1: 85 percent / diisopropylethylamine, dimethylaminopyridine / CH2Cl2 / 3 h / Ambient temperature 2: 98 percent / tetrabutylammonium fluoride / tetrahydrofuran / 2 h / Ambient temperature 3: 75 percent / pyridine / CH2Cl2 / -5 °C 4: 87 percent / sodium methoxide / CH2Cl2; methanol / 0.67 h / 0 °C 6: 65 percent / 2,6-di-tert-butyl-4-methylphenol / o-xylene / 144 h / Heating 7: 95 percent / 6 M HCl / tetrahydrofuran / 19 h / 40 °C 9: 68 percent / n-Bu3SnH, AIBN / toluene / 0.58 h / Heating 10: 94 percent / LAH / tetrahydrofuran / 0.5 h / 0 °C 11: 91 percent / pyridine / Ambient temperature 12: 85 percent / triethylamine / CH2Cl2 / 0.5 h / Ambient temperature 13: 90 percent / LAH / tetrahydrofuran / 0.67 h / 0 °C 14: 1.) oxalyl chloride, dimethylsulfoxide 2.) triethylamine / 1.) CH2Cl2, -10 deg C, 20 min 2.) -10 deg C, 5 min 15: 53 percent / K2CO3 / methanol / 19 h / 100 °C 16: 73 percent / sodium methoxide / methanol / 2 h / Ambient temperature 17: 85 percent / methanesulfonyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 18: 90 percent / NaBH4 / propan-2-ol; CHCl3 / 0.67 h / Ambient temperature 19: 93 percent / aq.HF / acetonitrile / 24 h / Ambient temperature 20: 70 percent / DMAP / 0.33 h / 40 °C 21: 70 percent / Amberlyst A-21 / diethyl ether / 2 h / Ambient temperature 22: 55 percent / n-Bu3SnH, AIBN / toluene / 0.5 h / Heating 23: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 24: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 25: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 26: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 27: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 28: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme

1: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 2: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 3: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 4: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 5: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 6: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme

1: 87 percent / sodium methoxide / CH2Cl2; methanol / 0.67 h / 0 °C 3: 65 percent / 2,6-di-tert-butyl-4-methylphenol / o-xylene / 144 h / Heating 4: 95 percent / 6 M HCl / tetrahydrofuran / 19 h / 40 °C 6: 68 percent / n-Bu3SnH, AIBN / toluene / 0.58 h / Heating 7: 94 percent / LAH / tetrahydrofuran / 0.5 h / 0 °C 8: 91 percent / pyridine / Ambient temperature 9: 85 percent / triethylamine / CH2Cl2 / 0.5 h / Ambient temperature 10: 90 percent / LAH / tetrahydrofuran / 0.67 h / 0 °C 11: 1.) oxalyl chloride, dimethylsulfoxide 2.) triethylamine / 1.) CH2Cl2, -10 deg C, 20 min 2.) -10 deg C, 5 min 12: 53 percent / K2CO3 / methanol / 19 h / 100 °C 13: 73 percent / sodium methoxide / methanol / 2 h / Ambient temperature 14: 85 percent / methanesulfonyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 15: 90 percent / NaBH4 / propan-2-ol; CHCl3 / 0.67 h / Ambient temperature 16: 93 percent / aq.HF / acetonitrile / 24 h / Ambient temperature 17: 70 percent / DMAP / 0.33 h / 40 °C 18: 70 percent / Amberlyst A-21 / diethyl ether / 2 h / Ambient temperature 19: 55 percent / n-Bu3SnH, AIBN / toluene / 0.5 h / Heating 20: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 21: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 22: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 23: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 24: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 25: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme

1: 98 percent / tetrabutylammonium fluoride / tetrahydrofuran / 2 h / Ambient temperature 2: 75 percent / pyridine / CH2Cl2 / -5 °C 3: 87 percent / sodium methoxide / CH2Cl2; methanol / 0.67 h / 0 °C 5: 65 percent / 2,6-di-tert-butyl-4-methylphenol / o-xylene / 144 h / Heating 6: 95 percent / 6 M HCl / tetrahydrofuran / 19 h / 40 °C 8: 68 percent / n-Bu3SnH, AIBN / toluene / 0.58 h / Heating 9: 94 percent / LAH / tetrahydrofuran / 0.5 h / 0 °C 10: 91 percent / pyridine / Ambient temperature 11: 85 percent / triethylamine / CH2Cl2 / 0.5 h / Ambient temperature 12: 90 percent / LAH / tetrahydrofuran / 0.67 h / 0 °C 13: 1.) oxalyl chloride, dimethylsulfoxide 2.) triethylamine / 1.) CH2Cl2, -10 deg C, 20 min 2.) -10 deg C, 5 min 14: 53 percent / K2CO3 / methanol / 19 h / 100 °C 15: 73 percent / sodium methoxide / methanol / 2 h / Ambient temperature 16: 85 percent / methanesulfonyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 17: 90 percent / NaBH4 / propan-2-ol; CHCl3 / 0.67 h / Ambient temperature 18: 93 percent / aq.HF / acetonitrile / 24 h / Ambient temperature 19: 70 percent / DMAP / 0.33 h / 40 °C 20: 70 percent / Amberlyst A-21 / diethyl ether / 2 h / Ambient temperature 21: 55 percent / n-Bu3SnH, AIBN / toluene / 0.5 h / Heating 22: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 23: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 24: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 25: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 26: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 27: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme

1: 55 percent / n-Bu3SnH, AIBN / toluene / 0.5 h / Heating 2: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 3: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 4: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 5: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 6: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 7: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme

2: 62 percent / L-Selectride / tetrahydrofuran / 0.42 h / -78 °C 3: 85 percent / diisopropylethylamine, dimethylaminopyridine / CH2Cl2 / 3 h / Ambient temperature 4: 98 percent / tetrabutylammonium fluoride / tetrahydrofuran / 2 h / Ambient temperature 5: 75 percent / pyridine / CH2Cl2 / -5 °C 6: 87 percent / sodium methoxide / CH2Cl2; methanol / 0.67 h / 0 °C 8: 65 percent / 2,6-di-tert-butyl-4-methylphenol / o-xylene / 144 h / Heating 9: 95 percent / 6 M HCl / tetrahydrofuran / 19 h / 40 °C 11: 68 percent / n-Bu3SnH, AIBN / toluene / 0.58 h / Heating 12: 94 percent / LAH / tetrahydrofuran / 0.5 h / 0 °C 13: 91 percent / pyridine / Ambient temperature 14: 85 percent / triethylamine / CH2Cl2 / 0.5 h / Ambient temperature 15: 90 percent / LAH / tetrahydrofuran / 0.67 h / 0 °C 16: 1.) oxalyl chloride, dimethylsulfoxide 2.) triethylamine / 1.) CH2Cl2, -10 deg C, 20 min 2.) -10 deg C, 5 min 17: 53 percent / K2CO3 / methanol / 19 h / 100 °C 18: 73 percent / sodium methoxide / methanol / 2 h / Ambient temperature 19: 85 percent / methanesulfonyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 20: 90 percent / NaBH4 / propan-2-ol; CHCl3 / 0.67 h / Ambient temperature 21: 93 percent / aq.HF / acetonitrile / 24 h / Ambient temperature 22: 70 percent / DMAP / 0.33 h / 40 °C 23: 70 percent / Amberlyst A-21 / diethyl ether / 2 h / Ambient temperature 24: 55 percent / n-Bu3SnH, AIBN / toluene / 0.5 h / Heating 25: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 26: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 27: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 28: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 29: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 30: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme

1: 91 percent / pyridine / Ambient temperature 2: 85 percent / triethylamine / CH2Cl2 / 0.5 h / Ambient temperature 3: 90 percent / LAH / tetrahydrofuran / 0.67 h / 0 °C 4: 1.) oxalyl chloride, dimethylsulfoxide 2.) triethylamine / 1.) CH2Cl2, -10 deg C, 20 min 2.) -10 deg C, 5 min 5: 53 percent / K2CO3 / methanol / 19 h / 100 °C 6: 73 percent / sodium methoxide / methanol / 2 h / Ambient temperature 7: 85 percent / methanesulfonyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 8: 90 percent / NaBH4 / propan-2-ol; CHCl3 / 0.67 h / Ambient temperature 9: 93 percent / aq.HF / acetonitrile / 24 h / Ambient temperature 10: 70 percent / DMAP / 0.33 h / 40 °C 11: 70 percent / Amberlyst A-21 / diethyl ether / 2 h / Ambient temperature 12: 55 percent / n-Bu3SnH, AIBN / toluene / 0.5 h / Heating 13: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 14: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 15: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 16: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 17: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 18: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme

1: 1.) oxalyl chloride, dimethylsulfoxide 2.) triethylamine / 1.) CH2Cl2, -10 deg C, 20 min 2.) -10 deg C, 5 min 2: 53 percent / K2CO3 / methanol / 19 h / 100 °C 3: 73 percent / sodium methoxide / methanol / 2 h / Ambient temperature 4: 85 percent / methanesulfonyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 5: 90 percent / NaBH4 / propan-2-ol; CHCl3 / 0.67 h / Ambient temperature 6: 93 percent / aq.HF / acetonitrile / 24 h / Ambient temperature 7: 70 percent / DMAP / 0.33 h / 40 °C 8: 70 percent / Amberlyst A-21 / diethyl ether / 2 h / Ambient temperature 9: 55 percent / n-Bu3SnH, AIBN / toluene / 0.5 h / Heating 10: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 11: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 12: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 13: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 14: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 15: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme

1: 53 percent / K2CO3 / methanol / 19 h / 100 °C 2: 73 percent / sodium methoxide / methanol / 2 h / Ambient temperature 3: 85 percent / methanesulfonyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 4: 90 percent / NaBH4 / propan-2-ol; CHCl3 / 0.67 h / Ambient temperature 5: 93 percent / aq.HF / acetonitrile / 24 h / Ambient temperature 6: 70 percent / DMAP / 0.33 h / 40 °C 7: 70 percent / Amberlyst A-21 / diethyl ether / 2 h / Ambient temperature 8: 55 percent / n-Bu3SnH, AIBN / toluene / 0.5 h / Heating 9: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 10: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 11: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 12: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 13: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 14: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme

1: 73 percent / sodium methoxide / methanol / 2 h / Ambient temperature 2: 85 percent / methanesulfonyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 3: 90 percent / NaBH4 / propan-2-ol; CHCl3 / 0.67 h / Ambient temperature 4: 93 percent / aq.HF / acetonitrile / 24 h / Ambient temperature 5: 70 percent / DMAP / 0.33 h / 40 °C 6: 70 percent / Amberlyst A-21 / diethyl ether / 2 h / Ambient temperature 7: 55 percent / n-Bu3SnH, AIBN / toluene / 0.5 h / Heating 8: 0.034 g / sodium borohydride / propan-2-ol; tetrahydrofuran / -78 deg C to rt, overnight 9: 80 percent / n-tetrabutylammonium iodide, NaH / tetrahydrofuran / 18 h / Ambient temperature 10: 85 percent / 48percent aq. HF / acetonitrile / 1.5 h / Ambient temperature 11: 1.) oxalyl chloride, DMSO 2.) triethylamine / 1.) CH2Cl2, -60 deg C, 15 min 2.) -60 deg C, 15 min 12: 78 percent / BF3.Et2O, bis(trimethylsilyl)peroxide / CH2Cl2 / 1.5 h / Ambient temperature; 2 13: 42 percent / boron trichloride / CH2Cl2; hexane / 4 h / -78 °C View Scheme