1: 1-methyl-pyrrolidin-2-one With sodium hydride; oxalic acid diethyl ester in diethyl ether T=35 - 40°C; Metallation; Acylation; 72 h; 2: formaldehyd in xylene T=100°C; Condensation; 1.5 h; Further stages.;

copper(l) iodide; dicyclohexyl-carbodiimide in toluene 1.16667 h; Heating;

1: 45 percent / NaH / toluene / 8 h / Heating 2: 80 percent / NaBH4; CaCl2 / methanol / 14 h / 20 °C 3: 52 percent / N,N-dicyclohexylcarbodiimide; CuI / toluene / 1.17 h / Heating View Scheme

1: 80 percent / NaBH4; CaCl2 / methanol / 14 h / 20 °C 2: 52 percent / N,N-dicyclohexylcarbodiimide; CuI / toluene / 1.17 h / Heating View Scheme