oxalic acid in methanol T=23°C; 20 h;

1: 90 percent / copper bronze / dimethylformamide / 22 h / 108 °C 2: 95 percent / magnesium monoperoxyphthalate / H2O; acetonitrile / 2 h / 50 °C 3: 95 percent / imidazole / dimethylformamide / 2 h / 25 °C 4: 97 percent / diisobutylaluminum hydride / toluene / 1 h / -70 °C 5: 1) Mg 6: 94 percent / oxalic acid / methanol / 20 h / 23 °C View Scheme

1: pyridinium p-toluenesulfonate / toluene / 0.75 h / 70 °C 2: 90 percent / copper bronze / dimethylformamide / 22 h / 108 °C 3: 95 percent / magnesium monoperoxyphthalate / H2O; acetonitrile / 2 h / 50 °C 4: 95 percent / imidazole / dimethylformamide / 2 h / 25 °C 5: 97 percent / diisobutylaluminum hydride / toluene / 1 h / -70 °C 6: 1) Mg 7: 94 percent / oxalic acid / methanol / 20 h / 23 °C View Scheme

1: 1) (-)-chlordiisopinocampheylborane, 2) 5 M aq. NaOH / 1) THF, a) 0 deg C, 4 h, b) 0-5 deg C, 2) methanol, water, 23 deg C, 1.5 h 2: pyridinium p-toluenesulfonate / toluene / 0.75 h / 70 °C 3: 90 percent / copper bronze / dimethylformamide / 22 h / 108 °C 4: 95 percent / magnesium monoperoxyphthalate / H2O; acetonitrile / 2 h / 50 °C 5: 95 percent / imidazole / dimethylformamide / 2 h / 25 °C 6: 97 percent / diisobutylaluminum hydride / toluene / 1 h / -70 °C 7: 1) Mg 8: 94 percent / oxalic acid / methanol / 20 h / 23 °C View Scheme

1: 95 percent / magnesium monoperoxyphthalate / H2O; acetonitrile / 2 h / 50 °C 2: 95 percent / imidazole / dimethylformamide / 2 h / 25 °C 3: 97 percent / diisobutylaluminum hydride / toluene / 1 h / -70 °C 4: 1) Mg 5: 94 percent / oxalic acid / methanol / 20 h / 23 °C View Scheme

1: 95 percent / imidazole / dimethylformamide / 2 h / 25 °C 2: 97 percent / diisobutylaluminum hydride / toluene / 1 h / -70 °C 3: 1) Mg 4: 94 percent / oxalic acid / methanol / 20 h / 23 °C View Scheme

1.1: 96 percent / cesium carbonate / dimethylformamide / 2 h / 50 °C 2.1: 91 percent / 2-methyl-2-butene; aq. sodium chlorite; NaH2PO4 / 2-methyl-propan-2-ol / 4 h / 20 °C 3.1: oxalyl chloride / dimethylformamide; CH2Cl2 / 18 h / 20 °C 4.1: 1.6 g / 2-mercaptopyridine oxide sodium salt; BrCCl3; AIBN / 0.08 h / Heating 5.1: 77 percent / copper bronze / dimethylformamide / 20 h / 100 °C 6.1: 92 percent / imidazole / dimethylformamide / 20 °C 7.1: t-BuLi / pentane / 0.5 h / -78 °C 7.2: 53 percent / pentane; tetrahydrofuran / 0.5 h / -78 °C 8.1: 75 percent / NaBH3CN; Cl2CHCO2H / various solvent(s) / 0.5 h / -25 °C 9.1: 67 percent / 450 °C / 0 Torr 10.1: 75 percent / H2 / Pt/C / ethyl acetate / atmospheric pressure 11.1: 80 percent / m-chloroperbenzoic acid / CH2Cl2 / 1 h / 20 °C 12.1: 85 percent / n-Bu4NF / tetrahydrofuran / 2 h / 0 °C View Scheme

1.1: t-BuLi / pentane; diethyl ether / 1 h / -78 °C 1.2: ClTi(O-i-Pr)3 / diethyl ether; pentane; hexane / -40 - 0 °C 1.3: 91 percent / tetrahydrofuran; diethyl ether; various solvents / 4.5 h / 0 - 20 °C 2.1: 78 percent / 4 Angstroem molecular sieves; 4-methoxymorpholine N-oxide; tetrapropylammonium perruthenate / CH2Cl2 / 5 h / 20 °C 3.1: t-BuLi / pentane / 0.5 h / -78 °C 3.2: 53 percent / pentane; tetrahydrofuran / 0.5 h / -78 °C 4.1: 75 percent / NaBH3CN; Cl2CHCO2H / various solvent(s) / 0.5 h / -25 °C 5.1: 67 percent / 450 °C / 0 Torr 6.1: 75 percent / H2 / Pt/C / ethyl acetate / atmospheric pressure 7.1: 80 percent / m-chloroperbenzoic acid / CH2Cl2 / 1 h / 20 °C 8.1: 85 percent / n-Bu4NF / tetrahydrofuran / 2 h / 0 °C View Scheme

1.1: oxalyl chloride / dimethylformamide; CH2Cl2 / 18 h / 20 °C 2.1: 1.6 g / 2-mercaptopyridine oxide sodium salt; BrCCl3; AIBN / 0.08 h / Heating 3.1: 77 percent / copper bronze / dimethylformamide / 20 h / 100 °C 4.1: 92 percent / imidazole / dimethylformamide / 20 °C 5.1: t-BuLi / pentane / 0.5 h / -78 °C 5.2: 53 percent / pentane; tetrahydrofuran / 0.5 h / -78 °C 6.1: 75 percent / NaBH3CN; Cl2CHCO2H / various solvent(s) / 0.5 h / -25 °C 7.1: 67 percent / 450 °C / 0 Torr 8.1: 75 percent / H2 / Pt/C / ethyl acetate / atmospheric pressure 9.1: 80 percent / m-chloroperbenzoic acid / CH2Cl2 / 1 h / 20 °C 10.1: 85 percent / n-Bu4NF / tetrahydrofuran / 2 h / 0 °C View Scheme

1.1: 77 percent / copper bronze / dimethylformamide / 20 h / 100 °C 2.1: 92 percent / imidazole / dimethylformamide / 20 °C 3.1: t-BuLi / pentane / 0.5 h / -78 °C 3.2: 53 percent / pentane; tetrahydrofuran / 0.5 h / -78 °C 4.1: 75 percent / NaBH3CN; Cl2CHCO2H / various solvent(s) / 0.5 h / -25 °C 5.1: 67 percent / 450 °C / 0 Torr 6.1: 75 percent / H2 / Pt/C / ethyl acetate / atmospheric pressure 7.1: 80 percent / m-chloroperbenzoic acid / CH2Cl2 / 1 h / 20 °C 8.1: 85 percent / n-Bu4NF / tetrahydrofuran / 2 h / 0 °C View Scheme