The title compound 2-amino-3-ethoxycarbonyl-4-(4-chlorophenyl)-4H,5H-pyrano- [3,2-c]-benzopyran-5-one (C21H16ClNO5, Mr = 397.80) has been synthesized and characterized by X-ray crystallography. It crystallizes in tric...The title compound 2-amino-3-ethoxycarbonyl-4-(4-chlorophenyl)-4H,5H-pyrano- [3,2-c]-benzopyran-5-one (C21H16ClNO5, Mr = 397.80) has been synthesized and characterized by X-ray crystallography. It crystallizes in triclinic, space group P1 with a = 5.756(1), b = 10.099(1), c = 17.106(3) ? a = 80.49(1), b = 83.13(1), g = 80.07(1), V = 961.8(2) ?, Dc = 1.374 g/cm3, = 0.231 mm-1, Z = 2, F(000) = 412, the final R = 0.0369 and wR = 0.0947. In the molecule the pyran ring is of boat conformation. The intermolecular hydrogen bonds of NH…O(5)(x+2, y+1, z+1) and NH…Cl (x+1, y1, z) as well as intramolecular hydrogen bond NH…O(5) are found.展开更多
The conjugate hydrocyanation of chalcone derivatives using ethyl cyanoacetate as an organic cyanide source at room temperature under open air and transition metal-free conditions was described. The protocol has advant...The conjugate hydrocyanation of chalcone derivatives using ethyl cyanoacetate as an organic cyanide source at room temperature under open air and transition metal-free conditions was described. The protocol has advantages of using relatively cheap, less toxic, stable and easy-to-handle cyanating reagent, high yield, and mild reaction condi- tion.展开更多
Comparative experiments show that ultrasonic irradiation reduces the reaction times and improves the yields in the di-alkylation and cyclo-di-alkylation of ethyl cyanoacetate under solid-liquid phase transfer conditions.
An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temp...An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temperature.展开更多
The title compound ethyl 2-(2-amino-3-ethoxycarbonyl-4H-benzopyran-4-yl) cyanoacetate(C17H18N2O5, Mr=330.33) was obtained by the reaction of salicylaldehyde with ethyl cyanoacetate in DMF at room temperature catalyzed...The title compound ethyl 2-(2-amino-3-ethoxycarbonyl-4H-benzopyran-4-yl) cyanoacetate(C17H18N2O5, Mr=330.33) was obtained by the reaction of salicylaldehyde with ethyl cyanoacetate in DMF at room temperature catalyzed by KF-Al2O3. The crystal is monoclinic, space group P21/n, with unit cell constants a =9.277(3), b =8.521(2), c =21.320(2)? b =93.72(2)? Z =4, V =1681.8(7)?, Dc =1.305g/cm3, m (MoKa) =0.097mm-1, F(000) =696, R =0.0426, Rw =0.0970 for 3042 observed reflections(I>2s(I)). X-ray analysis reveals that interatomic distance for C(8)C(9) is 1.359(3)? which shows that it is C=C double bond. In addition, there are hydrogen bonds in the molecule.展开更多
基金Supported by NNSFC (No. 20372057) NSF of Jiangsu Province (No. BK2001142) Jiangsu Education Department (No. 01KJB150008) and the Key Lab of Biotechnology for Medicinal Plants of Jiangsu Province (02AXL 14)
文摘The title compound 2-amino-3-ethoxycarbonyl-4-(4-chlorophenyl)-4H,5H-pyrano- [3,2-c]-benzopyran-5-one (C21H16ClNO5, Mr = 397.80) has been synthesized and characterized by X-ray crystallography. It crystallizes in triclinic, space group P1 with a = 5.756(1), b = 10.099(1), c = 17.106(3) ? a = 80.49(1), b = 83.13(1), g = 80.07(1), V = 961.8(2) ?, Dc = 1.374 g/cm3, = 0.231 mm-1, Z = 2, F(000) = 412, the final R = 0.0369 and wR = 0.0947. In the molecule the pyran ring is of boat conformation. The intermolecular hydrogen bonds of NH…O(5)(x+2, y+1, z+1) and NH…Cl (x+1, y1, z) as well as intramolecular hydrogen bond NH…O(5) are found.
基金The authors thank the National Natural Science Foundation of China (Nos. 21462038, 21362034) and Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education for the financial support of this work.
文摘The conjugate hydrocyanation of chalcone derivatives using ethyl cyanoacetate as an organic cyanide source at room temperature under open air and transition metal-free conditions was described. The protocol has advantages of using relatively cheap, less toxic, stable and easy-to-handle cyanating reagent, high yield, and mild reaction condi- tion.
文摘Comparative experiments show that ultrasonic irradiation reduces the reaction times and improves the yields in the di-alkylation and cyclo-di-alkylation of ethyl cyanoacetate under solid-liquid phase transfer conditions.
基金We appreciate the National Natural Science Foundation of China (No. 20962018, 20862015, 20762009 and 20562011) for supporting this research.
文摘An efficient enantioselective Michael addition of ethyl-2-cyanoacetate and diethyl malonate to α,β-unsaturated ketones catalyzed by a simple chiral Schiff base, and products were obtained in good yields at room temperature.
基金supported by the Foundation of the Surpassing Project of Jiangsu Province
文摘The title compound ethyl 2-(2-amino-3-ethoxycarbonyl-4H-benzopyran-4-yl) cyanoacetate(C17H18N2O5, Mr=330.33) was obtained by the reaction of salicylaldehyde with ethyl cyanoacetate in DMF at room temperature catalyzed by KF-Al2O3. The crystal is monoclinic, space group P21/n, with unit cell constants a =9.277(3), b =8.521(2), c =21.320(2)? b =93.72(2)? Z =4, V =1681.8(7)?, Dc =1.305g/cm3, m (MoKa) =0.097mm-1, F(000) =696, R =0.0426, Rw =0.0970 for 3042 observed reflections(I>2s(I)). X-ray analysis reveals that interatomic distance for C(8)C(9) is 1.359(3)? which shows that it is C=C double bond. In addition, there are hydrogen bonds in the molecule.