Abstract
In the title compound, C10H4Cl2O3, a dichlorinated 3-formyl-chromone derivative, the fused-ring system is slightly puckered [dihedral angle between the benzene and pyran rings = 3.66 (10)°]. The dihedral angle between the pyran ring and the formyl plane is 8.64 (7)°. In the crystal, mol-ecules are linked through π-π stacking inter-actions [centroid-centroid distance between the benzene and pyran rings = 3.727 (2) Å], C-H⋯O hydrogen bonds and short C⋯O contacts [2.838 (4) Å]. Halogen bonds between the formyl O atoms and the Cl atoms at the 7-position [Cl⋯O = 2.984 (3) Å, C-Cl⋯O = 170.83 (12)° and Cl⋯O-C = 116.05 (19)°] are also formed along the a axis, resulting in helical structures constructed by C-H⋯O hydrogen bonds and Cl⋯O halogen bonds along the b axis. In addition, type II halogen-halogen contacts between the chlorine atoms at the 7- and 8-positions [Cl⋯Cl = 3.519 (2) Å, C-Cl⋯Cl = 171.24 (10)° and 88.74 (11)°] are observed.
Highlights
In the title compound, C10H4Cl2O3, a dichlorinated 3-formylchromone derivative, the fused-ring system is slightly puckered [dihedral angle between the benzene and pyran rings = 3.66 (10) ]
Halogen bonding is defined as a net attractive interaction between an electrophilic region of a halogen atom in a molecule and a nucleophilic region of an atom in a molecule, and is characterized by a short contact between the two atoms
Halogen–halogen interactions are generally classified into two categories, type I (1 = 2) and type II (1 = 180, 2 = 90) where
Summary
Halogen bonding and halogen–halogen interactions have recently attracted much attention in medicinal chemistry, chemical biology, supramolecular chemistry and crystal engineering (Auffinger et al, 2004; Metrangolo et al, 2005; Wilcken et al, 2013; Sirimulla et al, 2013; Persch et al, 2015). Halogen bonding is defined as a net attractive interaction between an electrophilic region of a halogen atom in a molecule and a nucleophilic region of an atom in a molecule, and is characterized by a short contact between the two atoms. The type I contact is considered to be van der Waals, and the type II is halogen bonding, i.e., an electrostatic interaction (Mukherjee et al., 2014; Metrangolo et al, 2014). As for the monochlorinated 3-formylchromones, a type I van der Waals contact is observed in 7-chloro-4-oxo-4H-chrodoi:10.1107/S205698901501275X.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
