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

Crundwell, G.; Glagovich, N.

doi:10.1107/S1600536810044016

organic compounds

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ISSN: 2056-9890

Volume 66| Part 11| November 2010| Page o3042

https://doi.org/10.1107/S1600536810044016

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

Guy Crundwell ^a ^* and Neil Glagovich ^a

^aDepartment of Chemistry and Biochemistry, Central Connecticut State University, 1619 Stanley Street, New Britain, CT 06053, USA
^*Correspondence e-mail: crundwellg@ccsu.edu

(Received 8 October 2010; accepted 27 October 2010; online 31 October 2010)

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.

Related literature

Steel & Fitchett (2000 , 2006 ) illustrate the use of stereochemically active quinoxalines in extended metal–ligand networks.

Experimental

Crystal data

C₁₆H₁₆Cl₂N₂
M_r = 307.21
Monoclinic, P 2₁
a = 6.9741 (3) Å
b = 13.0892 (5) Å
c = 16.9594 (5) Å
β = 101.701 (3)°
V = 1515.97 (10) Å³
Z = 4
Mo Kα radiation
μ = 0.42 mm⁻¹
T = 293 K
0.32 × 0.18 × 0.11 mm

Data collection

Oxford Xcalibur Sapphire3 diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD, CrysAlis RED and CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ) T_min = 0.897, T_max = 1.000
42674 measured reflections
12344 independent reflections
7343 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.058
wR(F²) = 0.163
S = 0.93
12344 reflections
367 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.18 e Å⁻³
Absolute structure: Flack (1983 ), with 5825 Friedel pairs
Flack parameter: 0.03 (5)

Data collection: CrysAlis CCD (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD, CrysAlis RED and CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD, CrysAlis RED and CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ), Mercury (Macrae et al., 2008 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810044016/zl2314sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810044016/zl2314Isup2.hkl

checkCIF report

Comment top

Nitrogen-containing aromatic heterocycles have often been used as ligands in one-, two-, and three dimensional metal–organic coordination polymers. There has been interest in developing chiral nitrogen-containing aromatic heterocycles in order to have greater design control over the assembly of these extended networks in the solid state (Steel & Fitchett, 2000). As a subset of nitrogen-containing aromatic heterocycles, quinoxalines, pyrazino[2,3-g]quinoxalines, and phenazines have shown the ability to bind to a variety of metals and are, as ligands, easy to synthesize via condensation reactions between ethanediones/quinones and diamines/tetraamines (Steel & Fitchett, 2006). In this paper we report the synthesis and structure of the chiral (1R,4S)-7,8-dichloro-1,2,3,4-tetrahydro-1,11,11-trimethyl-1,4-methanophenazine.

The title compound crystallizes in a chiral setting in the space group P2₁ with two crystallographically independent molecules in the asymmetric unit, Fig. 1. The two molecules are closely related by a pseudo inversion center located near coordinates x = 0.263, y = 0.461, z = 0.252. All bond distances and angles fall within expected values and there are no classic hydrogen bonds; however as can be seen in Fig. 2, one of the molecules packs with a slight bend in the quinoxaline moiety. Fig. 3 shows the molecular overlay of the two molecules in the asymmetric unit.

Related literature top

Steel & Fitchett (2000, 2006) illustrate the use of stereochemically active quinoxalines in extended metal–ligand networks.

Experimental top

To a 150 ml round bottom flask equipped with a reflux condenser was added 2.9 g (0.0120 mol) (1R)-(-)-camphorquinone, 2.77 g (0.0156 mol) 4,5-dichloro-o-phenylenediamine, and 50 ml glacial acetic acid. The mixture was heated to reflux for 3 h, and was then poured over ice to precipitate the crude product. After isolation via vacuum filtration, the crude product was recrystallized from methanol to yield 2.79 g (0.00908 mol) 3,4-dichlorocamphorquinoxaline (75% yield).

MP (K): 422.3-424.0; IR (CHCl₃): 3086, 2051, 1521, 1404, 12635, 1166, 1118, 890, 876 cm^-1; ¹H NMR (300 MHz, CDCl₃): δ 8.13 (s, 1H), 8.06 (s, 1H), 3.04 (d, 1H, J = 4.6 Hz), 2.31 (dtd, 1H, J = 4.6 Hz, J = 8 Hz, J = 12 Hz), 2.06 (dq, 1H, J = 8 Hz, J = 12 Hz), 1.40 (s, 3H), 1.39 (q, 2H, J = 10 Hz), 1.11 (s, 3H), 0.60 (s, 3H); ¹³C NMR (300 MHz, CDCl₃): δ 166.8, 165.0, 140.4, 140.3, 132.2, 129.7, 129.5, 54.3, 54.0, 53.3, 31.8, 24.6, 20.4, 18.5, 10.0; UV/Vis (CH₂Cl₂; λ_max) 260, 267, 365; MS (calculated for C₁₆H₁₆Cl₂N₂): M⁺: 306, measured: 306.

Structure description top

Steel & Fitchett (2000, 2006) illustrate the use of stereochemically active quinoxalines in extended metal–ligand networks.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis CCD (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997), Mercury (Macrae et al., 2008) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. A view of (1R,4S)-7,8-Dichloro-1,2,3,4-tetrahydro-1,11,11- trimethyl-1,4-methanophenazine (Farrugia, 1997). There are two molecules in the asymmetric unit. Displacement ellipsoids are drawn at the 50% probability level. Labels for atoms C10 and C12 in the first molecule and atom C28 in the second molecule were omitted for clarity.
	Fig. 2. A view of the packing nearly along (100) showing both molecules as well as the slight quinoxaline plane bending in the first (Spek, 2009).
	Fig. 3. Molecular overlay of both molecules in the asymmetric unit showing the slight bend of molecule 1 [red] compared to molecule 2 [blue] (Macrae et al., 2008).

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

Crystal data top

C₁₆H₁₆Cl₂N₂	F(000) = 640
M_r = 307.21	D_x = 1.346 Mg m⁻³
Monoclinic, P2₁	Melting point: 422 K
Hall symbol: P 2yb	Mo Kα radiation, λ = 0.71073 Å
a = 6.9741 (3) Å	Cell parameters from 15315 reflections
b = 13.0892 (5) Å	θ = 4.2–35.0°
c = 16.9594 (5) Å	µ = 0.42 mm⁻¹
β = 101.701 (3)°	T = 293 K
V = 1515.97 (10) Å³	Block, white
Z = 4	0.32 × 0.18 × 0.11 mm

Data collection top

Oxford Xcalibur Sapphire3 diffractometer	12344 independent reflections
Radiation source: Enhance (Mo) X-ray Source	7343 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.032
Detector resolution: 16.1790 pixels mm^-1	θ_max = 35.0°, θ_min = 4.2°
ω scans	h = −11→11
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −20→20
T_min = 0.897, T_max = 1.000	l = −27→27
42674 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.058	H-atom parameters constrained
wR(F²) = 0.163	w = 1/[σ²(F_o²) + (0.0946P)² + 0.0917P] where P = (F_o² + 2F_c²)/3
S = 0.93	(Δ/σ)_max < 0.001
12344 reflections	Δρ_max = 0.42 e Å⁻³
367 parameters	Δρ_min = −0.18 e Å⁻³
1 restraint	Absolute structure: Flack (1983), with 5825 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.03 (5)

Crystal data top

C₁₆H₁₆Cl₂N₂	V = 1515.97 (10) Å³
M_r = 307.21	Z = 4
Monoclinic, P2₁	Mo Kα radiation
a = 6.9741 (3) Å	µ = 0.42 mm⁻¹
b = 13.0892 (5) Å	T = 293 K
c = 16.9594 (5) Å	0.32 × 0.18 × 0.11 mm
β = 101.701 (3)°

Data collection top

Oxford Xcalibur Sapphire3 diffractometer	12344 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	7343 reflections with I > 2σ(I)
T_min = 0.897, T_max = 1.000	R_int = 0.032
42674 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.058	H-atom parameters constrained
wR(F²) = 0.163	Δρ_max = 0.42 e Å⁻³
S = 0.93	Δρ_min = −0.18 e Å⁻³
12344 reflections	Absolute structure: Flack (1983), with 5825 Friedel pairs
367 parameters	Absolute structure parameter: 0.03 (5)
1 restraint

Special details top

Experimental. Absorption correction: CrysAlis Pro (Oxford Diffraction Ltd., 2009) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

Hydrogen atoms were included in calculated positions with a C—H distances of 0.93 Å, 0.96 Å, 0.97 Å, and 0.98 Å based upon type of carbon. Hydrogen atoms were included in the refinement in riding motion approximation with a U_iso of either 1.2U_eq or 1.5U_eq of the carrier atom depending upon type of carbon.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.1545 (3)	0.45050 (16)	0.49934 (12)	0.0398 (4)
N1	0.2970 (3)	0.42161 (16)	0.46481 (11)	0.0460 (4)
C2	0.2335 (3)	0.38885 (17)	0.38582 (12)	0.0402 (4)
C3	0.3738 (3)	0.35025 (19)	0.34450 (14)	0.0465 (5)
H3	0.5062	0.3515	0.3684	0.056*
C4	0.3134 (4)	0.31076 (17)	0.26865 (14)	0.0442 (5)
Cl1	0.48375 (11)	0.25649 (6)	0.22037 (4)	0.0677 (2)
C5	0.1167 (4)	0.31228 (18)	0.23080 (12)	0.0451 (5)
Cl2	0.03974 (13)	0.25733 (7)	0.13693 (4)	0.0764 (2)
C6	−0.0217 (4)	0.35345 (19)	0.26854 (13)	0.0471 (5)
H6	−0.1519	0.3572	0.2418	0.057*
C7	0.0347 (3)	0.39014 (16)	0.34825 (12)	0.0382 (4)
N2	−0.1129 (3)	0.42215 (15)	0.38665 (11)	0.0423 (4)
C8	−0.0476 (3)	0.45064 (16)	0.46059 (12)	0.0393 (4)
C9	−0.1600 (4)	0.48131 (19)	0.52398 (14)	0.0467 (5)
H9	−0.2939	0.5059	0.5043	0.056*
C10	−0.1369 (4)	0.38915 (18)	0.58179 (15)	0.0521 (5)
H10A	−0.1703	0.3259	0.5524	0.063*
H10B	−0.2196	0.3966	0.6211	0.063*
C11	0.0802 (4)	0.39084 (19)	0.62275 (14)	0.0534 (6)
H11A	0.1447	0.3281	0.6122	0.064*
H11B	0.0956	0.3994	0.6805	0.064*
C12	0.1656 (4)	0.48392 (19)	0.58474 (13)	0.0467 (5)
C13	0.3638 (5)	0.5211 (3)	0.62876 (18)	0.0753 (9)
H13A	0.4578	0.4670	0.6314	0.113*
H13B	0.3556	0.5416	0.6823	0.113*
H13C	0.4038	0.5782	0.6005	0.113*
C14	−0.0131 (4)	0.55950 (18)	0.57193 (13)	0.0489 (5)
C15	0.0151 (6)	0.6545 (2)	0.52444 (19)	0.0738 (9)
H15A	0.0376	0.6351	0.4725	0.111*
H15B	0.1258	0.6923	0.5529	0.111*
H15C	−0.1001	0.6963	0.5179	0.111*
C16	−0.0675 (5)	0.5936 (2)	0.65206 (17)	0.0650 (7)
H16A	0.0376	0.6334	0.6826	0.097*
H16B	−0.0892	0.5344	0.6825	0.097*
H16C	−0.1846	0.6341	0.6407	0.097*
C17	0.3327 (3)	0.43610 (18)	0.00994 (12)	0.0440 (5)
N3	0.1985 (3)	0.47672 (17)	0.04292 (11)	0.0496 (5)
C18	0.2727 (3)	0.52064 (17)	0.11783 (12)	0.0396 (4)
C19	0.1397 (3)	0.56594 (19)	0.15972 (13)	0.0459 (5)
H19	0.0066	0.5669	0.1370	0.055*
C20	0.2070 (3)	0.60867 (17)	0.23410 (13)	0.0426 (5)
Cl3	0.04203 (10)	0.66515 (6)	0.28452 (4)	0.06479 (19)
C21	0.4066 (4)	0.60690 (17)	0.26942 (13)	0.0445 (5)
Cl4	0.49046 (12)	0.66082 (7)	0.36273 (4)	0.0725 (2)
C22	0.5387 (4)	0.56247 (18)	0.22961 (13)	0.0456 (5)
H22	0.6712	0.5610	0.2534	0.055*
C23	0.4732 (3)	0.51941 (16)	0.15314 (12)	0.0391 (4)
N4	0.6126 (3)	0.47573 (15)	0.11472 (11)	0.0463 (4)
C24	0.5377 (3)	0.43543 (16)	0.04548 (12)	0.0413 (4)
C25	0.6353 (4)	0.37835 (19)	−0.01252 (13)	0.0498 (5)
H25	0.7758	0.3907	−0.0074	0.060*
C26	0.5749 (5)	0.2668 (2)	−0.00338 (16)	0.0633 (7)
H26A	0.6464	0.2209	−0.0319	0.076*
H26B	0.5978	0.2470	0.0529	0.076*
C27	0.3554 (5)	0.2660 (2)	−0.04104 (17)	0.0693 (8)
H27A	0.2791	0.2455	−0.0018	0.083*
H27B	0.3277	0.2197	−0.0866	0.083*
C28	0.3087 (4)	0.3782 (2)	−0.06852 (13)	0.0540 (6)
C29	0.1155 (5)	0.3946 (4)	−0.12606 (19)	0.0893 (12)
H29A	0.0101	0.3769	−0.0999	0.134*
H29B	0.1097	0.3523	−0.1727	0.134*
H29C	0.1037	0.4650	−0.1421	0.134*
C30	0.5031 (4)	0.40956 (18)	−0.09395 (13)	0.0495 (5)
C31	0.5182 (6)	0.5232 (2)	−0.11237 (17)	0.0722 (9)
H31A	0.6463	0.5377	−0.1221	0.108*
H31B	0.4964	0.5627	−0.0673	0.108*
H31C	0.4214	0.5405	−0.1592	0.108*
C32	0.5429 (5)	0.3497 (2)	−0.16611 (15)	0.0638 (7)
H32A	0.4404	0.3628	−0.2121	0.096*
H32B	0.5470	0.2780	−0.1540	0.096*
H32C	0.6662	0.3706	−0.1777	0.096*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0469 (11)	0.0376 (10)	0.0361 (9)	−0.0027 (8)	0.0115 (8)	−0.0006 (7)
N1	0.0440 (10)	0.0562 (11)	0.0383 (8)	−0.0062 (8)	0.0098 (7)	−0.0093 (8)
C2	0.0465 (11)	0.0411 (10)	0.0354 (9)	−0.0067 (9)	0.0142 (8)	−0.0013 (8)
C3	0.0435 (12)	0.0503 (13)	0.0499 (12)	−0.0078 (10)	0.0193 (9)	−0.0088 (10)
C4	0.0569 (13)	0.0377 (10)	0.0449 (11)	−0.0050 (9)	0.0270 (10)	0.0006 (9)
Cl1	0.0768 (4)	0.0686 (4)	0.0686 (4)	−0.0012 (3)	0.0402 (3)	−0.0185 (4)
C5	0.0673 (14)	0.0421 (11)	0.0277 (9)	−0.0043 (10)	0.0141 (9)	0.0011 (8)
Cl2	0.0963 (5)	0.0933 (5)	0.0377 (3)	0.0067 (5)	0.0092 (3)	−0.0173 (3)
C6	0.0516 (13)	0.0508 (13)	0.0364 (10)	0.0011 (10)	0.0028 (9)	0.0022 (9)
C7	0.0448 (11)	0.0364 (10)	0.0349 (9)	0.0002 (8)	0.0119 (8)	0.0046 (8)
N2	0.0438 (10)	0.0466 (10)	0.0364 (8)	0.0065 (8)	0.0076 (7)	−0.0009 (7)
C8	0.0435 (11)	0.0374 (10)	0.0390 (9)	0.0035 (8)	0.0132 (8)	0.0026 (8)
C9	0.0513 (12)	0.0463 (11)	0.0464 (11)	0.0062 (9)	0.0193 (9)	−0.0040 (9)
C10	0.0673 (15)	0.0422 (11)	0.0545 (12)	−0.0003 (10)	0.0304 (11)	−0.0004 (10)
C11	0.0784 (17)	0.0469 (12)	0.0384 (10)	0.0112 (11)	0.0205 (11)	0.0076 (9)
C12	0.0568 (13)	0.0491 (12)	0.0354 (9)	−0.0005 (10)	0.0118 (9)	−0.0071 (9)
C13	0.0713 (19)	0.102 (2)	0.0514 (15)	−0.0163 (17)	0.0087 (13)	−0.0273 (16)
C14	0.0688 (14)	0.0381 (11)	0.0431 (10)	0.0026 (10)	0.0185 (10)	−0.0035 (9)
C15	0.122 (3)	0.0364 (13)	0.0670 (17)	−0.0035 (16)	0.0291 (18)	0.0021 (12)
C16	0.091 (2)	0.0517 (14)	0.0576 (14)	0.0095 (14)	0.0271 (14)	−0.0129 (12)
C17	0.0555 (12)	0.0448 (11)	0.0320 (9)	−0.0028 (10)	0.0094 (8)	−0.0052 (8)
N3	0.0462 (11)	0.0618 (12)	0.0403 (9)	0.0016 (9)	0.0078 (8)	−0.0121 (9)
C18	0.0440 (11)	0.0406 (10)	0.0345 (9)	−0.0013 (8)	0.0088 (8)	−0.0049 (8)
C19	0.0445 (12)	0.0550 (13)	0.0389 (10)	0.0013 (10)	0.0104 (9)	−0.0075 (10)
C20	0.0554 (12)	0.0366 (10)	0.0391 (10)	−0.0022 (9)	0.0174 (9)	−0.0054 (8)
Cl3	0.0682 (4)	0.0729 (4)	0.0587 (4)	0.0040 (3)	0.0257 (3)	−0.0225 (3)
C21	0.0595 (13)	0.0402 (11)	0.0344 (9)	−0.0056 (10)	0.0108 (9)	−0.0050 (8)
Cl4	0.0801 (4)	0.0897 (5)	0.0448 (3)	−0.0031 (4)	0.0059 (3)	−0.0286 (3)
C22	0.0523 (13)	0.0483 (12)	0.0360 (10)	−0.0011 (10)	0.0083 (9)	−0.0055 (9)
C23	0.0496 (12)	0.0366 (10)	0.0316 (9)	−0.0007 (8)	0.0094 (8)	0.0002 (8)
N4	0.0511 (11)	0.0484 (10)	0.0399 (9)	0.0044 (9)	0.0103 (8)	−0.0033 (8)
C24	0.0527 (12)	0.0368 (10)	0.0358 (9)	0.0050 (9)	0.0126 (8)	−0.0002 (8)
C25	0.0638 (15)	0.0473 (12)	0.0420 (10)	0.0069 (11)	0.0194 (10)	−0.0035 (9)
C26	0.098 (2)	0.0417 (12)	0.0532 (13)	0.0098 (13)	0.0226 (13)	0.0012 (10)
C27	0.102 (2)	0.0506 (15)	0.0646 (15)	−0.0217 (15)	0.0385 (15)	−0.0184 (12)
C28	0.0587 (14)	0.0658 (15)	0.0387 (10)	−0.0009 (12)	0.0130 (9)	−0.0165 (10)
C29	0.073 (2)	0.137 (3)	0.0522 (16)	0.011 (2)	−0.0005 (14)	−0.0383 (19)
C30	0.0681 (15)	0.0456 (12)	0.0371 (9)	0.0031 (10)	0.0164 (9)	−0.0024 (8)
C31	0.116 (3)	0.0505 (15)	0.0551 (15)	0.0064 (15)	0.0300 (16)	0.0097 (12)
C32	0.088 (2)	0.0659 (17)	0.0417 (11)	0.0049 (14)	0.0243 (12)	−0.0104 (11)

Geometric parameters (Å, º) top

C1—N1	1.307 (3)	C17—N3	1.297 (3)
C1—C8	1.429 (3)	C17—C24	1.435 (3)
C1—C12	1.500 (3)	C17—C28	1.511 (3)
N1—C2	1.391 (3)	N3—C18	1.395 (3)
C2—C3	1.408 (3)	C18—C19	1.409 (3)
C2—C7	1.403 (3)	C18—C23	1.405 (3)
C3—C4	1.371 (3)	C19—C20	1.373 (3)
C3—H3	0.9300	C19—H19	0.9300
C4—C5	1.392 (3)	C20—C21	1.399 (3)
C4—Cl1	1.726 (2)	C20—Cl3	1.732 (2)
C5—C6	1.372 (3)	C21—C22	1.377 (3)
C5—Cl2	1.730 (2)	C21—Cl4	1.723 (2)
C6—C7	1.413 (3)	C22—C23	1.403 (3)
C6—H6	0.9300	C22—H22	0.9300
C7—N2	1.390 (3)	C23—N4	1.398 (3)
N2—C8	1.299 (3)	N4—C24	1.297 (3)
C8—C9	1.508 (3)	C24—C25	1.503 (3)
C9—C10	1.542 (3)	C25—C26	1.536 (4)
C9—C14	1.556 (3)	C25—C30	1.551 (3)
C9—H9	0.9800	C25—H25	0.9800
C10—C11	1.533 (4)	C26—C27	1.534 (5)
C10—H10A	0.9700	C26—H26A	0.9700
C10—H10B	0.9700	C26—H26B	0.9700
C11—C12	1.552 (3)	C27—C28	1.555 (4)
C11—H11A	0.9700	C27—H27A	0.9700
C11—H11B	0.9700	C27—H27B	0.9700
C12—C13	1.512 (4)	C28—C29	1.510 (4)
C12—C14	1.571 (3)	C28—C30	1.559 (3)
C13—H13A	0.9600	C29—H29A	0.9600
C13—H13B	0.9600	C29—H29B	0.9600
C13—H13C	0.9600	C29—H29C	0.9600
C14—C15	1.516 (4)	C30—C31	1.528 (4)
C14—C16	1.549 (3)	C30—C32	1.525 (3)
C15—H15A	0.9600	C31—H31A	0.9600
C15—H15B	0.9600	C31—H31B	0.9600
C15—H15C	0.9600	C31—H31C	0.9600
C16—H16A	0.9600	C32—H32A	0.9600
C16—H16B	0.9600	C32—H32B	0.9600
C16—H16C	0.9600	C32—H32C	0.9600

N1—C1—C8	124.23 (19)	N3—C17—C24	124.46 (19)
N1—C1—C12	128.5 (2)	N3—C17—C28	128.6 (2)
C8—C1—C12	107.24 (18)	C24—C17—C28	106.85 (19)
C1—N1—C2	113.48 (18)	C17—N3—C18	113.25 (19)
N1—C2—C3	118.2 (2)	N3—C18—C19	118.16 (19)
N1—C2—C7	121.72 (19)	N3—C18—C23	122.47 (18)
C3—C2—C7	120.05 (19)	C19—C18—C23	119.35 (19)
C4—C3—C2	119.3 (2)	C20—C19—C18	119.8 (2)
C4—C3—H3	120.3	C20—C19—H19	120.1
C2—C3—H3	120.3	C18—C19—H19	120.1
C3—C4—C5	120.9 (2)	C19—C20—C21	120.8 (2)
C3—C4—Cl1	119.35 (19)	C19—C20—Cl3	119.33 (18)
C5—C4—Cl1	119.72 (18)	C21—C20—Cl3	119.89 (17)
C6—C5—C4	120.8 (2)	C22—C21—C20	120.2 (2)
C6—C5—Cl2	118.45 (19)	C22—C21—Cl4	119.14 (18)
C4—C5—Cl2	120.74 (18)	C20—C21—Cl4	120.62 (17)
C5—C6—C7	119.6 (2)	C21—C22—C23	119.9 (2)
C5—C6—H6	120.2	C21—C22—H22	120.1
C7—C6—H6	120.2	C23—C22—H22	120.1
N2—C7—C6	117.5 (2)	N4—C23—C22	117.9 (2)
N2—C7—C2	123.25 (19)	N4—C23—C18	122.15 (18)
C6—C7—C2	119.2 (2)	C22—C23—C18	119.9 (2)
C8—N2—C7	113.00 (19)	C24—N4—C23	113.4 (2)
N2—C8—C1	124.31 (19)	N4—C24—C17	124.2 (2)
N2—C8—C9	129.3 (2)	N4—C24—C25	129.9 (2)
C1—C8—C9	106.22 (18)	C17—C24—C25	105.84 (19)
C8—C9—C10	104.05 (18)	C24—C25—C26	103.69 (19)
C8—C9—C14	99.52 (18)	C24—C25—C30	100.70 (19)
C10—C9—C14	102.10 (19)	C26—C25—C30	102.4 (2)
C8—C9—H9	116.3	C24—C25—H25	116.0
C10—C9—H9	116.3	C26—C25—H25	116.0
C14—C9—H9	116.3	C30—C25—H25	116.0
C9—C10—C11	104.06 (19)	C27—C26—C25	103.6 (2)
C9—C10—H10A	110.9	C27—C26—H26A	111.0
C11—C10—H10A	110.9	C25—C26—H26A	111.0
C9—C10—H10B	110.9	C27—C26—H26B	111.0
C11—C10—H10B	110.9	C25—C26—H26B	111.0
H10A—C10—H10B	109.0	H26A—C26—H26B	109.0
C10—C11—C12	104.48 (18)	C26—C27—C28	104.4 (2)
C10—C11—H11A	110.9	C26—C27—H27A	110.9
C12—C11—H11A	110.9	C28—C27—H27A	110.9
C10—C11—H11B	110.9	C26—C27—H27B	110.9
C12—C11—H11B	110.9	C28—C27—H27B	110.9
H11A—C11—H11B	108.9	H27A—C27—H27B	108.9
C1—C12—C13	115.7 (2)	C29—C28—C17	115.0 (2)
C1—C12—C11	102.89 (18)	C29—C28—C30	119.7 (2)
C13—C12—C11	115.9 (2)	C17—C28—C30	99.48 (19)
C1—C12—C14	99.56 (18)	C29—C28—C27	115.7 (3)
C13—C12—C14	119.1 (2)	C17—C28—C27	103.3 (2)
C11—C12—C14	101.02 (19)	C30—C28—C27	100.9 (2)
C12—C13—H13A	109.5	C28—C29—H29A	109.5
C12—C13—H13B	109.5	C28—C29—H29B	109.5
H13A—C13—H13B	109.5	H29A—C29—H29B	109.5
C12—C13—H13C	109.5	C28—C29—H29C	109.5
H13A—C13—H13C	109.5	H29A—C29—H29C	109.5
H13B—C13—H13C	109.5	H29B—C29—H29C	109.5
C15—C14—C16	108.1 (2)	C31—C30—C32	107.8 (2)
C15—C14—C9	113.9 (2)	C31—C30—C25	112.7 (2)
C16—C14—C9	113.3 (2)	C32—C30—C25	114.0 (2)
C15—C14—C12	113.9 (2)	C31—C30—C28	114.4 (2)
C16—C14—C12	112.9 (2)	C32—C30—C28	113.4 (2)
C9—C14—C12	94.46 (17)	C25—C30—C28	94.44 (18)
C14—C15—H15A	109.5	C30—C31—H31A	109.5
C14—C15—H15B	109.5	C30—C31—H31B	109.5
H15A—C15—H15B	109.5	H31A—C31—H31B	109.5
C14—C15—H15C	109.5	C30—C31—H31C	109.5
H15A—C15—H15C	109.5	H31A—C31—H31C	109.5
H15B—C15—H15C	109.5	H31B—C31—H31C	109.5
C14—C16—H16A	109.5	C30—C32—H32A	109.5
C14—C16—H16B	109.5	C30—C32—H32B	109.5
H16A—C16—H16B	109.5	H32A—C32—H32B	109.5
C14—C16—H16C	109.5	C30—C32—H32C	109.5
H16A—C16—H16C	109.5	H32A—C32—H32C	109.5
H16B—C16—H16C	109.5	H32B—C32—H32C	109.5

Experimental details

Crystal data
Chemical formula	C₁₆H₁₆Cl₂N₂
M_r	307.21
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	293
a, b, c (Å)	6.9741 (3), 13.0892 (5), 16.9594 (5)
β (°)	101.701 (3)
V (Å³)	1515.97 (10)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.42
Crystal size (mm)	0.32 × 0.18 × 0.11

Data collection
Diffractometer	Oxford Xcalibur Sapphire3
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)
T_min, T_max	0.897, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	42674, 12344, 7343
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.806

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.058, 0.163, 0.93
No. of reflections	12344
No. of parameters	367
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.18
Absolute structure	Flack (1983), with 5825 Friedel pairs
Absolute structure parameter	0.03 (5)

Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), Mercury (Macrae et al., 2008) and PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008).

Acknowledgements

This research was funded by a CCSU-AAUP research grant.

References

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