Structures of 1-hydrophenanthroimidazoles: building blocks in the synthesis of expanded-ring bis(imidazoles)

Abstract

The structures of 1H-phenanthro[9,10-d]imidazole, C15H10N2, (I), and 3,6-dibromo-1H-phenanthro[9,10-d]imidazole hemihydrate, C15H8Br2N(2).0.5H2O, (II), contain hydrogen-bonded polymeric chains linked by columns of pi-pi stacked essentially planar phenanthroimidazole monomers. In the structure of (I), the asymmetric unit consists of two independent molecules, denoted (Ia) and (Ib), of 1H-phenanthro[9,10-d]imidazole. Alternating molecules of (Ia) and (Ib), canted by 79.07 (3) degrees, form hydrogen-bonded zigzag polymer chains along the a-cell direction. The chains are linked by pi-pi stacking of molecules of (Ia) and (Ib) along the b-cell direction. In the structure of (II), the asymmetric unit consists of two independent molecules of 3,6-dibromo-1H-phenanthro[9,10-d]imidazole, denoted (IIa) and (IIb), along with a molecule of water. Alternating molecules of (IIa), (IIb) and water form hydrogen-bonded polymer chains along the [110] direction. The donor-acceptor distances in these N(imine)...H-O(water)...H-N(amine) hydrogen bonds are the shortest thus far reported for imidazole amine and imine hydrogen-bond interactions with water. Centrosymmetrically related molecules of (IIa) and (IIb) alternate in columns along the a-cell direction and are canted by 48.27 (3) degrees. The present study provides the first examples of structurally characterized 1H-phenanthroimidazoles.

Ethyl 7-oxo-7H-benzo[de]imidazo[5,1-a]isoquinoline-11-carboxylate–trifluoroacetic acid (1/1)

“…For their use as agents to study electron transfer, see: Knapp et al (1990). For related structures, see: Baugh et al (2006); Stibrany (2003); Stibrany et al (2002Stibrany et al ( , 2004; Stibrany & Potenza (2008, 2009; Gorun et al (1996).…”

“…Our investigation into the synthesis of acenapthoimidazoles as building blocks for higher dentate ligands led us to attempt a similar method of preparation as for phenanthroimidazoles (Stibrany & Potenza, 2009). The title compound was isolated by chromatography as a side product of that preparation.…”

A second monoclinic polymorph of {bis[5-methyl-3-(trifluoromethyl)pyrazol-1-yl]borato}{tris[5-methyl-3-(trifluoromethyl)pyrazol-1-yl]borato}cobalt(II): a structure containing a B—H...Co agostic interaction

“…Our long-term interest in the synthesis and applications of nitrogen-containing heterocyles, such as expanded-ring imidazoles, and their complexes with metal ions (Stibrany & Potenza, 2009a) led us to prepare the title compound (I).…”

{Bis[5-methyl-3-(trifluoromethyl)pyrazol-1-yl]borato}{tris[5-methyl-3-(trifluoromethyl)pyrazol-1-yl]borato}cobalt(II): a structure containing a B—H...Co agostic interaction

“…For our study of nitrogen-containing heterocyles, such as expanded-ring imidazoles, and their complexes with metal ions, see: Stibrany & Potenza (2009a). For metal complexes with pyrazole, see: , 2009b; Stibrany et al (1999Stibrany et al ( , 2005.…”