title: Supramolecular networks in (9-fluoro-4H-chromeno[4,3-c]isoxazol-3-yl)methanol and its 9-chloro analogue at 100 K.
abstract: The title compounds, (9-fluoro-4H-chromeno[4,3-c]isoxazol-3-yl)methanol, C(11)H(8)FNO(3), (I), and (9-chloro-4H-chromeno[4,3-c]isoxazol-3-yl)methanol, C(11)H(8)ClNO(3), (II), crystallize in the orthorhombic space group Pbca with Z' = 1 and the triclinic space group P-1 with Z' = 6, respectively. The simple replacement of F by Cl in the main molecular scaffold of (I) and (II) results in significant differences in the intermolecular interaction patterns and a corresponding change in the point-group symmetry from D(2h) to C(i) = S(2). These striking differences are manifested through the presence of C-H···F and the absence of O-H···O and C-H···O interactions in (I), and the absence of C-H···Cl and the presence of O-H···O and C-H···O interactions in (II). However, the geometry of the synthons formed by the O-H···N and O-H···X (X = F or Cl) interactions observed in the constitution of the supramolecular networks of both (I) and (II) remains similar. Also, C-H···O interactions are not preferred in the presence of F in (I), while they are much preferred in the presence of Cl in (II).
authors.affiliation: Department of Physics, Thiagarajar College, Madurai, India.
authors.forename: P
authors.initials: P
authors.lastname: Rajalakshmi
authors.forename: N
authors.initials: N
authors.lastname: Srinivasan
authors.forename: R V
authors.initials: RV
authors.lastname: Krishnakumar
authors.forename: Ibrahim Abdul
authors.initials: IA
authors.lastname: Razak
authors.forename: Mohd Mustaqim
authors.initials: MM
authors.lastname: Rosli
mesh_terms: D001578:Benzopyrans / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D007555:Isoxazoles / Q000737:chemistry*; D015394:Molecular Structure
chemical_list: C576083:(9-chloro-4H-chromeno(4,3-c)isoxazol-3-yl)methanol; C576082:(9-fluoro-4H-chromeno(4,3-c)isoxazol-3-yl)methanol; D001578:Benzopyrans; D007555:Isoxazoles