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Published on: November 18, 2015
Crystal structure of 7,8-benzocoumarin-4-acetic acid
R Ranga Swamy1, Ramakrishna Gowda2, K V Arjuna Gowda3
1Department of Physics, Sri Krishna Rajendra Silver Jubilee Institute of Technology, Bangalore 560 001, Karnataka, India.
Abstract:
The fused-ring system in the title compound [systematic name: 2-(2-oxo-2H-benzo[h]chromen-4-yl)acetic acid], C15H10O4, is almost planar (r.m.s. deviation = 0.031 Å) and the Car-C-C=O (ar = aromatic) torsion angle for the side chain is -134.4 (3)°. In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, generating [100] C(8) chains, where the acceptor atom is the exocyclic O atom of the fused-ring system. The packing is consolidated by a very weak C-H⋯O hydrogen bond to the same acceptor atom. Together, these inter-actions lead to undulating (001) layers in the crystal.
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