(1R,4S)-7,8-Dichloro-1,2,3,4-tetra­hydro-1,11,11-trimethyl-1,4-methano­phenazine

The title compound, C16H16Cl2N2, was synthesized by the condensation reaction between 4,5-dichloro-o-phenyl­ene­diamine and (1R)-(-)-camphorquinone in boiling acetic acid. The two crystallographically independent mol­ecules in the unit cell are related by a pseudo-inversion center

2-(2-Chloro­phen­yl)-3-(3,4-dimeth­oxy­phen­yl)quinoxaline

The title compound, C22H17ClN2O2, was synthesized by the condensation reaction between 1,2-phenyl­enediamine and 2-chloro-3′,4′-dimeth­oxy­benzil in boiling acetic acid. The chloro­phenyl and dimeth­oxy­phenyl rings make dihedral angles of 78.45 (5) and 35.60 (4)°, respectively, with the quinoxaline unit

(1S,4R)-1,11,11-Trimethyl-1,2,3,4-tetrahydro-1,4-methanophenazine N5-oxide

The title compound, C16H18N2O, was synthesized via reaction of (1S,4R)-1,2,3,4-tetrahydro-1,11,11-trimethyl-1,4-methanophenazine with 3-chloroperbenzoic acid in dichloromethane. The absolute configuration for the product was assigned based on the stereochemistry of the camphorquinone reactant

11,12-Dichlorodibenzo[a,c]phenazine

The title compound, C20H10Cl2N2, has crystallographic twofold rotational symmetry [maximum deviation from the least-squares plane = 0.038 (1) Å]. In the crystal, weak π–π ring stacking interactions occur down the a-axis direction [minimum centroid–centroid separation = 3.7163 (8) Å]

6,7-Dichloro-2,3-bis(pyridin-2-yl)quinoxaline

The title compound, C18H10Cl2N4, synthesized by the condensation reaction between 4,5-dichlorobenzene-1,2-diamine and 1,2-di(pyridin-2-yl)ethane-1,2-dione in boiling acetic acid, has a nearly planar quinoxaline moiety [maximum deviation = 0.070 (1) Å] whose mean plane makes dihedral angles of 40.51 (2) and 39.29 (3)° with the pyridine rings. Within the unit cell, there are no classical hydrogen bonds. Molecules in the structure pack with π–π stacking contacts between the quinoxaline units and nearby pyridine rings with an intercentroid distance of 3.7676 (9) Å

N-(4-Chlorophenyl)-9H-fluoren-9-imine

The title compound, C19H12ClN, was synthesized via reaction of 9-fluorenone and 4-chloroaniline using p-toluenesulfonic acid in toluene. The dihedral angle between the fluorene moiety (r.m.s. deviation = 0.027 Å) and the chlorophenyl ring is 64.59 (6)° and a possible weak intramolecular C—H...π interaction occurs