sodium carbonate in tetrahydrofuran; water T=20 - 50°C; 4 h;

in dichloromethane T=25°C; 48 h;

sodium hydroxide in 1-methyl-pyrrolidin-2-one; ethanol T=110°C; pH=9; 10 h;

1: 80 percent / 1-hydroxybenzotriazole; 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride / dimethylformamide; toluene / 18 h / 20 °C 2: hydrochloric acid / ethanol / 6 h / 20 °C 3: 5.44 g / NaOH / ethanol; 1-methyl-pyrrolidin-2-one / 10 h / 110 °C / pH 9 View Scheme

1: 80 percent / 1-hydroxybenzotriazole; 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride / dimethylformamide; toluene / 18 h / 20 °C 2: hydrochloric acid / ethanol / 6 h / 20 °C 3: 5.44 g / NaOH / ethanol; 1-methyl-pyrrolidin-2-one / 10 h / 110 °C / pH 9 View Scheme

1: hydrochloric acid / ethanol / 6 h / 20 °C 2: 5.44 g / NaOH / ethanol; 1-methyl-pyrrolidin-2-one / 10 h / 110 °C / pH 9 View Scheme

1: 86 percent / H2SO4, NaNO3 / 2 h / -5 °C 2: 85 percent / iron filings, CaCl2, H2O / ethanol / 16 h / Heating 3: 70 percent / Br2, AcOH / 16 h / Ambient temperature 4: 1.) conc HCl, NaNO2, 2.) 50 percent H3PO2 / 1.) from -10 deg C to 0 deg C, 2 h, 2.) RT, overnight 5: 93 percent / conc. HCl / 16 h / Heating 6: DIBAL-H / toluene / 0.67 h / Heating 8: HOBT, DEC / dimethylformamide / 24 h / 25 °C 9: TFA / CH2Cl2 / 24 h / 25 °C 10: 82 percent / CH2Cl2 / 48 h / 25 °C View Scheme

2: HOBT, DEC / dimethylformamide / 24 h / 25 °C 3: TFA / CH2Cl2 / 24 h / 25 °C 4: 82 percent / CH2Cl2 / 48 h / 25 °C View Scheme

1: DIBAL-H / toluene / 0.67 h / Heating 3: HOBT, DEC / dimethylformamide / 24 h / 25 °C 4: TFA / CH2Cl2 / 24 h / 25 °C 5: 82 percent / CH2Cl2 / 48 h / 25 °C View Scheme

1: 93 percent / conc. HCl / 16 h / Heating 2: DIBAL-H / toluene / 0.67 h / Heating 4: HOBT, DEC / dimethylformamide / 24 h / 25 °C 5: TFA / CH2Cl2 / 24 h / 25 °C 6: 82 percent / CH2Cl2 / 48 h / 25 °C View Scheme