potassium hydroxide in ethanol; water 2 h; Heating;

n-butyllithium in diethyl ether; hexane T=-75°C; 0.25 h;

1: 89 percent / butyllithium / hexane; tetrahydrofuran / -75 °C 2: 92 percent / sec-butyllithium; bromine / cyclohexane; tetrahydrofuran / 0.75 h 3: 82 percent / diisopropylamine; butyllithium / hexane; tetrahydrofuran / -75 °C 4: diisopropylamine; butyllithium / hexane; tetrahydrofuran / 2 h / -75 °C 5: 59 percent / butyllithium / diethyl ether; hexane / 0.25 h / -100 °C 6: 93 percent / butyllithium / hexane; diethyl ether / 0.25 h / -75 °C View Scheme

1: 89 percent / butyllithium / hexane; tetrahydrofuran / -75 °C 2: 92 percent / sec-butyllithium; bromine / cyclohexane; tetrahydrofuran / 0.75 h 3: 82 percent / diisopropylamine; butyllithium / hexane; tetrahydrofuran / -75 °C 4: diisopropylamine; butyllithium / hexane; tetrahydrofuran / 2 h / -75 °C 5: 59 percent / butyllithium / diethyl ether; hexane / 0.25 h / -100 °C 6: 93 percent / butyllithium / hexane; diethyl ether / 0.25 h / -75 °C View Scheme

1: 92 percent / sec-butyllithium; bromine / cyclohexane; tetrahydrofuran / 0.75 h 2: 82 percent / diisopropylamine; butyllithium / hexane; tetrahydrofuran / -75 °C 3: diisopropylamine; butyllithium / hexane; tetrahydrofuran / 2 h / -75 °C 4: 59 percent / butyllithium / diethyl ether; hexane / 0.25 h / -100 °C 5: 93 percent / butyllithium / hexane; diethyl ether / 0.25 h / -75 °C View Scheme

1: 82 percent / diisopropylamine; butyllithium / hexane; tetrahydrofuran / -75 °C 2: diisopropylamine; butyllithium / hexane; tetrahydrofuran / 2 h / -75 °C 3: 59 percent / butyllithium / diethyl ether; hexane / 0.25 h / -100 °C 4: 93 percent / butyllithium / hexane; diethyl ether / 0.25 h / -75 °C View Scheme

1: 59 percent / butyllithium / diethyl ether; hexane / 0.25 h / -100 °C 2: 93 percent / butyllithium / hexane; diethyl ether / 0.25 h / -75 °C View Scheme

1: diisopropylamine; butyllithium / hexane; tetrahydrofuran / 2 h / -75 °C 2: 59 percent / butyllithium / diethyl ether; hexane / 0.25 h / -100 °C 3: 93 percent / butyllithium / hexane; diethyl ether / 0.25 h / -75 °C View Scheme