The crystal structures of two intermediates, 4-amino-3,5-difluorobenzonitrile, C7H4F2N2(I), and ethyl 4-amino-3,5-difluorobenzoate, C9H9F2NO2(II), along with a visible-light-responsive azobenzene derivative, diethyl 4,4′-(diazene-1,2-diyl)bis(3,5-difluorobenzoate), C18H14F4N2O4(III), obtained by four-step synthetic procedure, were studied using single-crystal X-ray diffraction. The molecules ofIandIIdemonstrate the quinoid character of phenyl rings accompanied by the distortion of bond angles related to the presence of fluorine substituents in the 3 and 5 (ortho) positions. In the crystals ofIandII, the molecules are connected by N—H...N, N—H...F and N—H...O hydrogen bonds, C—H...F short contacts, and π-stacking interactions. In crystal ofIII, only stacking interactions between the molecules are found.
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Crystal structure of (6,9-diacetyl-5,10,15,20-tetraphenylsecochlorinato)nickel(II)
Title compound1Ni, [Ni(C46H32N4O2)], a secochlorin nickel complex, was prepared by diol cleavage of a precursortrans-dihydroxydimethylchlorin. Two crystallographically independent molecules in the structure are related by pseudo-A lattice centering, with molecules differing mainly by a rotation of one of the acetyls and an adjacent phenyl groups. The two molecules have virtually identical conformations characterized by noticeable in-plane deformation in the A1gmode and a prominent out-of-plane deformation in the B1u(ruffling) mode. Directional interactions between molecules are scarce, limited to just a few C—H...O contacts, and intermolecular interactions are mostly dispersive in nature.
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- Award ID(s):
- 1800361
- PAR ID:
- 10539769
- Publisher / Repository:
- IUCR
- Date Published:
- Journal Name:
- Acta Crystallographica Section E Crystallographic Communications
- Volume:
- 80
- Issue:
- 6
- ISSN:
- 2056-9890
- Page Range / eLocation ID:
- 649 to 653
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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