ascorbic acid powder in ethanol T=78°C; 30 h;

1: With sodium dithionite in n-heptane; water T=25°C; pH=4 - 6; 2 h; Nitrogen atmosphere; 2: in ethanol; water T=2 - 50°C; Nitrogen atmosphere; Conversion of starting material;

sodium dithionite in n-heptane; water T=25°C; pH=4 - 6; 2 h; Nitrogen atmosphere; Conversion of starting material;

1: trimethylaluminum; (5E,9E,13E,17E,21E,25E)-6,10,14,18,22,26,30-Heptamethyl-hentriaconta-5,9,13,17,21,25,29-heptaen-1-yne With zirconocene dichloride in hexane; 1,2-dichloro-ethane carboalumination; 2: 2-chloromethyl-5,6-dimethoxy-3-methyl-[1,4]benzoquinone With NiCl2((PPh3)P)2; n-butyllithium in tetrahydrofuran; hexane Condensation;

1.1: 94 percent / NaBH4 / tetrahydrofuran / 0.5 h / -20 °C 2.1: POCl3 3.1: dimethylformamide / 20 °C 4.1: TsOH / methanol / 12 h / 20 °C 5.1: 65 percent / n-BuLi 6.1: 100 percent / LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran / 3 h / 0 °C 7.1: N-chlorosuccinimide; Me2S / CH2Cl2 / 2.5 h / 0 °C 8.1: 79 percent / n-BuLi 9.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 10.1: TBAF / tetrahydrofuran 11.1: Cp2ZrCl2 / 1,2-dichloro-ethane; hexane 11.2: 89 percent / NiCl2(PPh3)2; n-BuLi / tetrahydrofuran; hexane View Scheme

1.1: CuCl2; NaCl; conc. aq. HCl / benzene / 5 h / 50 °C 2.1: 94 percent / NaBH4 / tetrahydrofuran / 0.5 h / -20 °C 3.1: POCl3 4.1: dimethylformamide / 20 °C 5.1: TsOH / methanol / 12 h / 20 °C 6.1: 65 percent / n-BuLi 7.1: 100 percent / LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran / 3 h / 0 °C 8.1: N-chlorosuccinimide; Me2S / CH2Cl2 / 2.5 h / 0 °C 9.1: 79 percent / n-BuLi 10.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 11.1: TBAF / tetrahydrofuran 12.1: Cp2ZrCl2 / 1,2-dichloro-ethane; hexane 12.2: 89 percent / NiCl2(PPh3)2; n-BuLi / tetrahydrofuran; hexane View Scheme

1.1: POCl3 2.1: dimethylformamide / 20 °C 3.1: TsOH / methanol / 12 h / 20 °C 4.1: 65 percent / n-BuLi 5.1: 100 percent / LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran / 3 h / 0 °C 6.1: N-chlorosuccinimide; Me2S / CH2Cl2 / 2.5 h / 0 °C 7.1: 79 percent / n-BuLi 8.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 9.1: TBAF / tetrahydrofuran 10.1: Cp2ZrCl2 / 1,2-dichloro-ethane; hexane 10.2: 89 percent / NiCl2(PPh3)2; n-BuLi / tetrahydrofuran; hexane View Scheme

2.1: 88 percent / DCC; DMSO; 85 percent H3PO4 / benzene / 135 h 3.1: 96 percent / NaBH4 / tetrahydrofuran / 1 h / -20 °C 4.1: 98 percent / N-chlorosiccinimide; Me2S / CH2Cl2 / 2.5 h / 0 °C 5.1: 65 percent / n-BuLi 6.1: 100 percent / LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran / 3 h / 0 °C 7.1: N-chlorosuccinimide; Me2S / CH2Cl2 / 2.5 h / 0 °C 8.1: 79 percent / n-BuLi 9.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 10.1: TBAF / tetrahydrofuran 11.1: Cp2ZrCl2 / 1,2-dichloro-ethane; hexane 11.2: 89 percent / NiCl2(PPh3)2; n-BuLi / tetrahydrofuran; hexane View Scheme

1.1: 81 percent / N-chlorosuccinimide; Me2S / CH2Cl2 / 1.5 h / 0 °C 2.1: dimethylformamide 3.1: 79 percent / n-BuLi 4.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 5.1: TBAF / tetrahydrofuran 6.1: Cp2ZrCl2 / 1,2-dichloro-ethane; hexane 6.2: 89 percent / NiCl2(PPh3)2; n-BuLi / tetrahydrofuran; hexane View Scheme

1.1: POCl3 2.1: n-BuLi 2.2: -78 °C 3.1: TsOH / methanol 4.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 5.1: 81 percent / N-chlorosuccinimide; Me2S / CH2Cl2 / 1.5 h / 0 °C 6.1: dimethylformamide 7.1: 79 percent / n-BuLi 8.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 9.1: TBAF / tetrahydrofuran 10.1: Cp2ZrCl2 / 1,2-dichloro-ethane; hexane 10.2: 89 percent / NiCl2(PPh3)2; n-BuLi / tetrahydrofuran; hexane View Scheme