dipyridinium dichromate in dichloromethane 6 h; Ambient temperature;

1: 96 percent / Ph3P, imidazole, I2 / tetrahydrofuran / -20 deg C, 15 min then RT, 1.5 h 2: 90 percent / PDC / CH2Cl2 / 6 h / Ambient temperature View Scheme

1: 92 percent / LDA / tetrahydrofuran / 2 h / -78 °C 2: 65 percent / CuI, Zn / ethanol; H2O / 0.67 h / sonication View Scheme

lithium diisopropyl amide in tetrahydrofuran T=-78°C; 2 h;

1: 92 percent / LDA / tetrahydrofuran / 2 h / -78 °C 2: 65 percent / CuI, Zn / ethanol; H2O / 0.67 h / sonication 3: 86 percent / Et3N / (Ph3P)2PdCl2 / dimethylformamide / 1 h / 75 °C 4: 97 percent / quinoline, Lindlar catalyst, H2 / hexane / 8 h 5: 96 percent / 2,2,4-trimethyl-pentane / 5 h / Heating; in the dark 6: diethyl ether; tetrahydrofuran / 10 h / Ambient temperature 7: TBAF / tetrahydrofuran / 24 h / Ambient temperature; in the dark View Scheme

1: 92 percent / LDA / tetrahydrofuran / 2 h / -78 °C 2: 65 percent / CuI, Zn / ethanol; H2O / 0.67 h / sonication 3: 86 percent / Et3N / (Ph3P)2PdCl2 / dimethylformamide / 1 h / 75 °C 4: 97 percent / quinoline, Lindlar catalyst, H2 / hexane / 8 h 5: 96 percent / 2,2,4-trimethyl-pentane / 5 h / Heating; in the dark View Scheme

1: 95 percent / n-BulI / hexane; tetrahydrofuran / 1.) -78 deg C, 30 min; 2.) -92 deg C 2: 50 percent / CuI, Zn / ethanol; H2O / 1.33 h / ultrasonically induced reaction View Scheme