in toluene 8 h; Reflux;

hydrogen in N,N-dimethyl-formamide T=60°C; 0.5 h;

1: With sodium hydroxide in ethanol T=80°C; 16 h; Inert atmosphere; 2: With sodium t-butanolate in ethanol T=80°C; 16 h; Inert atmosphere;

1.1: N-ethyl-N,N-diisopropylamine; n-butyllithium / tetrahydrofuran; hexane / 0.33 h / -78 °C / |Inert atmosphere 1.2: -78 - 20 °C / |Inert atmosphere 2.1: n-butyllithium / tetrahydrofuran; hexane / 1 h / |Inert atmosphere; |Cooling 2.2: 1 h / |Inert atmosphere; |Cooling View Scheme