title: 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.
abstract: 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 (1)H-NMR spectroscopy and in the crystal form by X-ray analysis. Molecule 1 crystallized in a primitive monoclinic cell, space group capital ER, P2(1/c). The cell dimensions are a=7.970(6) A, b=7.061(2) A, c=20.537(7) A, beta=97.69(5) degrees , V=1145.3(10) A(3). Molecule 2 crystallized in a triclinic cell, space group P-1, the cell dimensions are a=8.196(5) A, b=8.997(6) A, c=9.435(4) A, alpha=74.22(4) degrees, beta=89.75(4) degrees , gamma=74.07(5) degrees , V=641.9(6) A(3). In both compounds the presence of intra-molecular 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, (1)H-NMR and X-ray methods.
authors.affiliation: Institute of the Chemistry of Plant Substances AS RUz, Uzbekistan. tulyasheva@yahoo.com
authors.forename: Muborak
authors.initials: M
authors.lastname: Tulyasheva
authors.forename: Bakhtiyor F
authors.initials: BF
authors.lastname: Rasulev
authors.forename: Akmal G
authors.initials: AG
authors.lastname: Tojiboev
authors.forename: Kambarali K
authors.initials: KK
authors.lastname: Turgunov
authors.forename: Bakhodir
authors.initials: B
authors.lastname: Tashkhodjaev
authors.forename: Nasrulla D
authors.initials: ND
authors.lastname: Abdullaev
authors.forename: Khusnutdin M
authors.initials: KM
authors.lastname: Shakhidoyatov
mesh_terms: D000085:Acetates / Q000138:chemical synthesis* / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D011799:Quinazolines / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: C525097:(Z)-ethyl 2-cyano-2-(2-methyl-3H-quinazoline-4-ylidene) acetate; C525098:(Z)-ethyl 2-cyano-2-(3H-quinazoline-4-ylidene) acetate; D000085:Acetates; D011799:Quinazolines