Structural characterization and Hirshfeld surface analysis of racemic baclofen

• The first single crystal structure of baclofen.
• The molecules exist as zwitterions, adopting a gauche conformation with respect to the CαCβ bond.
• The crystal packing is governed mainly by NH⋯O and CCl⋯π interactions.

The crystal structure of baclofen, (R,S) [4-amino-3-(4-chlorophenyl)butanoic acid], (C10H12ClNO2, Mr = 213.66) has been determined by single crystal X-ray diffraction analysis. The title compound crystallizes in the orthorhombic space group Pbca (No. 61) with a = 9.2704(5), b = 7.0397(4), c = 30.4015(15) Å, V = 1984.0(2) Å3 and Z = 8. The molecules exist as zwitterions, adopting a gauche conformation with respect to the CαCβ bond, and held in a cross-linked chain arrangement by strong NH⋯O hydrogen bonds and CCl⋯π interactions. The electrostatic molecular potential as well as the intermolecular interactions of the title compound were analyzed by the Hirshfeld surfaces. The FT-IR spectrum is also reported. The DTA, TG and DTG results indicate that baclofen is stable up to 205 °C.

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