Hydrochloric Acid → 2-(3,4-Dichloro-phenylamino)-propionic Acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 3,4-dichloroiodobenzene (1.50 g, 5.50 mmol), L-alanine (734 mg, 8.25 mmol), copper(I) iodide, 2-hydroxybenzaldehyde phenylhydrazone (233 mg, 1.10 mmol), tri-potassium phosphate (3.50 g, 16.5 mmol), and N,N-dimethylformamide (8 mL) was stirred at 80° C. for 40 h, then after cooling diluted with water and acidified to pH 3 by addition of 37% aq. HCl solution. The mixture was extracted with EtOAc, the organic phase was washed with brine, dried (MgSO4), filtered, and evaporated. Chromatography (SiO2; EtOAc) afforded the title compound (1.08 g, 67%) as a 71:29 mixture of the (S) and (R) stereoisomers (accordingly, when D-alanine was used instead of L-alanine as starting material, the title compound was obtained as a 29:71 mixture of the (S) and (R) stereoisomers). Brown solid, MS: 232.1 (M−H)−.

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