) 23 deg C, 12 h; Yield given;

1: tert-butyl hydroperoxide, SeO2 / CH2Cl2 / 3 h / 10 °C 2: 94.5 percent / CBr4, triphenylphophine / diethyl ether / 24 h / 4 °C 3: NaH / dimethylformamide / 1.) 60 deg C, 4.5 h, 2.) 12 h, 23 deg C 4: NaCl, H2O / dimethylsulfoxide; H2O / 1.) 160 deg C, 7 h, 2.) 23 deg C, 12 h View Scheme

1: NaH / dimethylformamide / 1.) 60 deg C, 4.5 h, 2.) 12 h, 23 deg C 2: NaCl, H2O / dimethylsulfoxide; H2O / 1.) 160 deg C, 7 h, 2.) 23 deg C, 12 h View Scheme

1: 94.5 percent / CBr4, triphenylphophine / diethyl ether / 24 h / 4 °C 2: NaH / dimethylformamide / 1.) 60 deg C, 4.5 h, 2.) 12 h, 23 deg C 3: NaCl, H2O / dimethylsulfoxide; H2O / 1.) 160 deg C, 7 h, 2.) 23 deg C, 12 h View Scheme

potassium carbonate 1.41667 h;