Bis[1,3-bis­(1H-benzimidazol-2-yl)benzene-κN³](succinato-κ²O,O′)zinc(II), a succinate-chelated monomeric compound

The succinate dianion in the title 1:2 zinc succinate–1,3-bis­(benzimidazol-2-yl)benzene adduct, [Zn(C₄H₄O₄)(C₂₀H₁₄N₄)₂], chelates the Zn atom, which is datively bonded to two of the N-heterocycles in a tetra­hedral geometry. The Zn atom and the succinate dianion lie on a twofold rotation axis. The amino –NH group of one heterocycle forms a weak intra­molecular hydrogen bond to the carbonyl O atom; that of the second heterocycle engages in an inter­molecular N—H...N inter­action resulting in a linear chain structure.

Key indicators

• Single-crystal X-ray study
• T = 291 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.035
• wR factor = 0.103
• Data-to-parameter ratio = 15.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C21    -   C22     ..       6.81 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C21

Alert level G
PLAT794_ALERT_5_G Check Predicted Bond Valency for Zn1         (2)       1.95
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          2

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The reaction between 1,3-bis(benzimidazol-2-ylmethyl)benzene and zinc terephthalate affords the expected 1:1 adduct as a methanol solvate. The compound adopts a layer structure owing to bridging by both the N-heterocycle and the terephthalate dianion (Meng et al., 2007). The succinate dianion is not rigid like the terephthalate dianion. It typically lies on a center-of-inversion in most metal succinates (CSD Version 5.28, May 2007) and functions as a bridging dianion; however, the succinate group chelates to the zinc atom in the zinc succinate adduct of this heterocycle. Both the cation and the dianion lie on a twofold rotation axis in the monomeric compound (Scheme I, Fig. 1).

Chelation by a succinate group has been documented in only three cases: the polymeric hexaaquatricobalt(III) (Forster et al., 2004) and monomeric tetraaquanickel(II) (Gupta & Devi, 1978) derivatives, and the salt, diaquabis(phenanthrolinato)manganese(II) bis(phenanthroline)succinatomanganate(II) succinate heptahydrate (Zheng, Lin & Sun, 2001). The title compound has the metal center connected to two N-heterocycles; expansion of the coordination number is precluded as the second tertiary N-donor site of both ligands is already engaged in hydrogen bonding interactions. This possibly forces the succinate group to bind in the uncommon chelating mode. The amino –NH group of one heterocycle in hydrogen-bonded to the carbonyl oxygen atom [3.158 (2) Å]; that of the second heterocycle engages in an intermolecular N–H···N interaction [2.839 (2) Å] to furnish a linear chain motif.

The zinc-oxygen bond distance is similar to that found in zinc succinate itself; the metal center in this compound shows tetrahedral coordination and the anion behaves as a bridging group to result in the formation of a polymeric network motif (Bowden et al., 2003; Zheng, Peters & von Schnering, 2001). The distance is, however, shorter than those found in other higher-than-four-coordinateamine adducts (Tao et al., 2001; Yin et al., 2002; Ying et al., 2003; Zeng et al., 2007; Zheng, 2004; Zheng et al., 2002; Zhou et al., 2005).

Related literature

For the structure of the adduct the N-heterocycle with zinc terephthalate, see Meng et al. (2007). For the rare examples of chelation by a succinate group, see Forster et al. (2004); Gupta & Devi (1978); Zheng, Lin & Sun (2001). For the structure of zinc succinate, see Bowden et al. (2003); Zheng, Peters & von Schnering (2001). For higher-than-four-coordinate amine adducts of zinc succinate, see Tao et al. (2001); Yin et al. (2002); Ying et al. (2003); Zeng et al. (2007); Zheng (2004); Zheng et al. (2002); Zhou et al. (2005). For the synthesis of the N-heterocycle, see Chawla & Gill (1997).

S2. Experimental

The N-heterocycle was prepared according to a reported procedure (Chawla & Gill, 1997). Zinc nitrate hexahydrate (0.074 g, 0.25 mmol), succinic acid (0.0148 g, 0.125 mmol),1, 3-bis(benzimidazol-2-ylmethyl)benzene (0.039 g, 0.125 mmol), ethanol (2 ml) and water (15 ml) were placed in a 23 -ml, Teflon-lined, stainless-steel Parr bomb. (Neither sodium hydroxide nor postassium hydroxide was added.) The bomb was heated at 433 K for 5 days and cooled to room temperature at 5 K h^-1. Brown block-shaped crystals picked out by hand (in 10% yield).

S3. Refinement

The amino H-atoms were located in a difference Fourier map, and were refined with a distance restraint of 0.85 (1) Å; their temperature factors were freely refined. The carbon-bound H-atoms were generated geometrically (C–H 0.93 to 0.97 Å); they were included in the refinement in the riding model approximation, with U(H) set to 1.2U_eq(C).

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2007).

Figures

Fig. 1. Thermal ellipsoid plot depicting the coordination geometry of zinc; displacement ellipsoids are drawn at the 50% probability level, and H atoms as spheres of arbitrary radius. [Symmery code (i): 1 – x, y, 3/2 – z.]

Bis[1,3-bis(1H-benzimidazol-2-yl)benzene-κN³](succinato-\k²O,O')zinc(II)

Crystal data

[Zn(C4H4O4)(C20H14N4)2]	F(000) = 1656
Mr = 802.15	Dx = 1.458 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 4938 reflections
a = 21.453 (2) Å	θ = 2.3–25.0°
b = 10.272 (1) Å	µ = 0.73 mm^−1
c = 17.587 (2) Å	T = 291 K
β = 109.411 (1)°	Block, brown
V = 3655.2 (6) Å^3	0.46 × 0.34 × 0.22 mm
Z = 4

Data collection

Bruker APEXII area-detector diffractometer	4186 independent reflections
Radiation source: fine-focus sealed tube	3354 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.034
φ and ω scans	θmax = 27.5°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −27→27
Tmin = 0.687, Tmax = 0.856	k = −13→13
14308 measured reflections	l = −22→22

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.103	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0519P)^2 + 1.7754P] where P = (Fo^2 + 2Fc^2)/3
4186 reflections	(Δ/σ)max = 0.001
266 parameters	Δρmax = 0.41 e Å^−3
2 restraints	Δρmin = −0.24 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zn1	0.5000	0.19880 (3)	0.7500	0.04623 (12)
O1	0.53016 (8)	0.09147 (13)	0.67838 (9)	0.0592 (4)
O2	0.56800 (11)	−0.08025 (16)	0.63523 (13)	0.0907 (6)
N1	0.42681 (7)	0.32303 (14)	0.69164 (9)	0.0425 (3)
N2	0.38107 (8)	0.50277 (17)	0.62655 (10)	0.0507 (4)
H2n	0.3757 (12)	0.5670 (17)	0.5949 (12)	0.072 (8)*
N3	0.59125 (9)	0.13643 (17)	0.53998 (11)	0.0522 (4)
H3n	0.5727 (11)	0.103 (2)	0.5708 (13)	0.074 (8)*
N4	0.63664 (8)	0.28509 (16)	0.48210 (10)	0.0512 (4)
C1	0.36481 (9)	0.33981 (19)	0.70053 (11)	0.0440 (4)
C2	0.33136 (10)	0.2633 (2)	0.74022 (13)	0.0553 (5)
H2	0.3501	0.1882	0.7680	0.066*
C3	0.26909 (12)	0.3049 (3)	0.73619 (15)	0.0675 (6)
H3	0.2454	0.2565	0.7620	0.081*
C4	0.24068 (11)	0.4171 (3)	0.69462 (15)	0.0727 (7)
H4	0.1986	0.4415	0.6935	0.087*
C5	0.27305 (11)	0.4924 (3)	0.65541 (15)	0.0651 (6)
H5	0.2539	0.5670	0.6274	0.078*
C6	0.33596 (10)	0.4519 (2)	0.65957 (12)	0.0494 (4)
C7	0.43377 (9)	0.42315 (17)	0.64697 (11)	0.0428 (4)
C8	0.49252 (9)	0.44713 (18)	0.62339 (11)	0.0440 (4)
C9	0.51755 (9)	0.34797 (18)	0.58804 (11)	0.0440 (4)
H9	0.4968	0.2672	0.5787	0.053*
C10	0.57367 (9)	0.36922 (19)	0.56657 (11)	0.0453 (4)
C11	0.60443 (10)	0.4902 (2)	0.58136 (13)	0.0530 (5)
H11	0.6423	0.5046	0.5680	0.064*
C12	0.57930 (11)	0.5891 (2)	0.61573 (13)	0.0578 (5)
H12	0.6001	0.6698	0.6251	0.069*
C13	0.52322 (10)	0.56822 (19)	0.63630 (12)	0.0517 (5)
H13	0.5060	0.6353	0.6588	0.062*
C14	0.60041 (9)	0.2648 (2)	0.52894 (11)	0.0464 (4)
C15	0.62476 (10)	0.0671 (2)	0.49841 (12)	0.0523 (5)
C16	0.63407 (12)	−0.0656 (2)	0.49111 (15)	0.0683 (6)
H16	0.6147	−0.1273	0.5148	0.082*
C17	0.67363 (13)	−0.1007 (3)	0.44680 (16)	0.0766 (7)
H17	0.6812	−0.1886	0.4405	0.092*
C18	0.70266 (12)	−0.0080 (3)	0.41107 (16)	0.0782 (8)
H18	0.7290	−0.0358	0.3816	0.094*
C19	0.69331 (11)	0.1232 (3)	0.41826 (15)	0.0682 (6)
H19	0.7127	0.1844	0.3942	0.082*
C20	0.65334 (10)	0.1610 (2)	0.46324 (12)	0.0520 (5)
C21	0.54524 (11)	−0.02897 (19)	0.68279 (14)	0.0541 (5)
C22	0.53548 (11)	−0.1074 (2)	0.75113 (15)	0.0629 (6)
H22A	0.5632	−0.0715	0.8022	0.075*
H22B	0.5495	−0.1965	0.7479	0.075*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.0571 (2)	0.03012 (16)	0.0570 (2)	0.000	0.02633 (15)	0.000
O1	0.0847 (10)	0.0345 (7)	0.0713 (10)	0.0041 (7)	0.0431 (8)	0.0002 (6)
O2	0.1373 (17)	0.0521 (9)	0.1215 (16)	0.0084 (10)	0.0953 (15)	−0.0045 (10)
N1	0.0465 (8)	0.0398 (8)	0.0440 (8)	−0.0014 (6)	0.0189 (7)	−0.0029 (6)
N2	0.0524 (9)	0.0507 (10)	0.0522 (10)	0.0089 (8)	0.0216 (8)	0.0085 (8)
N3	0.0616 (10)	0.0489 (10)	0.0520 (10)	−0.0035 (8)	0.0267 (8)	−0.0015 (8)
N4	0.0473 (9)	0.0584 (10)	0.0526 (10)	0.0051 (7)	0.0229 (7)	0.0056 (8)
C1	0.0455 (10)	0.0478 (10)	0.0410 (10)	−0.0036 (8)	0.0176 (8)	−0.0075 (8)
C2	0.0577 (12)	0.0611 (12)	0.0519 (12)	−0.0071 (10)	0.0247 (10)	−0.0024 (10)
C3	0.0583 (13)	0.0902 (18)	0.0639 (14)	−0.0106 (12)	0.0335 (11)	−0.0048 (12)
C4	0.0502 (12)	0.101 (2)	0.0736 (16)	0.0080 (13)	0.0293 (11)	−0.0012 (14)
C5	0.0545 (12)	0.0783 (16)	0.0647 (14)	0.0146 (11)	0.0227 (11)	0.0048 (12)
C6	0.0501 (10)	0.0562 (11)	0.0440 (11)	0.0029 (9)	0.0183 (8)	−0.0036 (9)
C7	0.0469 (10)	0.0404 (9)	0.0427 (10)	0.0007 (7)	0.0171 (8)	−0.0021 (7)
C8	0.0476 (10)	0.0435 (9)	0.0422 (10)	0.0011 (8)	0.0165 (8)	0.0040 (8)
C9	0.0480 (10)	0.0406 (9)	0.0457 (10)	−0.0011 (8)	0.0187 (8)	0.0020 (8)
C10	0.0460 (10)	0.0477 (10)	0.0435 (10)	0.0017 (8)	0.0168 (8)	0.0050 (8)
C11	0.0501 (11)	0.0536 (11)	0.0595 (13)	−0.0060 (9)	0.0240 (9)	0.0037 (9)
C12	0.0638 (13)	0.0445 (11)	0.0680 (14)	−0.0121 (9)	0.0257 (11)	−0.0024 (10)
C13	0.0600 (12)	0.0428 (10)	0.0554 (12)	0.0005 (9)	0.0234 (9)	−0.0026 (9)
C14	0.0460 (10)	0.0497 (10)	0.0445 (10)	0.0013 (8)	0.0165 (8)	0.0042 (8)
C15	0.0547 (11)	0.0551 (12)	0.0445 (11)	0.0024 (9)	0.0132 (9)	−0.0076 (9)
C16	0.0784 (15)	0.0582 (13)	0.0654 (15)	−0.0043 (11)	0.0200 (12)	−0.0161 (11)
C17	0.0726 (16)	0.0720 (16)	0.0787 (17)	0.0062 (13)	0.0165 (13)	−0.0310 (14)
C18	0.0580 (14)	0.101 (2)	0.0755 (17)	0.0090 (13)	0.0218 (12)	−0.0330 (15)
C19	0.0555 (13)	0.0870 (17)	0.0666 (15)	0.0038 (12)	0.0261 (11)	−0.0113 (13)
C20	0.0434 (10)	0.0651 (12)	0.0458 (11)	0.0061 (9)	0.0128 (8)	−0.0026 (9)
C21	0.0615 (12)	0.0404 (10)	0.0692 (14)	−0.0018 (9)	0.0334 (11)	−0.0061 (9)
C22	0.0720 (14)	0.0428 (11)	0.0751 (15)	0.0132 (10)	0.0261 (12)	0.0016 (10)

Geometric parameters (Å, º)

Zn1—O1^i	1.940 (1)	C7—C8	1.473 (2)
Zn1—O1	1.940 (1)	C8—C9	1.391 (3)
Zn1—N1^i	2.019 (2)	C8—C13	1.390 (3)
Zn1—N1	2.019 (2)	C9—C10	1.394 (3)
O1—C21	1.275 (2)	C9—H9	0.9300
O2—C21	1.219 (2)	C10—C11	1.390 (3)
N1—C7	1.332 (2)	C10—C14	1.473 (3)
N1—C1	1.401 (2)	C11—C12	1.380 (3)
N2—C7	1.344 (2)	C11—H11	0.9300
N2—C6	1.386 (3)	C12—C13	1.383 (3)
N2—H2N	0.846 (10)	C12—H12	0.9300
N3—C14	1.357 (3)	C13—H13	0.9300
N3—C15	1.381 (3)	C15—C16	1.390 (3)
N3—H3N	0.846 (10)	C15—C20	1.393 (3)
N4—C14	1.324 (2)	C16—C17	1.377 (3)
N4—C20	1.394 (3)	C16—H16	0.9300
C1—C6	1.390 (3)	C17—C18	1.396 (4)
C1—C2	1.397 (3)	C17—H17	0.9300
C2—C3	1.382 (3)	C18—C19	1.375 (4)
C2—H2	0.9300	C18—H18	0.9300
C3—C4	1.392 (4)	C19—C20	1.401 (3)
C3—H3	0.9300	C19—H19	0.9300
C4—C5	1.369 (3)	C21—C22	1.518 (3)
C4—H4	0.9300	C22—C22^i	1.509 (4)
C5—C6	1.391 (3)	C22—H22A	0.9700
C5—H5	0.9300	C22—H22B	0.9700
O1^i—Zn1—O1	110.7 (1)	C10—C9—H9	119.9
O1—Zn1—N1	113.6 (1)	C11—C10—C9	119.24 (18)
O1—Zn1—N1^i	108.6 (1)	C11—C10—C14	120.22 (17)
O1^i—Zn1—N1	108.6 (1)	C9—C10—C14	120.54 (17)
O1^i—Zn1—N1^i	113.6 (1)	C12—C11—C10	120.65 (18)
N1^i—Zn1—N1	101.6 (1)	C12—C11—H11	119.7
C21—O1—Zn1	130.16 (14)	C10—C11—H11	119.7
C7—N1—C1	105.51 (15)	C13—C12—C11	120.04 (19)
C7—N1—Zn1	124.55 (12)	C13—C12—H12	120.0
C1—N1—Zn1	128.90 (12)	C11—C12—H12	120.0
C7—N2—C6	107.51 (16)	C12—C13—C8	120.13 (18)
C7—N2—H2n	124.7 (17)	C12—C13—H13	119.9
C6—N2—H2n	127.5 (17)	C8—C13—H13	119.9
C14—N3—C15	107.46 (17)	N4—C14—N3	112.65 (18)
C14—N3—H3n	127.5 (18)	N4—C14—C10	124.18 (18)
C15—N3—H3n	124.7 (18)	N3—C14—C10	123.16 (17)
C14—N4—C20	104.75 (17)	N3—C15—C16	132.1 (2)
C6—C1—N1	108.65 (16)	N3—C15—C20	105.13 (17)
C6—C1—C2	120.71 (18)	C16—C15—C20	122.7 (2)
N1—C1—C2	130.62 (18)	C15—C16—C17	116.3 (2)
C3—C2—C1	116.7 (2)	C15—C16—H16	121.8
C3—C2—H2	121.7	C17—C16—H16	121.8
C1—C2—H2	121.7	C16—C17—C18	121.8 (2)
C2—C3—C4	122.0 (2)	C16—C17—H17	119.1
C2—C3—H3	119.0	C18—C17—H17	119.1
C4—C3—H3	119.0	C19—C18—C17	121.8 (2)
C5—C4—C3	121.7 (2)	C19—C18—H18	119.1
C5—C4—H4	119.1	C17—C18—H18	119.1
C3—C4—H4	119.1	C18—C19—C20	117.3 (3)
C4—C5—C6	116.8 (2)	C18—C19—H19	121.3
C4—C5—H5	121.6	C20—C19—H19	121.3
C6—C5—H5	121.6	N4—C20—C19	129.9 (2)
N2—C6—C1	106.09 (16)	N4—C20—C15	109.99 (17)
N2—C6—C5	131.7 (2)	C19—C20—C15	120.1 (2)
C1—C6—C5	122.2 (2)	O2—C21—O1	121.9 (2)
N1—C7—N2	112.23 (16)	O2—C21—C22	120.37 (19)
N1—C7—C8	124.70 (16)	O1—C21—C22	117.68 (17)
N2—C7—C8	123.06 (17)	C21—C22—C22^i	112.5 (2)
C9—C8—C13	119.72 (17)	C21—C22—H22A	109.1
C9—C8—C7	119.80 (16)	C22^i—C22—H22A	109.1
C13—C8—C7	120.47 (17)	C21—C22—H22B	109.1
C8—C9—C10	120.20 (17)	C22^i—C22—H22B	109.1
C8—C9—H9	119.9	H22A—C22—H22B	107.8
O1^i—Zn1—O1—C21	−16.11 (17)	C7—C8—C9—C10	−179.10 (17)
N1^i—Zn1—O1—C21	109.22 (19)	C8—C9—C10—C11	0.4 (3)
N1—Zn1—O1—C21	−138.57 (19)	C8—C9—C10—C14	−179.86 (17)
O1^i—Zn1—N1—C7	169.60 (14)	C9—C10—C11—C12	−1.0 (3)
O1—Zn1—N1—C7	−66.76 (15)	C14—C10—C11—C12	179.24 (19)
N1^i—Zn1—N1—C7	49.62 (13)	C10—C11—C12—C13	0.4 (3)
O1^i—Zn1—N1—C1	2.97 (17)	C11—C12—C13—C8	0.8 (3)
O1—Zn1—N1—C1	126.61 (15)	C9—C8—C13—C12	−1.5 (3)
N1^i—Zn1—N1—C1	−117.01 (16)	C7—C8—C13—C12	178.48 (19)
C7—N1—C1—C6	0.3 (2)	C20—N4—C14—N3	−1.5 (2)
Zn1—N1—C1—C6	168.86 (13)	C20—N4—C14—C10	177.43 (17)
C7—N1—C1—C2	178.8 (2)	C15—N3—C14—N4	1.0 (2)
Zn1—N1—C1—C2	−12.6 (3)	C15—N3—C14—C10	−177.96 (17)
C6—C1—C2—C3	0.1 (3)	C11—C10—C14—N4	−25.1 (3)
N1—C1—C2—C3	−178.3 (2)	C9—C10—C14—N4	155.19 (19)
C1—C2—C3—C4	0.1 (3)	C11—C10—C14—N3	153.8 (2)
C2—C3—C4—C5	0.0 (4)	C9—C10—C14—N3	−26.0 (3)
C3—C4—C5—C6	−0.4 (4)	C14—N3—C15—C16	177.5 (2)
C7—N2—C6—C1	0.4 (2)	C14—N3—C15—C20	0.0 (2)
C7—N2—C6—C5	−177.9 (2)	N3—C15—C16—C17	−177.0 (2)
N1—C1—C6—N2	−0.4 (2)	C20—C15—C16—C17	0.1 (3)
C2—C1—C6—N2	−179.12 (18)	C15—C16—C17—C18	−0.1 (4)
N1—C1—C6—C5	178.12 (19)	C16—C17—C18—C19	0.0 (4)
C2—C1—C6—C5	−0.6 (3)	C17—C18—C19—C20	0.1 (4)
C4—C5—C6—N2	178.8 (2)	C14—N4—C20—C19	−177.1 (2)
C4—C5—C6—C1	0.7 (3)	C14—N4—C20—C15	1.5 (2)
C1—N1—C7—N2	0.0 (2)	C18—C19—C20—N4	178.3 (2)
Zn1—N1—C7—N2	−169.24 (13)	C18—C19—C20—C15	−0.1 (3)
C1—N1—C7—C8	178.83 (17)	N3—C15—C20—N4	−0.9 (2)
Zn1—N1—C7—C8	9.6 (3)	C16—C15—C20—N4	−178.69 (19)
C6—N2—C7—N1	−0.3 (2)	N3—C15—C20—C19	177.84 (19)
C6—N2—C7—C8	−179.10 (17)	C16—C15—C20—C19	0.0 (3)
N1—C7—C8—C9	51.0 (3)	Zn1—O1—C21—O2	−174.73 (18)
N2—C7—C8—C9	−130.3 (2)	Zn1—O1—C21—C22	3.8 (3)
N1—C7—C8—C13	−129.0 (2)	O2—C21—C22—C22^i	−121.7 (2)
N2—C7—C8—C13	49.7 (3)	O1—C21—C22—C22^i	59.7 (3)
C13—C8—C9—C10	0.8 (3)

Symmetry code: (i) −x+1, y, −z+3/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2n···N4^ii	0.85 (1)	1.99 (1)	2.839 (2)	178 (2)
N3—H3n···O1	0.85 (1)	2.36 (1)	3.158 (2)	158 (2)

Symmetry code: (ii) −x+1, −y+1, −z+1.