1: With phosphorus pentachloride; iodine in chloroform T=0°C; 0.5 h; 2: With bromine in chloroform T=0 - 20°C; 4 h; Refluxed;

(+)-Norephedrine in dichloromethane

PPA Yield given;

1: NH2OH*HCl / H2O 2: polyphosphoric acid View Scheme

1: Br2 / methanol 2: NH2OH*HCl / H2O 3: polyphosphoric acid View Scheme

in N,N-dimethyl-formamide T=60°C; 16 h;

1: sodium azide; sodium iodide / N,N-dimethyl-formamide / 24 h / 20 °C 2: triphenylphosphine / tetrahydrofuran; water / 20 h / 20 - 60 °C / |Inert atmosphere View Scheme

1: 93 percent / Na2CO3, propylene glycol / 3.5 h / 130 °C 2: 88 percent / odorless mineral spirits / 16 h / 140 °C 3: 1.) tetrabutylammonium hydrogen sulfate, 50percent NaOH, 3.) H2 / 3.) 5percent Pd/C / 1.) toluene, 35 deg C, 1 h; 20 deg C, 16 h, 2.) toluene, 20 deg C, 1 h, 3.) EtOH, 60 deg C, 55 psi, 16 h View Scheme

1: sodium azide; sodium iodide / N,N-dimethyl-formamide / 24 h / 20 °C 2: triphenylphosphine / tetrahydrofuran; water / 20 h / 20 - 60 °C / |Inert atmosphere 3: (R)-(+)-2-pyrrolidone-5-carboxylic acid; 2-hydroxy-5-nitro-benzaldehyde / water; isopropyl alcohol / 48 h / 70 °C / |Inert atmosphere 4: water; acetonitrile / 0.67 h / 73 °C View Scheme

1: 83 percent / dimethylformamide / 16 h / 60 °C 2: 93 percent / kalium-(tert-butylat) / dimethylformamide / 1 h / 0 - 5 °C 3: 85 percent / 2-aminoethanol / 0.08 h / 80 °C View Scheme