Diisopropylamine → 2-Pyridylmalononitrile

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To diisopropylamine (15.3 mL, 109 mmol) in toluene (500 mL), at 0-5° C., under nitrogen, was added drop wise over ˜½ hour 1.6M″ BuLi/THF (68.5 mL, 109 mmol). The reaction mixture was stirred for a further 15 minutes before the drop wise addition of 2-pyridylacetonitrile (5.55 mL, 49.6 mmol) over 1 hour. 2-Chlorobenzylthiocyanate (20.0 g, 109 mmol), described in the literature by Schlesinger J. Am. Chem. Soc. 1954, 76, 585, was then added in solution in toluene (100 mL) over a period of 1 hour. The reaction mixture was stirred for an additional 2 hours. Water was added and the layers were separated. The organic phase was extracted twice with 200 mL 2N NaOH. The combined aqueous phases were cooled down to 0° C and acidified to ˜pH 1. The precipitate obtained was filtered and dried to give the title compound as a pale tan solid (4.50 g, 63% yield). δH (DMSO-d6) 6.79 (1H, t), 7.09 (1H, d), 7.73 (1H, t), 7.79 (1H, dd), 12.95 (1H, br s).

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