1.1: 61 percent / n-BuLi / tetrahydrofuran; hexane / 2 h / -78 - 20 °C 2.1: 83 percent / NaBH4 / ethanol / 20 °C 3.1: 90 percent / acetic acid / 2 h / 80 °C 4.1: 99 percent / H2 / 10percent Pd/C / ethyl acetate / 6 h / 2482.38 Torr 5.1: 82 percent / LiAlH4 / diethyl ether / 24 h / Heating 6.1: 100 percent / DMAP / pyridine / 16 h / 20 °C 7.1: 66 percent / PPL / dimethylsulfoxide; aq. phosphate buffer / 2.5 h / 20 °C / pH 7.8 8.1: 100 percent / imidazole / dimethylformamide / 7 h / 20 °C 9.1: 100 percent / K2CO3 / methanol / 1.5 h / 20 °C 10.1: 100 percent / oxalyl chloride; DMSO; Et3N / CH2Cl2 / -78 - -40 °C 11.1: 90 percent / NaOMe / methanol / 20 °C 12.1: 93 percent / i-Pr2NEt / CH2Cl2 / 0 - 20 °C 13.1: 95 percent / 2-methyl-2-butene; NaClO2; NaH2PO4 / 2-methyl-propan-2-ol; H2O / 20 °C 14.1: CDI / tetrahydrofuran / 3 h / 20 °C 14.2: 20 percent / KHMDS / tetrahydrofuran; toluene / 7 h / 0 - 20 °C 15.1: CDI / tetrahydrofuran / 3 h / 20 °C 15.2: 64 percent / n-BuLi / tetrahydrofuran; hexane / 4.5 h / -78 °C 16.1: 85 percent / CuCN / tetrahydrofuran / 3.5 h / 10 °C 17.1: TBAF / tetrahydrofuran / 5 h / 40 - 50 °C 17.2: 62 percent / benzene; CHCl3 / Heating 18.1: 65 percent / MgBr2*OEt2 / benzene; diethyl ether / 11 h / 0 - 20 °C View Scheme

1: nBuLi / -78 °C 2: TosOH / benzene / Heating 3: borane*Me2S / tetrahydrofuran / Heating View Scheme

1.1: 61 percent / n-BuLi / tetrahydrofuran; hexane / 2 h / -78 - 20 °C 2.1: 83 percent / NaBH4 / ethanol / 20 °C 3.1: 90 percent / acetic acid / 2 h / 80 °C 4.1: 99 percent / H2 / 10percent Pd/C / ethyl acetate / 6 h / 2482.38 Torr 5.1: 82 percent / LiAlH4 / diethyl ether / 24 h / Heating 6.1: 100 percent / DMAP / pyridine / 16 h / 20 °C 7.1: 66 percent / PPL / dimethylsulfoxide; aq. phosphate buffer / 2.5 h / 20 °C / pH 7.8 8.1: 100 percent / imidazole / dimethylformamide / 7 h / 20 °C 9.1: 100 percent / K2CO3 / methanol / 1.5 h / 20 °C 10.1: 100 percent / oxalyl chloride; DMSO; Et3N / CH2Cl2 / -78 - -40 °C 11.1: 90 percent / NaOMe / methanol / 20 °C 12.1: 93 percent / i-Pr2NEt / CH2Cl2 / 0 - 20 °C 13.1: 95 percent / 2-methyl-2-butene; NaClO2; NaH2PO4 / 2-methyl-propan-2-ol; H2O / 20 °C 14.1: CDI / tetrahydrofuran / 3 h / 20 °C 14.2: 20 percent / KHMDS / tetrahydrofuran; toluene / 7 h / 0 - 20 °C 15.1: CDI / tetrahydrofuran / 3 h / 20 °C 15.2: 64 percent / n-BuLi / tetrahydrofuran; hexane / 4.5 h / -78 °C 16.1: 85 percent / CuCN / tetrahydrofuran / 3.5 h / 10 °C 17.1: TBAF / tetrahydrofuran / 5 h / 40 - 50 °C 17.2: 62 percent / benzene; CHCl3 / Heating 18.1: 47 percent / LDA; Py*HCl / tetrahydrofuran / -78 - 20 °C 19.1: 81 percent / MgBr2*Et2O; EtSH / diethyl ether; benzene / 11 h / 0 - 20 °C View Scheme

toluene-4-sulfonic acid in methanol; benzene T=25°C; 1 h;

1: Br2, acetic acid 2: 100 percent / p-toluenesulfonic acid / methanol; benzene / 1 h / 25 °C View Scheme

dowex; bromine 1.) HOAc, 2.) MeOH; Multistep reaction;