R. Centore, M. R. Ciajolo, A. Tuzi
Dec 1, 1993
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0
Influential Citations
5
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Journal
Molecular Crystals and Liquid Crystals
Abstract
Abstract Bis[4-(4′-carboxy-butanoyloxy)-acetophenon azine(C26H28O8N2) is a dicarboxylic acid that can be considered as a model for semiflexible mesogenic polyesters having formula [‒COO‒R‒OOC‒(CH2)2n- x, with R = ‒ϕ‒C(CH3)˭N˭N˭C(CH3)‒ϕ‒ (‒ϕ- = p-phenylene). It has been synthesized and its crystal structure has been determined by direct methods. Crystals are triclinic, space group P1, a = 6.306(2), b = 7.738(2), c = 25.982(6) A, α = 96.93(2)°, β = 93.16(4)°, γ = 93.93(3)° with two molecules in the unit cell. The structure was refined by full matrix least squares methods to R = 0.084 for 1962 observed reflections, having I > 2.5 σ(I). The structure is affected by positional disorder on one of the two terminal chains of the molecule. The conformation around the central ˭N˭N˭ bond of the crystallographic independent molecule is not trans planar. The average planes of the phenyl rings belonging to the same molecule make a dihedral angle of 62.6°. Molecules are linked through hydrogen bonds between carboxylic g...