反应详情

To a solution of 200 mg (1.04 mmol) of 5,6-dichloronicotinic acid in 5.0 mL of CH2Cl2 was added 273 μL (3.13 mmol) of oxalyl chloride and one drop of DMF. After stirring at rt overnight, the mixture was concentrated and dried azeotropically using toluene (3×5 mL). The residue was dissolved in 5.0 mL of dichloroethane and added to a solution of 242 mg (0.87 mmol) of N-HYDROXYAMIDINE 1 and 182 μL (1.30 mmol) of triethylamine in 5.0 mL of dichloroethane. After stirring at rt for 1 hr and at 120° C. overnight, the reaction mixture was cooled to rt and concentrated. Chromatography on a Biotage 40S cartridge using 1:19 v/v EtOAc/hexanes as the eluant gave 303 mg of the title compound: 1H NMR (500 MHz, CDCl3) δ 1.44 (s, 9H), 2.58 (t, J=7.8, 2H), 2.65 (s, 3H), 2.95 (t, J=7.7, 2H), 7.17-7.19 (m, 2H), 8.00 (d, J=8.5, 1H), 8.53 (d, J=2.0, 1H), 9.08 (d, J=2.0, 1H).

1. concentrationthe mixture was concentrated
2. dry with materialdried azeotropically using toluene (3×5 mL)
3. dissolutionThe residue was dissolved in 5.0 mL of dichloroethane
4. stirringAfter stirring at rt for 1 hr and at 120° C. overnight
5. temperaturethe reaction mixture was cooled to rt
6. concentrationconcentrated