1: 97 percent / tetrahydrofuran / 3 h / -78 °C 2: Et3N / tetrahydrofuran / 0 - 20 °C 3: 0.70 g / LiEt3BH / tetrahydrofuran / 18 h / 60 °C 4: 77 percent / [1,3-dimesitylimidazolidin-2-yl]Cl2(PCy3)Ru=CHPh / CH2Cl2 / 6 h / Heating View Scheme

1.1: n-BuLi / tetrahydrofuran / 0.5 h / 0 °C 1.2: tetrahydrofuran / 4 h / 20 °C 2.1: Bu4NF / tetrahydrofuran / 8 h / 26 °C View Scheme

sodium tetrahydroborate; water in methanol T=0°C;