反应详情

Under an argon atmosphere, 1.81 g (5.5 mmol) of N-benzyl-2-bromo-pyridinium bromide [for preparation see J. Heterocyclic Chem. 28,1083 (1991)] are added to 605.5 mg (5.0 mmol) of 2-amino-3-cyano-4-methyl-pyrrole [for preparation see Synthesis (1976), 51] in 40 ml of methylene chloride and 639 μl (5.5 mmol) of lutidine. After 5.5 hours' stirring at RT, the reaction mixture is concentrated by evaporation to approximately half its original volume. Filtering the suspension and washing with methylene chloride/ethyl acetate (1:1) and ethyl acetate/hexane (1:1) yield the title compound; 1H-NMR (300 MHz, DMSO-d6): 10.83 (s, 1H), 9.10 (d, J=7, 1H), 8.49 (t, J=7, 1H), 7.96 (m, 2H), 7.30 (m, 3H), 6.95 (m, 2H), 6.57 and 5.80 (2s, each 2H), 1.76 (s, 3H); FAB-MS: (M+H)+ =289.

1. concentrationthe reaction mixture is concentrated by evaporation to approximately half its original volume
2. filtrationFiltering the suspension
3. washwashing with methylene chloride/ethyl acetate (1:1) and ethyl acetate/hexane (1:1)