1.1: 4-toluenesulfonic acid; H2 / Pd/C / dimethylformamide / 48 h 2.1: N-methylmorpholine / dimethylformamide / 24 h / 20 °C 2.2: 54 percent / TFA, 50 percent / CHCl3 View Scheme

hydrogen; toluene-4-sulfonic acid; palladium on activated charcoal in N,N-dimethyl-formamide Hydrogenation; deprotection; 48 h; Title compound not separated from byproducts;