1: With lithium diisopropyl amide in diethyl ether; hexane T=-10°C; 2 h; 2: With boric acid trimethyl ester in diethyl ether; hexane T=-10 - 20°C; 3: With hydrogenchloride in diethyl ether; hexane

1.1: K2CO3; KI 2.1: polyphosphoric acid / chlorobenzene 3.1: LDA / hexane; diethyl ether / 2 h / -10 °C 3.2: trimethyl borate / hexane; diethyl ether / -10 - 20 °C 3.3: 78 percent / aq. HCl / diethyl ether; hexane View Scheme

1.1: polyphosphoric acid / chlorobenzene 2.1: LDA / hexane; diethyl ether / 2 h / -10 °C 2.2: trimethyl borate / hexane; diethyl ether / -10 - 20 °C 2.3: 78 percent / aq. HCl / diethyl ether; hexane View Scheme