potassium hydroxide Behandeln des in Methanol geloesten Reaktionsprodukts mit Dimethylsulfat und wss. KOH, zuletzt auf dem Dampfbad;

1: 84 percent / K2CO3 / acetone / 45 h / Heating 2: 94 percent / Br2 / CCl4 / 0 °C View Scheme

Yield given. Multistep reaction;

1: 88 percent / EtMgBr / tetrahydrofuran 3: H2 / 10percentPd-C / acetic acid; aq. HClO4 / 4 h / 60 °C / 2585.7 Torr 4: PPE / CH2Cl2 / 0.5 h / Heating 5: 1.) H2SO4, 2.) o-chloranil / 1.) toluene, reflux, 2h, 2.) reflux, 1h 6: 96 percent / NaBH4 / 1,2-dimethoxy-ethane / 3 h / Heating 7: 95 percent / 150 - 215 °C 8: 87 percent / KOH / acetone / Ambient temperature View Scheme

ethylmagnesium bromide in tetrahydrofuran

1: 88 percent / EtMgBr / tetrahydrofuran 3: H2 / 10percentPd-C / acetic acid; aq. HClO4 / 4 h / 60 °C / 2585.7 Torr 4: PPE / CH2Cl2 / 0.5 h / Heating 5: 1.) H2SO4, 2.) o-chloranil / 1.) toluene, reflux, 2h, 2.) reflux, 1h View Scheme

1: 88 percent / EtMgBr / tetrahydrofuran 3: H2 / 10percentPd-C / acetic acid; aq. HClO4 / 4 h / 60 °C / 2585.7 Torr 4: PPE / CH2Cl2 / 0.5 h / Heating 5: 1.) H2SO4, 2.) o-chloranil / 1.) toluene, reflux, 2h, 2.) reflux, 1h 6: 96 percent / NaBH4 / 1,2-dimethoxy-ethane / 3 h / Heating View Scheme