1.1: Et3N / diethyl ether / -20 - 20 °C 2.1: 92 percent / n-BuLi / tetrahydrofuran; hexane / 2 h / -50 - 20 °C 3.1: n-BuLi / tetrahydrofuran; hexane / 0.08 h / -50 °C 3.2: 91 percent / H2O / tetrahydrofuran; hexane / -50 °C 4.1: 85 percent / aq. H2SO4 / benzene / 4 h / Heating View Scheme

1.1: Et3N / diethyl ether / -20 - 20 °C 2.1: 92 percent / n-BuLi / tetrahydrofuran; hexane / 2 h / -50 - 20 °C 3.1: n-BuLi / tetrahydrofuran; hexane / 0.17 h / -50 °C 3.2: 86 percent / tetrahydrofuran; hexane / 1 h / -50 - 20 °C 4.1: 70 percent / aq. H2SO4 / benzene / 4 h / Heating View Scheme

1.1: Et3N / diethyl ether / -20 - 20 °C 2.1: 92 percent / n-BuLi / tetrahydrofuran; hexane / 2 h / -50 - 20 °C 3.1: n-BuLi / tetrahydrofuran; hexane / 0.17 h / -50 °C 3.2: 94 percent / tetrahydrofuran; hexane / 1 h / -50 - 20 °C 4.1: 70 percent / aq. H2SO4 / benzene / 4 h / Heating View Scheme

1.1: Et3N / diethyl ether / -20 - 20 °C 2.1: 92 percent / n-BuLi / tetrahydrofuran; hexane / 2 h / -50 - 20 °C 3.1: n-BuLi / tetrahydrofuran; hexane / 0.17 h / -50 °C 3.2: 74 percent / tetrahydrofuran; hexane / 1 h / -50 - 20 °C 4.1: 61 percent / aq. H2SO4 / benzene / 4 h / Heating View Scheme

1.1: Et3N / diethyl ether / -20 - 20 °C 2.1: 92 percent / n-BuLi / tetrahydrofuran; hexane / 2 h / -50 - 20 °C 3.1: n-BuLi / tetrahydrofuran; hexane / 0.17 h / -50 °C 3.2: 75 percent / tetrahydrofuran; hexane / 1 h / -50 - 20 °C 4.1: 67 percent / aq. H2SO4 / benzene / 4 h / Heating View Scheme

1.1: Et3N / diethyl ether / -20 - 20 °C 2.1: 92 percent / n-BuLi / tetrahydrofuran; hexane / 2 h / -50 - 20 °C 3.1: n-BuLi / tetrahydrofuran; hexane / 0.17 h / -50 °C 3.2: 98 percent / tetrahydrofuran; hexane / 1 h / -50 - 20 °C 4.1: 84 percent / aq. H2SO4 / benzene / 4 h / Heating View Scheme