1.1: tert.-butyl lithium / hexane; diethyl ether / 4 h / -78 °C / Inert atmosphere 1.2: 0.92 h / -78 - -50 °C / Inert atmosphere 2.1: diisobutylaluminium hydride / toluene / 3 h / -78 °C 2.2: -50 °C 3.1: 4-(N,N-dimethlyamino)pyridine; diisopropyl-carbodiimide / tetrahydrofuran / 24 h / 20 - 40 °C 4.1: RuCl2(tricyclohexylphosphine)2(benzylidene) / dichloromethane / 18 h / 20 - 40 °C / Inert atmosphere 5.1: tetrabutyl ammonium fluoride; ammonium hydrogen difluoride / tetrahydrofuran / 24 h / 20 - 40 °C 6.1: sodium hydride / isopropyl alcohol; mineral oil / 18 h / 20 - 35 °C 6.2: 18 h / 20 °C View Scheme

1.1: n-butyllithium / hexane; tert-butyl methyl ether / 2 h / -78 °C / Inert atmosphere 1.2: 0.75 h / -78 °C / Inert atmosphere 2.1: diisobutylaluminium hydride / toluene / 3 h / -78 °C 2.2: -50 °C 3.1: 4-(N,N-dimethlyamino)pyridine; diisopropyl-carbodiimide / tetrahydrofuran / 24 h / 20 - 40 °C / Inert atmosphere 4.1: RuCl2(tricyclohexylphosphine)2(benzylidene) / dichloromethane / 18 h / 20 - 40 °C / Inert atmosphere 5.1: tetrabutyl ammonium fluoride; ammonium hydrogen difluoride / tetrahydrofuran / 24 h / 20 - 40 °C 6.1: trimethylaluminum / tetrahydrofuran / 18 h / 20 - 40 °C View Scheme