pyridinium p-toluenesulfonate in dichloromethane T=20°C; Substitution; 23 h;

1: 1,3-Dithiane With n-butyllithium in tetrahydrofuran; hexane T=-78 - -28°C; 2.5 h; 2: 4-chloro-1-(tetrahydropyran-2-yl-oxy)-n-butane in tetrahydrofuran; hexane T=-78°C; 2 h; Further stages.;

1: p-TsOH / benzene / Heating 2: p-TsOH View Scheme

n-butyllithium in tetrahydrofuran

1: 79 percent / BF3*OEt2 / CHCl3 / 7 h / Ambient temperature 2: 80 percent / toluene-p-sulfonic acid / CH2Cl2 / 6 h / Ambient temperature View Scheme

boron trifluoride diethyl etherate in dichloromethane 0.666667 h; Ambient temperature;

1: methanol / 4 h / Ambient temperature 2: 1.) DMSO, oxalyl chloride, 2.) Et3N / 1.) CH2Cl2, -70 deg C, 40 min, 2.) CH2Cl2, from -70 deg C to -5 deg C, 2 h 3: 91 percent / benzene / 6.5 h / Heating 4: 97 percent / sodium borohydride, cerium(III) chloride heptahydrate / ethanol / 0.67 h 5: 95 percent / pyridine / Ambient temperature 6: 36 percent / KH2PO4, K2HPO4, water / acetone / 12 h / Ambient temperature; lipase PS "Amano" 7: 93 percent / HgCl2, CaCO3, water / acetonitrile / 7 h / Heating 8: benzene 9: benzene / 3 h / Heating 10: H2, AcOH / 10percent Pd/C / 18 h / 760 Torr / Ambient temperature 11: Et3N / tetrahydrofuran; benzene / 1 h / Ambient temperature 12: 91 percent / NaIO4, KMnO4, KH2PO4, K2HPO4 / H2O; acetone / 3 h / Ambient temperature 13: 80 percent / 4 N HCl in dioxane / 1 h / Ambient temperature View Scheme

methanol 4 h; Ambient temperature; Yield given;