Peracetic Acid → 4-Chloro-2-pyridinecarbonitrile

Beteiligte Stoffe

Reaktionsschritte

4-Chloro-2-pyridinecarboxamide (93.9 g, 0.6 moles) and TEA (125 mL, 0.9 moles) in EtOAc (500 mL) was cooled to 0.2° C. via an external chiller unit. TFAA (92 mL, 0.66 moles) was added via addition funnel over 40 min. The internal temperature rose to 10° C. during the addition. The temperature at the completion of the addition was 0.0° C. After addition, the chiller was turned off. After an additional 30 min, HPLC analysis showed 4.3% (LCAP) of the starting material. An additional 8.3 mL (0.06 moles) of TFAA was added. After stirring the reaction mixture for an additional 20 min, HPLC analysis indicated complete conversion. 10% Aqueous K2CO3 (w/v, 500 mL) was added. The internal temperature rose from 13.7 to 22.0° C. The mixture was transferred to a separatory funnel after stirring for 20 min. The layers were separated and the aqueous layer extracted with EtOAc (150 mL). The combined organic layers were washed with 10% aqueous citric acid (w/v, 300 mL), dried (Na2SO4), filtered, and concentrated. The crude product was dried in a vacuum oven at 50° C. for 16 h to afford 72.85 g (87%) of the title compound: 1H NMR (400 MHz, CDCl3) δ 8.6 (m, 1 H), 7.7 (m, 1 H), 7.5 (m, 1H); 13C NMR (100 MHz, CDCl3) δ 151.8, 145.3, 134.9, 128.7, 127.4, 116.1; HPLC>99% (LCAP).

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