in tetrahydrofuran T=20°C; 2 h;

1: furfural diethyl acetal With n-butyllithium in ethylene glycol dimethyl ether; hexane T=-50°C; 5 h; Inert atmosphere; 2: 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane in ethylene glycol dimethyl ether; hexane T=-40 - 20°C; 6.5 h; Inert atmosphere;

palladium 10 on activated carbon; N-ethyl-N,N-diisopropylamine in methanol 8 h; Reflux;

1.1: palladium 10 on activated carbon; N-ethyl-N,N-diisopropylamine / methanol / 8 h / |Reflux 2.1: N-ethyl-N,N-diisopropylamine; acetic acid / tetrahydrofuran / 1 h / 40 °C 2.2: 3 h / 20 °C View Scheme