triethylamine; 1,1'-carbonyldiimidazole; magnesium chloride in acetonitrile T=50°C;

10 palladium on charcoal; hydrogen in ethyl acetate T=20°C; P=760.051 Torr;

1: propanedioic acid monoethyl ester With iso-propylmagnesium bromide in tetrahydrofuran T=0 - 40°C; 2: tert-butyloxycarbonylglycine imidazolide in tetrahydrofuran T=0 - 20°C; 3: With water; sodium hydrogencarbonate in tetrahydrofuran T=0°C;

1: triethylamine / tetrahydrofuran / 0.5 h / -30 - -20 °C 2: 1.) diisopropylamine, n-BuLi / 1.) THF, -70 deg C, 30 min, 2.) THF, -65 deg C, 20 min View Scheme

1: malonic acid ethyl ester monopotassium salt With triethylamine; magnesium chloride T=20°C; 4 h; 2: tert-butyloxycarbonylglycine imidazolide T=20°C; 16 h;

n-butyllithium; diisopropylamine 1.) THF, -70 deg C, 30 min, 2.) THF, -65 deg C, 20 min; Yield given. Multistep reaction;

(i) 1H,1'H-1,1'-sulfinyl-bis-imidazole, THF, (ii) /BRN= 4163159/, THF, (iii) aq. HCl; Multistep reaction;