1: in benzene 5 h; Heating / reflux; 2: With chloroformic acid ethyl ester in tetrahydrofuran T=-10 - 20°C; 0.0833333 h; 3: With sodium hydroxide; titanium tetrachloride; phosphorous acid trimethyl ester more than 3 stages;

palladium on activated charcoal in 1,3,5-trimethyl-benzene T=190 - 200°C; 0.5 h;

titanium tetrachloride in dichloromethane 36 h; Heating;

1: 1.) n-BuLi / 1.) THF, hexane, 0 deg C, 1 h, 2.) from -78 deg C to RT 2: 94 percent / ethyl chloroformate / CHCl3 / 0.25 h / 0 °C 3: 88 percent / dimethylformamide / 4 h 4: concd H2SO4, H2 / PtO2 / ethanol / 12 h / 2585.7 Torr 5: benzene / 3 h / Heating 6: 93 percent / LiAlH4 / tetrahydrofuran / 5 h / Heating 7: 10 percent Spectr. / MnO2 / CH2Cl2 / 40 h / 23 °C View Scheme

1: concd H2SO4, H2 / PtO2 / ethanol / 12 h / 2585.7 Torr 2: benzene / 3 h / Heating 3: 93 percent / LiAlH4 / tetrahydrofuran / 5 h / Heating 4: 10 percent Spectr. / MnO2 / CH2Cl2 / 40 h / 23 °C View Scheme

1: 94 percent / ethyl chloroformate / CHCl3 / 0.25 h / 0 °C 2: 88 percent / dimethylformamide / 4 h 3: concd H2SO4, H2 / PtO2 / ethanol / 12 h / 2585.7 Torr 4: benzene / 3 h / Heating 5: 93 percent / LiAlH4 / tetrahydrofuran / 5 h / Heating 6: 10 percent Spectr. / MnO2 / CH2Cl2 / 40 h / 23 °C View Scheme

1: 88 percent / dimethylformamide / 4 h 2: concd H2SO4, H2 / PtO2 / ethanol / 12 h / 2585.7 Torr 3: benzene / 3 h / Heating 4: 93 percent / LiAlH4 / tetrahydrofuran / 5 h / Heating 5: 10 percent Spectr. / MnO2 / CH2Cl2 / 40 h / 23 °C View Scheme

manganese(IV) oxide in dichloromethane T=23°C; 40 h; Title compound not separated from byproducts;

1: 78 percent / LAH / tetrahydrofuran / 5 h / 80 °C 2: 80 percent / 10percent Pd/C / 1,3,5-trimethyl-benzene / 0.5 h / 190 - 200 °C View Scheme

1: benzene / 24 h / Heating 2: 1.) ethyl chloroformate; 2.) P(OMe)3; 3.) TiCl4 / 1.) THF, -10 deg C, 5 min; 2.) THF, r.t., 15 h; 3.) CH2Cl2, reflux, 36 h View Scheme