1: 80 percent / DMSO; (COCl)2; Et3N / CH2Cl2 / 2 h / -78 - 20 °C 2: n-BuLi; diisopropylamine / hexane; tetrahydrofuran / 1 h / -10 °C 3: 49 percent / aq. HCl / 24 h / 20 °C 4: 56 percent / [Rh(binap)]BF4 / CH2Cl2 / 66 h / 20 °C View Scheme

1: 80 percent / DMSO; (COCl)2; Et3N / CH2Cl2 / 2 h / -78 - 20 °C 2: n-BuLi; diisopropylamine / hexane; tetrahydrofuran / 1 h / -10 °C 3: 49 percent / aq. HCl / 24 h / 20 °C 4: 56 percent / [Rh(binap)]BF4 / CH2Cl2 / 66 h / 20 °C View Scheme

hydrogen; palladium on activated charcoal in ethanol P=2068.65 Torr; 2 h;

copper(l) iodide; tetrakis(triphenylphosphine) palladium(0); diisopropylamine in tetrahydrofuran T=20°C;

1: phenylacetylene With n-butyllithium in tetrahydrofuran; hexane T=0°C; 1.5 h; Inert atmosphere; 2: 1-iodo-4-[(tetrahydropyran-2-yl)oxy]butane With N,N,N',N',N'',N''-hexamethylphosphoric triamide in tetrahydrofuran; hexane T=0 - 20°C; 12.5 h; Inert atmosphere; 3: With toluene-4-sulfonic acid in methanol; water T=20°C; 2 h; Inert atmosphere;

toluene-4-sulfonic acid in methanol T=60°C; 96 h;

1: 80 percent / DMSO; (COCl)2; Et3N / CH2Cl2 / 2 h / -78 - 20 °C 2: n-BuLi; diisopropylamine / hexane; tetrahydrofuran / 1 h / -10 °C 3: 49 percent / aq. HCl / 24 h / 20 °C 4: 41 percent / [Rh(binap)]BF4 / 1,2-dichloro-ethane / 19 h / 50 °C View Scheme

1: Et3N / CH2Cl2 / 1.5 h / 0 °C 2: NaN3 / dimethylformamide / 60 °C 3: 2.00 g / LiAlH4 / diethyl ether / 0 - 20 °C View Scheme