1: 2-mercapto benzoic acid With sodium hydroxide in methanol T=25°C; 0.5 h; 2: 1-bromomethyl-4-methoxy-benzene in acetone 4 h; Reflux; 3: With hydrogenchloride in methanol; water

potassium carbonate in N,N-dimethyl-formamide 10 h; Heating;

1.1: (benzotriazo-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate; N-ethyl-N,N-diisopropylamine / N,N-dimethyl-formamide / 20 °C 2.1: 3-chloro-benzenecarboperoxoic acid / chloroform / 0.83 h / 0 °C 3.1: n-butyllithium / tetrahydrofuran; N,N,N',N',N'',N''-hexamethylphosphoric triamide; hexane / 0.17 h / -70 °C / Inert atmosphere 3.2: -78 °C / Inert atmosphere 4.1: 2,4,6-trimethyl-pyridine; oxalyl dichloride / dichloromethane / -50 °C / Inert atmosphere 5.1: sodium tetrahydroborate View Scheme

1.1: BOP; DIPEA / dimethylformamide 2.1: MCPBA / CHCl3 3.1: HMPA; n-BuLi / tetrahydrofuran / 0.17 h / -78 °C 3.2: 85 percent / tetrahydrofuran / -78 °C 4.1: CDCl3 / 31.85 °C View Scheme

1.1: BOP; DIPEA / dimethylformamide 2.1: MCPBA / CHCl3 3.1: HMPA; n-BuLi / tetrahydrofuran / 0.17 h / -78 °C 3.2: 90 percent / tetrahydrofuran / -78 °C 4.1: CDCl3 / 31.85 °C View Scheme

1.1: (benzotriazo-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate; N-ethyl-N,N-diisopropylamine / N,N-dimethyl-formamide / 20 °C 2.1: 3-chloro-benzenecarboperoxoic acid / chloroform / 0.83 h / 0 °C 3.1: n-butyllithium / tetrahydrofuran; N,N,N',N',N'',N''-hexamethylphosphoric triamide; hexane / 0.17 h / -70 °C / Inert atmosphere 3.2: -78 °C / Inert atmosphere 4.1: 2,4,6-trimethyl-pyridine; oxalyl dichloride / dichloromethane / -50 °C / Inert atmosphere View Scheme

1.1: (benzotriazo-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate; N-ethyl-N,N-diisopropylamine / N,N-dimethyl-formamide / 20 °C 2.1: 3-chloro-benzenecarboperoxoic acid / chloroform / 0.83 h / 0 °C 3.1: n-butyllithium / tetrahydrofuran; N,N,N',N',N'',N''-hexamethylphosphoric triamide; hexane / 0.17 h / -70 °C / Inert atmosphere 3.2: -78 °C / Inert atmosphere 4.1: 2,4,6-trimethyl-pyridine; trifluoromethylsulfonic anhydride / acetonitrile / 0 °C / Inert atmosphere View Scheme

1.1: (benzotriazo-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate; N-ethyl-N,N-diisopropylamine / N,N-dimethyl-formamide / 20 °C 2.1: 3-chloro-benzenecarboperoxoic acid / chloroform / 0.83 h / 0 °C 3.1: n-butyllithium / tetrahydrofuran; N,N,N',N',N'',N''-hexamethylphosphoric triamide; hexane / 0.17 h / -70 °C / Inert atmosphere 3.2: -78 °C / Inert atmosphere 4.1: 2,4,6-trimethyl-pyridine; trifluoroacetic anhydride / dichloromethane / 0 - 20 °C / Inert atmosphere View Scheme