Hydrochloric Acid → 3-(3-Cyano-phenyl)-2-pyrrolidin-2-ylidene-propionic acid methyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a flask containing a 60% dispersion of NaH (0.91 g, 22.7 mmol), and toluene (60 mL), under nitrogen, is added Pyrrolidin-2-ylidene-acetic acid methyl ester (3.2 g, 22.7 mmol) and the mixture is refluxed for 1 h. The reaction mixture was cooled to 0° C. and a solution of m-cyanobenzylbromide (4.45 g, 22.7 mmol) in toluene (60 mL) is added dropwise. The reaction is allowed to warm to RT and then heated at 60° C. overnight. The mixture is cooled to RT and with vigorous stirring 1 N HCl is added to obtain a pH of 6. The toluene was decanted and dried over Na2SO4 and concentrated. Purification by flash chromatography (9:9:1 of CH2Cl2:hexanes:EtOAc) gave the title compound as a wet solid (3.2 g, 12.5 mmol). 1H NMR (CDCl3, 300 MHz) 8.32(br. s, 1H), 7.48-7.25(m, 4H), 3.63(s, 3H), 3.62-3.55(m, 2H), 3.53(s, 2H), 2.66-2.48(m, 2H), 2.10-1.90(m, 2H).

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