Potassium Carbonate → Indoline-2-carboxylic acid, (S)-

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A flask was charged successively with 4.89 g (20.0 mmol) (S)-2-bromophenylalanine, 2.93 g (21.2 mmol) K2CO3, 0.2 mg CuCl (2.9 mmol) and 39.7 g H2O. The reactor was flushed with argon and then kept under a slow stream of argon. The reaction mixture was stirred and heated until 95° C. and kept at this temperature. Samples were taken regularly and analyzed by HPLC. After 4 h hour full conversion of (S)-2-bromophenylalanine was found. The reaction mixture was cooled to 25° C. Then the reaction mixture was acidified with 4.47 g 5M aqueous HCl until pH=4.4. The precipitated (S)-2,3-dihydro-1H-indole-2-carboxylic acid was isolated by filtration and washed with 2×10 mL H2O. Found after drying 2.24 g (13.7 mmol) (S)-2,3-dihydro-1H-indole-2-carboxylic acid. Yield 69%, ee>99%.

Herkunft & Nachweise