1: 75 percent / 18-crown-6-ether, KOH / petroleum ether / 10 h / 90 - 110 °C 2: 1) lithium amide / 1) THF, 30-35 deg C, 0.5 h; 2) HMPTA, 20 deg C, 2 h. 3: hydrogen, quinoline / 5percent Pd/BaSO4 / hexane / 20 °C View Scheme

1: 75 percent / 18-crown-6-ether, KOH / petroleum ether / 10 h / 90 - 110 °C 2: 1) n-BuLi / 1) benzene + THF, 20 deg C, 1 h; 2) HMPTA, 20 deg C, 6 h. View Scheme

1: 75 percent / 18-crown-6-ether, KOH / petroleum ether / 10 h / 90 - 110 °C 2: 1) n-BuLi / 1) benzene + THF, 20 deg C, 1 h; 2) HMPTA, 20 deg C, 6 h. 3: 97 percent / LiAlH4 / tetrahydrofuran; bis-(2-methoxy-ethyl) ether / 10 h / 140 °C View Scheme

1: 75 percent / 18-crown-6-ether, KOH / petroleum ether / 10 h / 90 - 110 °C 2: 1) n-BuLi / 1) benzene + THF, 20 deg C, 1 h; 2) HMPTA, 20 deg C, 6 h. 3: 95 percent / hydrogen, quinoline / 5percent Pd/BaSO4 / hexane / 20 °C View Scheme

potassium hydroxide; 18-crown-6 ether in Petroleum ether T=90 - 110°C; 10 h;

1: 55 percent / KOH; 18-crown-6 / heptane / 22 h 2: pyridinium p-toluenesulfonate View Scheme

1: 75 percent / 18-crown-6-ether, KOH / petroleum ether / 10 h / 90 - 110 °C 2: 1) lithium amide / 1) THF, 30-35 deg C, 0.5 h; 2) HMPTA, 20 deg C, 2 h. View Scheme