1: O-benzyl-hydroxylamine hydrochloride; formyl formic acid 2: triethyl borane With oxygen; chiral quaternary ammonium hypophosphite QP in hexane; dichloromethane; water T=20°C; 4 h;

4-(N,N-dimethlyamino)pyridine; dicyclohexyl-carbodiimide; trifluoroacetic acid 1.) CH2Cl2, 20 deg C, 12 h, 2.) toluene, hexane, 20 deg C, 1 h, 3.) CHCl3, 20 deg C, 30 min; Yield givenMultistep reaction;

1: 2-(benzyloxyimino)ethanoic acid With 4-(N,N-dimethlyamino)pyridine; dicyclohexyl-carbodiimide; Wang resin in dichloromethane T=20°C; 12 h; 2: diethylzinc in hexane; dichloromethane T=-78°C; 3: With trifluoroacetic acid in chloroform T=20°C; 0.5 h;

1: 2-(benzyloxyimino)ethanoic acid With pyridine; tetnaGel OH resin; 2,6-dichloro-1-benzenecarbonyl chloride in N,N-dimethyl-formamide T=20°C; 1 h; 2: triethyl borane; 1-trans-IODO-4-CYCLOPENTYL in methanol; water T=70°C; 1 h; 3: With trifluoroacetic acid in chloroform T=20°C; 0.5 h;

1: 71 percent / AcONa / methanol / 12 h / 20 °C 2: 99 percent Spectr. / hexane; H2O / 0.17 h / 20 °C View Scheme

in ethanol