1: With 4-methyl-morpholine in ethylene glycol dimethyl ether T=-15°C; 1 h; 2: With sodium tetrahydroborate in ethylene glycol dimethyl ether; water T=-15°C; Further stages.;

sodium tetrahydroborate in methanol; diethyl ether T=20°C; 1 h;

1: 98 percent / Et2NH / CH2Cl2 / 3 h 2: 90 percent / Et3N / dimethylformamide / overnight 3: 98 percent / CF3COOH / CH2Cl2 / 0.67 h / Ambient temperature View Scheme