Analysis of Small Molecule X-Ray Crystal Structures: Chemical Crystallography with Undergraduate Students in a Teaching Laboratory

Abstract

The molecular structures of six small molecule organic compounds have been studied by X-ray diffraction in collaboration with undergraduate students enrolled in an advanced integrated laboratory course. The structures of 3-chloro-2-fluorobenzonitrile (1) [orthorhombic, P212121, a = 3.7679(13) A, b = 12.546(4) A, c = 13.780(5) A], 5-chloro-2-fluorobenzonitrile (2) [monoclinic, P21/c, a = 3.7909(7) A, b = 14.265(3) A, c = 12.171(2) A, β = 92.314(3)°], 2-bromo-3′-hydroxyacetophenone (3) [triclinic, P-1, a = 7.7081(3) A, b = 9.8840(3) A, c = 10.7320(4) A, α = 98.4345(4)°, β = 90.6184(4)°, γ = 105.9259(4)°], 3-chlorobenzoylacetonitrile (4) [monoclinic, Cc, a = 4.8086(6) A, b = 32.929(4) A, c = 10.5855(13) A, β = 97.665(1)°], 4-bromo-1-indanone (5) [triclinic, P-1, a = 7.3731(4) A, b = 7.5419(4) A, c = 8.2370(4) A, α = 62.927(1)°, β = 71.160(1)°, γ = 71.521(1)°], and 4-bromo-1-indanol (6) [monoclinic, P21/c, a = 12.7914(9) A, b = 4.6949(4) A, c = 27.864(2) A, β = 94.707(1)°] reveal several different types of intermolecular interactions, such as hydrogen bonding, π-stacking, halogen–halogen interactions, and C–H···X (X = O, N, halogen) interactions. The molecular structures of six small molecule organic compounds have been studied by X-ray diffraction in collaboration with undergraduate students enrolled in an advanced integrated laboratory course. The structures reveal several different types of intermolecular interactions, such as hydrogen bonding, π-stacking, halogen–halogen interactions, and C–H···X (X = O, N, halogen) interactions.