反应详情

To an ice cold solution of ethylcyanoacetate (10.9 mL, 102.4 mmol) in anhydrous THF (170 mL) under nitrogen, was added potassium tert-butoxide (12.7 g, 107.5 mmol). The formed white suspension was stirred for 15 min, then treated with 2,3-dichloronitrobenzene (9.83 g, 51.2 mmol). The suspension was heated at reflux for 48 hours. The resulting reddish brown solution was poured in to water, and the aqueous-mixture was acidified to pH 2 with conc. HCl. The mixture was extracted with ether (3×150 mL) and then the combined organic phase was dried (using Na2SO4) and concentrated to give a dark oil, Flash chromatography using 10:1 hexane:ethyl acetate in a column packed with silica gel, 10 times the weight of the dark oil, provided a viscous yellow liquid 4, which was used without further purification for the next step. TLC Rf 0.23 (hexane-ethyl acetate 3:1). 1H NMR δ 1.33-1.38 (t, 3H, CH3); 4.29-4.35 (q, 2H, CH2); 7.59-8.14 (m, 3H, phenyl).

1. temperatureThe suspension was heated
2. temperatureat reflux for 48 hours
3. extractionThe mixture was extracted with ether (3×150 mL)
4. dry with materialthe combined organic phase was dried (using Na2SO4)
5. concentrationconcentrated
6. customto give a dark oil, Flash chromatography