title: Dihydrooxazolones and dihydroimidazolones derived from acylglycines: syntheses, molecular structures and supramolecular assembly.
abstract: Syntheses and structures are described for some alkylidene-substituted dihydrooxazolones and dihydroimidazoles derived from simple acylglycines. A second, triclinic, polymorph of 4-benzylidene-2-(4-methylphenyl)-1,3-oxazol-5(4H)-one, C17H13NO2, (I), has been identified and the structure of 2-methyl-4-[(thiophen-2-yl)methylidene]-1,3-oxazol-5(4H)-one, C9H7NO2S, (II), has been rerefined taking into account the orientational disorder of the thienyl group in each of the two independent molecules. The reactions of phenylhydrazine with 2-phenyl-4-[(thiophen-2-yl)methylidene]-1,3-oxazol-5(4H)-one or 2-(4-methylphenyl)-4-[(thiophen-2-yl)methylidene]-1,3-oxazol-5(4H)-one yield, respectively, 3-anilino-2-phenyl-5-[(thiophen-2-yl)methylidene]-3,5-dihydro-4H-imidazol-4-one, C10H15N3OS, (III), and 3-anilino-2-(4-methylphenyl)-5-[(thiophen-2-yl)methylidene]-3,5-dihydro-4H-imidazol-4-one, C21H17N3OS, (IV), which both exhibit orientational disorder in their thienyl groups. The reactions of 2-phenyl-4-[(thiophen-2-yl)methylidene]-1,3-oxazol-5(4H)-one with hydrazine hydrate or with water yield, respectively, N-[3-hydrazinyl-3-oxo-1-(thiophen-2-yl)prop-1-en-2-yl]benzamide and 2-(benzoylamino)-3-(thiophen-2-yl)prop-2-enoic acid, which in turn react, respectively, with thiophene-2-carbaldehyde to form 2-phenyl-5-[(thiophen-2-yl)methylidene]-3-{[(E)-(thiophen-2-yl)methylidene]amino}-3,5-dihydro-4H-imidazol-4-one, C19H13N3OS2, (V), which exhibits orientational disorder in only one of its thienyl groups, and with methanol to give methyl (2Z)-2-(benzoylamino)-3-(thiophen-2-yl)prop-2-enoate, C15H13NO3S, (VI). There are no direction-specific intermolecular interactions in the crystal structure of the triclinic polymorph of (I), but the molecules of (II) are linked by two independent C-H···O hydrogen bonds to form C2(2)(14) chains. Compounds (III) and (IV) both form centrosymmetric R2(2)(10) dimers built from N-H···O hydrogen bonds, while compound (V) forms a centrosymmetric R2(2)(10) dimer built from C-H···O hydrogen bonds. In the structure of compound (VI), a combination of N-H···O and C-H···π(arene) hydrogen bonds links the molecules into sheets. Comparisons are made with some similar compounds.
authors.affiliation: Department of Chemistry, Mangalore University, Mangalagangotri 574 199, D.K., Mangalore, India.
authors.forename: Karanth N
authors.initials: KN
authors.lastname: Subbulakshmi
authors.affiliation: Department of Chemistry, Mangalore University, Mangalagangotri 574 199, D.K., Mangalore, India.
authors.forename: Badiadka
authors.initials: B
authors.lastname: Narayana
authors.affiliation: Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India.
authors.forename: Hemmige S
authors.initials: HS
authors.lastname: Yathirajan
authors.affiliation: Department of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Akkurt
authors.affiliation: Department of Physics, Faculty of Education, Dicle University, 21280 Diyarbakir, Turkey.
authors.forename: Ömer
authors.initials: Ö
authors.lastname: Çelik
authors.affiliation: Department of Physics, Faculty of Arts and Sciences, Sinop University, 57010 Sinop, Turkey.
authors.forename: Cem Cüneyt
authors.initials: CC
authors.lastname: Ersanlı
authors.affiliation: School of Chemistry, University of St Andrews, Fife KY16 9ST, Scotland.
authors.forename: Christopher
authors.initials: C
authors.lastname: Glidewell
mesh_terms: D001597:Benzylidene Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D005998:Glycine / Q000737:chemistry*; D006860:Hydrogen Bonding; D007093:Imidazoles / Q000737:chemistry*; D015394:Molecular Structure; D010081:Oxazolone / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: C000602693:4-benzylidene-2-(4-methylphenyl)-1,3-oxazol-5(4H)-one; D001597:Benzylidene Compounds; D007093:Imidazoles; C117197:imidazolone; D010081:Oxazolone; D005998:Glycine
keywords: Erlenmeyer azlactones; crystal structure; hydrogen bonding; imidazolones; orientational disorder; oxazolones; supramolecular assembly