Synthesis, Tautomeric States and Crystal Structure of (Z)-Ethyl 2- Cyano-2-(3H-Quinazoline-4-ylidene) Acetate and (Z)-Ethyl 2-Cyano-2- (2-Methyl-3H-Quinazoline-4-ylidene) Acetate

Molecules

Muborak Tulyasheva²  BakhtiyorF. Rasulev¹  Akmal G. Tojiboev²  Kambarali K. Turgunov²  Bakhodir Tashkhodjaev²  NasrullaD. Abdullaev² 

[1] Institute of the Chemistry of Plant Substances AS RUz, Kh. Abdullaev str., 77, Tashkent, 700170, Uzbekistan. Fax: [phone]; E-mail

关键词: Quinazolines;    activated methylene groups;    intramolecular hydrogen bonding;    tautomery;    quantum-chemical calculations;   

DOI  :  10.3390/10091209

来源: mdpi

【 摘 要 】

The new compounds (Z)-ethyl 2-cyano-2-(3H- and 2-methyl-3H-quinazoline- 4-ylidene) acetate (1 and 2, respectively) were synthesized by multi-step reactions. The structures in a solution have been determined by ¹H-NMR spectroscopy and in the crystal form by X-ray analysis. Molecule 1 crystallized in a primitive monoclinic cell, space group Р2₁/c. The cell dimensions are a=7.970(6) Å, b=7.061(2) Å, c=20.537(7) Å, β=97.69(5)°, V=1145.3(10) ų. Molecule 2 crystallized in a triclinic cell, space group P1, the cell dimensions are a=8.196(5) Å, b=8.997(6) Å, c=9.435(4) Å, α=74.22(4)°, β=89.75(4)°, γ=74.07(5)°, V=641.9(6) ų. In both compounds the presence of intramolecular NH---O=C hydrogen bonding between the nitrogen atom in position 3 of the quinazoline ring and a carbonyl group of the ethyl cyanoacetate residue was proven by quantum-chemical, ¹H-NMR and X-ray methods.

【 授权许可】

Unknown   
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