title: Comparison of the crystal structures of methyl 4-bromo-2-(meth-oxy-meth-oxy)benzoate and 4-bromo-3-(meth-oxy-meth-oxy)benzoic acid.
abstract: The title compounds, C10H11BrO4, (I), and C9H9BrO4, (II), are derivatives of bromo-hy-droxy-benzoic acids. Compound (II) crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. In both (I) and (II), the O-CH2-O-CH3 side chain is not in its fully extended conformation; the O-C-O-C torsion angle is 67.3 (3) ° in (I), and -65.8 (3) and -74.1 (3)° in mol-ecules A and B, respectively, in compound (II). In the crystal of (I), mol-ecules are linked by C-H⋯O hydrogen bonds, forming C(5) chains along [010]. The chains are linked by short Br⋯O contacts [3.047 (2) Å], forming sheets parallel to the bc plane. The sheets are linked via C-H⋯π inter-actions, forming a three-dimensional architecture. In the crystal of (II), mol-ecules A and B are linked to form R 2 (2)(8) dimers via two strong O-H⋯O hydrogen bonds. These dimers are linked into ⋯A-B⋯A-B⋯A-B⋯ [C 2 (2)(15)] chains along [011] by C-H⋯O hydrogen bonds. The chains are linked by slipped parallel π-π inter-actions [inter-centroid distances = 3.6787 (18) and 3.8431 (17) Å], leading to the formation of slabs parallel to the bc plane.
authors.affiliation: Department of Chemistry, University College of Science, Tumkur University, Tumkur 572 103, India.
authors.forename: P A
authors.initials: PA
authors.lastname: Suchetan
authors.affiliation: Department of Chemistry, Bapatla Engineering College (Autonomous), Bapatla A. P., India.
authors.forename: V
authors.initials: V
authors.lastname: Suneetha
authors.affiliation: Institution of Excellence, University of Mysore, Manasagangotri, Mysuru-6, India.
authors.forename: S
authors.initials: S
authors.lastname: Naveen
authors.affiliation: Department of Physics, University of Mysore, Manasagangotri, Mysuru-6, India.
authors.forename: N K
authors.initials: NK
authors.lastname: Lokanath
authors.affiliation: Department of Chemistry, Bapatla Engineering College (Autonomous), Bapatla A. P., India.
authors.forename: P
authors.initials: P
authors.lastname: Krishna Murthy
keywords: C—H⋯πar­yl inter­actions; bromo hy­droxy benzoic acids; crystal structure; hydrogen bonding; π–π inter­actions