A new polymorph of (E)-4-bromo-2-((phenylimino)methyl)phenol is reported together with a low temperature structure determination of the previously published polymorph. Both polymorphs were found to have an intra¬molecular O—H···N hydrogen bond, between the phenol OH and imine N, forming an S(6) ring. The crystals were observed to be different colours at room temperature with the previously published polymorph being more orange and the new polymorph more yellow. The planarity of the molecule in the two polymorphs was found to be significantly different with dihedral angles (Φ) between the two aromatic rings for the previously published 'orange' polymorph of Φ = 1.8 (2)° at 120 K, while the new 'yellow' polymorph had Φ = 45.6 (1)° at 150 K. It was also observed that both polymorphs displayed some degree of thermochromism and upon cooling the 'orange' polymorph became more yellow, while the 'yellow' polymorph became paler upon cooling.
|Number of pages||11|
|Journal||Acta Crystallographica Section C: Crystal Structure Communications|
|Early online date||8 Oct 2020|
|Publication status||E-pub ahead of print - 8 Oct 2020|
- crystal structure