1: 40 percent / LiAlH4 / diethyl ether / 1 h / Ambient temperature 2: 82 percent / 4-(dimethylamino)pyridine, N,N-dicyclohexylcarbodiimide / CH2Cl2 / Ambient temperature 3: 1.) LDA, HMPA / 1.) THF, -78 deg C, 40 min, 2.) THF, reflux, overnight View Scheme

1: 1) O3, 2) Me2S / 1) CH2Cl2, -78 degC, 2) room temp., 1 h 2: oxalyl chloride, pyridine / benzene / 6 h / Ambient temperature 3: pyridine, 4-(dimethylamino)pyridine / CH2Cl2 / 6 h / Ambient temperature 4: 90.5 percent / ZnCl2, K / tetrahydrofuran / 1) room temp., 1 h, 2) 40-50 degC, 1 h 5: 10 percent / tetrahydrofuran / 1) -78 degC, 2) -20 degC, 30 min View Scheme

2: tetrahydrofuran / -78 °C View Scheme

KOCl in dichloromethane; water T=0°C;

potassium hydroxide; silver nitrate in ethanol; water T=0°C; 2 h;

tetrafluoroboric acid; mercury(II) oxide in tetrahydrofuran 24 h;

tetrafluoroboric acid; mercury(II) oxide in tetrahydrofuran Ambient temperature;

1: 172 mg / tBuOK / Pd(dppe) / tetrahydrofuran / 6 h / 50 °C 2: pTsOH / cyclohexane / 2 h / Heating View Scheme

1: 69 percent / tetrahydrofuran / 1.5 h / -78 - -10 °C 2: 51 percent / aq. 48percent HBF4, red HgO / tetrahydrofuran / 24 h View Scheme

toluene-4-sulfonic acid in cyclohexane 2 h; Heating; Yield given;