Crystal structures and FT-IR spectra of three N,N-dicyclohexylmethylammonium halides C13H26N+ X − (X = Cl, Br, I)

Abstract

Abstract The title compounds C13H26N+Cl− (N,N-dicyclohexylmethylammonium chloride), C13H26N+Br− (N,N- dicyclohexylmethylammonium bromide) and C13H26N+I− (N,N-dicyclohexylmethylammonium iodide) are isostructural and crystallize in the orthorhombic space group Pna21 with the lattice parameters a=7.580(1), b=19.072(1), c=9.165(1) Å, V=1324.9(1) Å3 for X=Cl, a=7.765(1), b=19.054(1), c=9.270(1) Å, V=1371.5(1) Å3 for X=Br, and a=8.102(1), b=19.084(1), c=9.535(1) Å, V=1474.2(1) Å3 for X=I with Z=4 for each compound. Their cyclohexyl groups are aligned along [010] while their halide ions are coordinated along [100] by a strong linear N–H···X (X=Cl, Br, I) hydrogen bond. Fourier-transform infrared spectra show a decreasing hydrogen bond acceptor strength from the chloride to the iodide.