1: 4-methoxy-benzaldehyde; [14C]-4-Aminobutyric acid With sodium hydroxide; hydrogen; palladium 10 on activated carbon in ethanol; water T=20°C; 168 h; 2: di-tert-butyl dicarbonate in ethanol; water T=20°C; 3 h;

in tetrahydrofuran T=20°C; 3 h;

1: palladium 10 on activated carbon; hydrogen / ethanol; water / 168 h / 20 °C 2: tetrahydrofuran / 3 h / 20 °C View Scheme