Three closely related 1-[(1,3-benzodioxol-5-yl)methyl]-4-(halobenzo-yl)piperazines: similar mol-ecular structures but different inter-molecular inter-actions.

ABSTRACT: In each of the compounds 1-[(1,3-benzodioxol-5-yl)methyl]-4-(3-fluoro-benzo-yl)piperazine, C₁₉H₁₉FN₂O₃ (I), 1-[(1,3-benzodioxol-5-yl)methyl]-4-(2,6-di-fluoro-benzo-yl)piperazine, C₁₉H₁₈F₂N₂O₃ (II), and 1-[(1,3-benzodioxol-5-yl)methyl]-4-(2,4-di-chloro-benzo-yl)piperazine, C₁₉H₁₉Cl₂N₂O₃ (III), the piperazine rings adopt a chair conformation with the (1,3-benzodioxol-5-yl)methyl substituent occupying an equatorial site: the five-membered rings are all slightly folded across the O?O line leading to envelope conformations. The dihedral angle between the planar amidic fragment and the haloaryl ring is 62.97?(5)° in (I) but 77.72?(12)° and 75.50?(5)° in (II) and (III), respectively. Despite their similarity in constitution and conformation, the supra-molecular inter-actions in (I)-(III) differ: in (I), a combination of C-H?O and C-H??(arene) hydrogen bonds links the mol-ecules into a three-dimensional framework structure, but there are no hydrogen bonds of any sort in either (II) or (III), although the structure of (III) contains a short Cl?Cl contact between inversion-related pairs of mol-ecules.

SUBMITTER: Mahesha N 

PROVIDER: S-EPMC6362650 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature