3,5-Dichloro-4-cyanobenzoic Acid Co-crystals with Carbon Tetrachloride, Naphthalene, and Anthracene

Abstract

The title compound, C₈H₃Cl₂NO₂ (M), forms co-crystals with carbon tetrachloride, M/CCl₄; naphthalene, M/1/2C₁₀H₈; and anthracene, M/1/2C₁₄H₁₀. Cell parameters for M/CCl₄: a = 8.8657(10) Å, b = 8.9393(10) Å, c = 10.2658(12) Å, α = 66.622(2)°, β = 69.510(2)°, γ = 71.968(2)°, space group P-1. Cell parameters for M/1/2C₁₀H₈: a = 8.0304(13) Å, b = 9.0112(14) Å, c = 9.4742(15) Å, α = 112.282(3)°, β = 100.378(3)°, γ = 91.968(3)°, space group P-1. Cell parameters for M/1/2C₁₄H₁₀ a = 5.8893(7) Å, b = 7.3885(9) Å, c = 15.4098(18) Å, α = 87.972(2)°, β = 82.242(2)°, γ = 78.085(2)°, space group P-1. In each case the benzoic acid groups interact to form dimers of M with an R ²₂ (8) motif. The dimers are linked together through CN···Cl intermolecular interactions with an R ²₂ (10) motif to form chains or sheets. With the exception of one CN···CCl₄ interaction, the other molecule in each co-crystal is packed between chains (carbon tetrachloride) or in holes in the sheets (naphthalene and anthracene).

Graphical Abstract

3,5-Dichloro-4-cyanobenzoic, which has interwoven sheets in the pure state, can be directed into planar layers, with a co-crystalline partner.