95164-99-1Relevant academic research and scientific papers
Probable Absence of Lattice Control of cis-trans-Isomerization in 2-Ethoxy-cis-cinnamic Acid
Bryan, Robert F.,Hartley, Paul
, p. 191 - 194 (2007/10/02)
The crystal structure of the title compound has been determined from 1380 reflections measured by diffractometer.Crystals are orthorhombic, space group Pbca, with a=10.811(3), b=12.137(3), c=15.233(4) Angstroem, Z=8.The structure was solved by direct methods and refined by least-squares to give R 0.041.The acid is present in the crystal in a non-planar conformation and forms centrosymmetric hydrogen-bonded dimers (O-H...O, 2.651 Angstroem).The plane of the double bound, C(1)-C(β)-C(α)-C(7), is inclined to the plane of the phenyl ring at 59.4 deg, and to that of the carboxy-group at 12.3 deg.There is a limiting intramolecular contact between the carbonyl oxygen O(1) and C(6) of the phenyl ring.It has been postulated that the solid-state cis-trans isomerization of such cinnamic acids is lattice controlled, through interactions between >C=C bonds in neighbouring molecules in close contact (4.0-4.4 Angstroem).It is shown that this crystal, where isomerization is known to occur, contains no such suitable contacts.
