dimethylsulfide; trifluorormethanesulfonic acid; trifluoroacetic acid in methoxybenzene T=0°C; Decarboxylation; detosylation; saponification;

1: 93 percent / HCl / ethyl acetate / 3 h / 20 °C 2: 92 percent / H2; formic acid / Pd/C / methanol / 24 h / 20 °C / 150.01 Torr View Scheme

1.1: HCl / ethyl acetate / 2 h / 20 °C 2.1: 1-hydroxybenzotriazole hydrate; N,N'-dicyclohexylcarbodiimide / tetrahydrofuran / 0.5 h / 0 °C 2.2: 91 percent / N-methylmorpholine / tetrahydrofuran / 8 h / 20 °C / pH 8.5 3.1: 93 percent / HCl / ethyl acetate / 2 h / 20 °C 4.1: 1-hydroxybenzotriazole hydrate; N,N'-dicyclohexylcarbodiimide / tetrahydrofuran / 0.5 h / 0 °C 4.2: 89 percent / N-methylmorpholine / tetrahydrofuran / 8 h / 20 °C / pH 8.5 5.1: 93 percent / HCl / ethyl acetate / 3 h / 20 °C 6.1: 92 percent / H2; formic acid / Pd/C / methanol / 24 h / 20 °C / 150.01 Torr View Scheme

1.1: 93 percent / HCl / ethyl acetate / 2 h / 20 °C 2.1: 1-hydroxybenzotriazole hydrate; N,N'-dicyclohexylcarbodiimide / tetrahydrofuran / 0.5 h / 0 °C 2.2: 89 percent / N-methylmorpholine / tetrahydrofuran / 8 h / 20 °C / pH 8.5 3.1: 93 percent / HCl / ethyl acetate / 3 h / 20 °C 4.1: 92 percent / H2; formic acid / Pd/C / methanol / 24 h / 20 °C / 150.01 Torr View Scheme

1: 63 percent / HF View Scheme

1: DCC / tetrahydrofuran / 0 °C 2: 83 percent / 4-methylmorpholine / tetrahydrofuran / 30 h / 20 °C 3: 85 percent / Me2S; CF3COOH; CF3SO3H / methoxybenzene / 0 °C View Scheme

1: 83 percent / 4-methylmorpholine / tetrahydrofuran / 30 h / 20 °C 2: 85 percent / Me2S; CF3COOH; CF3SO3H / methoxybenzene / 0 °C View Scheme

1: 63 percent / HF View Scheme

1: 63 percent / HF View Scheme

1: 63 percent / HF View Scheme