catena-Poly[{μ3-3,3′-[(1,7-dioxa-4,10-di­aza­cyclo­dodecane-4,10-di­yl)bis­(methyl­ene)]dibenzoato}cobalt(II)]

Liao, L.; Ingram, C.W.; Bacsa, J.; Parker, C.

doi:10.1107/S1600536813032832

metal-organic compounds

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Volume 70| Part 1| January 2014| Page m24

https://doi.org/10.1107/S1600536813032832

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catena-Poly[{μ₃-3,3′-[(1,7-dioxa-4,10-diazacyclododecane-4,10-diyl)bis(methylene)]dibenzoato}cobalt(II)]

Liang Liao,^a Conrad W. Ingram,^a ^* John Bacsa ^b and Cass Parker ^a

^aCenter for Functional Nanoscale Materials, Department of Chemistry, Clark Atlanta University, 223 James P. Brawley Drive, Atlanta, GA 30314, USA, and ^bX-ray Crystallography Center, Emory University, Atlanta, GA 30322, USA
^*Correspondence e-mail: cingram@cau.edu

(Received 26 September 2013; accepted 3 December 2013; online 18 December 2013)

The title compound, [Co(C₂₄H₂₈N₂O₆)]_n, crystallizes as infinite chains related to one another by inversion centers, giving a centrosymmetric coordination polymer. The Co^II ion, situated on a twofold rotation axis, forms a complex with the crown-4 moiety of the 3,3′-[(1,7-dioxa-4,10-diazacyclododecane-4,10-diyl)bis(methylene)]dibenzoate anion. The distorted octahedral coordination sphere of the Co^II ion is completed by two carboxylate O atoms from two bridging intra-chain ligands. Metallomacrocyclic rings of 16 atoms are present, with each ring containing two Co^II ions and 14 atoms from the bridging ligands. These units repeat as infinite zigzag chains along [101].

CCDC reference: 975042

Related literature

For the structures of coordination polymers (CPs) or compounds with metal-organic frameworks including one-dimensional CPs or MOFs, see: Du et al. (2013 ); Ingram et al. (2012 , 2013 ); Janiak (2013 ); Leong & Vittal (2011 ).

Experimental

Crystal data

[Co(C₂₄H₂₈N₂O₆)]
M_r = 499.41
Monoclinic, C 2/c
a = 20.626 (2) Å
b = 8.9778 (10) Å
c = 13.9263 (16) Å
β = 127.051 (1)°
V = 2058.2 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.88 mm⁻¹
T = 173 K
0.40 × 0.14 × 0.14 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2012) T_min = 0.606, T_max = 0.746
3614 measured reflections
2930 independent reflections
2290 reflections with I > 2σ(I)
R_int = 0.018

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.125
S = 1.02
2930 reflections
150 parameters
H-atom parameters constrained
Δρ_max = 0.80 e Å⁻³
Δρ_min = −0.47 e Å⁻³

Data collection: APEX2 (Bruker, 2011 ); cell refinement: SAINT (Bruker, 2009 ); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009 ); software used to prepare material for publication: OLEX2.

Supporting information

CCDC reference: 975042

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S1600536813032832/gg2131sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536813032832/gg2131Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536813032832/gg2131Isup3.cdx

checkCIF report

Comment top

The title compound is the one of a series of coordination polymers prepared from the anionic ligand LH2, 3,3'-((1,7-dioxa-4,10-diazacyclododecane-4,10-diyl)bis(methylene))dibenzoate. This ligand shows unusual adaptability in that it displays two complexation modes on binding to metals. The ligand attaches to the metal via two oxygen and two nitrogen atoms (forming a crown complex). The crown forms four bonds to the metal, while an ideal coordination number for a Co^II ion is 6. Thus vacant coordination sites suitable for coordination by the carboxylate groups exist. The carboxylate ions behave as monodentate bridging ligands and the entire ligand is hexadentate. The Co^II atom is moved out of the best plane of the crown since this arrangement is better for forming optimal bonds to the ligand. This new compound is novel in that, although the ligands bridge the metal atoms forming one-dimensional chains, the metal atoms are positioned in the center of the organic linker. Topologically, the Co^II atoms and the ligands forms nodes in the network rather than the metal atoms only.

The title compound is synthesized from the ligand LH2, 3,3'-((1,7-dioxa-4,10-diazacyclododecane-4,10-diyl)bis(methylene)) dibenzoic acid. The metal atoms are positioned in the center of the organic linker. The asymmetric unit of the compound contains a Co^II ion and a deprotonated ligand L with formula C₂₄H₂₈N₂O₆Co. The Co^II ion is 6-coordinate in a distorted octahedral geometry being bound to two N atoms and two O atoms of the crown (1,7-diaza-12-crown-4) and two carboxylic O atoms, one from each of two additional intra-chain ligands (Figure 1s). The Co1—O1, Co1—O3 and Co1—N1 bond lengths are 1.9886 (16), 2.2399 (16) and 2.2213 (17) Å, respectively. The O1—Co1—O1 angle is 104.15 (9)°. The shortest distance between two neighboring Co^II ions along a chain is 9.046 (1) Å. The Co^II ion of the Co(crown-4)2+ unit is located on a 2-fold rotation axis. The symmetry independent atoms consist of one half of the ligand with the rotation axis generating the second half of the ligand at the Co atom. Bond circuits consisting of sixteen-membered metallomacrocycle rings can be identified in the structure. Each ring contains two Co^II ions and fourteen non-H atoms of the ligand. Each Co^II ion is a node for three ligands and two connected macrocycle rings. The pair of benzene moieties within a metallomacrocycle ring are remarkably co-planar (the two rings are in the same plane within experimental error). The dihedral angle between this plane and the plane of the next two nearest phenyl rings along the 1-D chain is 68.79 (5)°. Repetition of these units creates a 1-D polymer network with an infinite number of these rings.

Related literature top

For the structures of coordination polymers (CPs) or compounds with metal-organic frameworks including one-dimensional CPs or MOFs, see: Du et al. (2013); Ingram et al. (2012, 2013); Janiak (2013); Leong & Vittal (2011).

Experimental top

The title compound was synthesized in an autoclave by mixing the ligand, 3,3'-((1,7-dioxa-4,10-diazacyclododecane-4,10-diyl)bis(methylene))dibenzoic acid, LH₂ (4x10^-5 mol), (Ingram et al. (2012), (2013)) Co(NO₃)₂·6H₂O (1.2x10^-4 mol, 35.8 mg), H₂O (12 ml) and pyridine (4x10^-2 ml). The mixture was heated at 130 °C in an autoclave for 7 days and then cooled to ambient temperature. Red crystals were collected and washed with H₂O by filtration. Elem. anal. calcd. C₂₄H₂₈N₂O₆Co %: C, 57.72; H, 5.65; N, 5.61; Found: C, 57.79; H, 5.74; N, 5.46.

Structure description top

For the structures of coordination polymers (CPs) or compounds with metal-organic frameworks including one-dimensional CPs or MOFs, see: Du et al. (2013); Ingram et al. (2012, 2013); Janiak (2013); Leong & Vittal (2011).

Computing details top

Data collection: APEX2 (Bruker, 2011); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top

Fig. 1. A view of a portion of one of the chains of (I). Non-H atoms are represented by ellipsoids at the 50% probability level. Sixteen membered metallomacrocycle rings can be identified from this figure.

catena-Poly[{µ₃-3,3'-[(1,7-dioxa-4,10-diazacyclododecane-4,10-diyl)bis(methylene)]dibenzoato}cobalt(II)] top

Crystal data top

[Co(C₂₄H₂₈N₂O₆)]	F(000) = 1044
M_r = 499.41	D_x = 1.612 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 20.626 (2) Å	Cell parameters from 4901 reflections
b = 8.9778 (10) Å	θ = 2.5–31.0°
c = 13.9263 (16) Å	µ = 0.88 mm⁻¹
β = 127.051 (1)°	T = 173 K
V = 2058.2 (4) Å³	Needle, red
Z = 4	0.40 × 0.14 × 0.14 mm

Data collection top

Bruker D8 diffractometer with a APEXII detector	2930 independent reflections
Radiation source: fine-focus sealed tube	2290 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.018
Detector resolution: 512 pixels mm^-1	θ_max = 31.2°, θ_min = 2.6°
φ and ω scans with a narrow frame width	h = −28→18
Absorption correction: multi-scan (SADABS; Bruker, 2012)	k = −12→4
T_min = 0.606, T_max = 0.746	l = −20→19
3614 measured reflections

Refinement top

Refinement on F²	Primary atom site location: iterative
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.049	Hydrogen site location: difference Fourier map
wR(F²) = 0.125	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.073P)²] where P = (F_o² + 2F_c²)/3
2930 reflections	(Δ/σ)_max < 0.001
150 parameters	Δρ_max = 0.80 e Å⁻³
0 restraints	Δρ_min = −0.47 e Å⁻³

Crystal data top

[Co(C₂₄H₂₈N₂O₆)]	V = 2058.2 (4) Å³
M_r = 499.41	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 20.626 (2) Å	µ = 0.88 mm⁻¹
b = 8.9778 (10) Å	T = 173 K
c = 13.9263 (16) Å	0.40 × 0.14 × 0.14 mm
β = 127.051 (1)°

Data collection top

Bruker D8 diffractometer with a APEXII detector	2930 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2012)	2290 reflections with I > 2σ(I)
T_min = 0.606, T_max = 0.746	R_int = 0.018
3614 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.125	H-atom parameters constrained
S = 1.02	Δρ_max = 0.80 e Å⁻³
2930 reflections	Δρ_min = −0.47 e Å⁻³
150 parameters

Special details top

Experimental. Absorption correction: SADABS-2012/1 (Bruker,2012) was used for absorption correction. wR2(int) was 0.0566 before and 0.0407 after correction. The Ratio of minimum to maximum transmission is 0.8118. The λ/2 correction factor is 0.0015.

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.

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

	x	y	z	U_iso*/U_eq
H3	0.2131	−0.1861	0.3961	0.018*
H5	0.3214	0.0551	0.2858	0.021*
H6	0.1962	0.0922	0.1030	0.020*
H7	0.0799	−0.0063	0.0656	0.017*
H8a	0.3537	−0.1744	0.5242	0.018*
H8b	0.3996	−0.1315	0.4708	0.018*
H9a	0.3126	0.0166	0.5936	0.022*
H9b	0.2955	0.1475	0.5068	0.022*
H10a	0.3343	0.2306	0.6986	0.025*
H10b	0.3890	0.2984	0.6656	0.025*
H11a	0.4755	0.2883	0.9128	0.023*
H11b	0.5171	0.3117	0.8492	0.023*
H12a	0.3833	0.2132	0.4673	0.022*
H12b	0.4423	0.0940	0.4768	0.022*
C1	0.06017 (14)	−0.1928 (2)	0.19467 (19)	0.0158 (4)
C2	0.13474 (13)	−0.1115 (2)	0.22645 (18)	0.0134 (4)
C3	0.20986 (14)	−0.1300 (2)	0.33718 (19)	0.0148 (4)
C4	0.28076 (14)	−0.0671 (2)	0.36296 (18)	0.0139 (4)
C5	0.27494 (14)	0.0150 (3)	0.27221 (19)	0.0174 (5)
C6	0.19972 (15)	0.0363 (2)	0.16222 (19)	0.0171 (4)
C7	0.12995 (14)	−0.0239 (2)	0.13905 (19)	0.0143 (4)
C8	0.36136 (14)	−0.0955 (2)	0.48429 (19)	0.0153 (4)
C9	0.33771 (14)	0.0978 (3)	0.5810 (2)	0.0185 (5)
C10	0.37353 (14)	0.2069 (3)	0.6840 (2)	0.0205 (5)
C11	0.50015 (14)	0.2376 (2)	0.8806 (2)	0.0194 (5)
C12	0.42768 (14)	0.1462 (2)	0.52219 (19)	0.0184 (5)
N1	0.39880 (11)	0.03569 (18)	0.56797 (16)	0.0130 (4)
O1	0.07535 (10)	−0.31870 (17)	0.24829 (14)	0.0177 (3)
O2	−0.00750 (10)	−0.1403 (2)	0.11880 (15)	0.0266 (4)
O3	0.44337 (10)	0.13620 (18)	0.78732 (13)	0.0184 (3)
Co1	0.0000	−0.45483 (4)	0.2500	0.01262 (13)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0172 (12)	0.0174 (10)	0.0141 (9)	−0.0039 (8)	0.0102 (9)	−0.0025 (8)
C2	0.0121 (11)	0.0108 (9)	0.0152 (9)	−0.0006 (7)	0.0070 (8)	−0.0018 (7)
C3	0.0175 (11)	0.0117 (9)	0.0141 (9)	0.0000 (8)	0.0090 (9)	0.0014 (7)
C4	0.0128 (11)	0.0142 (10)	0.0121 (9)	0.0002 (7)	0.0062 (8)	−0.0003 (7)
C5	0.0153 (12)	0.0193 (11)	0.0161 (10)	−0.0031 (8)	0.0086 (9)	−0.0003 (8)
C6	0.0205 (12)	0.0151 (10)	0.0148 (9)	−0.0033 (8)	0.0103 (9)	0.0013 (8)
C7	0.0138 (11)	0.0138 (10)	0.0120 (9)	0.0012 (8)	0.0060 (8)	0.0005 (7)
C8	0.0132 (11)	0.0135 (9)	0.0154 (9)	0.0002 (8)	0.0066 (9)	−0.0007 (7)
C9	0.0120 (11)	0.0204 (11)	0.0165 (10)	0.0034 (8)	0.0052 (9)	0.0006 (8)
C10	0.0167 (12)	0.0202 (11)	0.0181 (10)	0.0061 (9)	0.0071 (9)	0.0003 (8)
C11	0.0162 (12)	0.0169 (11)	0.0178 (10)	0.0027 (8)	0.0064 (9)	−0.0049 (8)
C12	0.0178 (12)	0.0175 (10)	0.0153 (9)	−0.0032 (8)	0.0075 (9)	0.0035 (8)
N1	0.0104 (9)	0.0122 (8)	0.0139 (8)	−0.0011 (6)	0.0059 (7)	−0.0004 (6)
O1	0.0156 (8)	0.0148 (7)	0.0219 (8)	0.0001 (6)	0.0110 (7)	0.0024 (6)
O2	0.0132 (9)	0.0302 (10)	0.0244 (8)	−0.0007 (7)	0.0049 (7)	0.0103 (7)
O3	0.0140 (8)	0.0165 (7)	0.0152 (7)	0.0027 (6)	0.0037 (6)	−0.0016 (6)
Co1	0.0105 (2)	0.0114 (2)	0.0141 (2)	0.000	0.00639 (17)	0.000

Geometric parameters (Å, º) top

C1—C2	1.508 (3)	C11—H11b	0.9700
C2—C3	1.388 (3)	C11—C12ⁱ	1.515 (3)
C2—C7	1.402 (3)	C12—H12a	0.9700
C3—H3	0.9300	C12—H12b	0.9700
C4—C3	1.398 (3)	C12—C11ⁱ	1.515 (3)
C4—C8	1.516 (3)	N1—C8	1.502 (3)
C5—H5	0.9300	N1—C9	1.486 (3)
C5—C4	1.404 (3)	N1—C12	1.484 (3)
C6—H6	0.9300	N1—Co1ⁱⁱ	2.2212 (17)
C6—C5	1.388 (3)	O1—C1	1.285 (3)
C7—H7	0.9300	O2—C1	1.229 (3)
C7—C6	1.381 (3)	O3—C10	1.432 (3)
C8—H8a	0.9700	O3—C11	1.433 (3)
C8—H8b	0.9700	O3—Co1ⁱⁱ	2.2400 (16)
C9—H9a	0.9700	Co1—N1ⁱⁱⁱ	2.2213 (17)
C9—H9b	0.9700	Co1—N1ⁱⁱ	2.2213 (17)
C9—C10	1.511 (3)	Co1—O1	1.9886 (16)
C10—H10a	0.9700	Co1—O1^iv	1.9886 (16)
C10—H10b	0.9700	Co1—O3ⁱⁱⁱ	2.2399 (16)
C11—H11a	0.9700	Co1—O3ⁱⁱ	2.2399 (16)

O1—C1—C2	114.0 (2)	O3—C10—C9	106.67 (18)
O2—C1—C2	119.75 (19)	H11a—C11—H11b	108.6
O2—C1—O1	126.2 (2)	C12ⁱ—C11—H11a	110.3
C3—C2—C1	121.76 (19)	C12ⁱ—C11—H11b	110.3
C3—C2—C7	118.7 (2)	O3—C11—H11a	110.3
C7—C2—C1	119.40 (19)	O3—C11—H11b	110.3
C2—C3—H3	118.9	O3—C11—C12ⁱ	107.00 (17)
C2—C3—C4	122.10 (19)	H12a—C12—H12b	107.6
C4—C3—H3	118.9	C11ⁱ—C12—H12a	108.7
C3—C4—C5	118.2 (2)	C11ⁱ—C12—H12b	108.7
C3—C4—C8	119.56 (19)	N1—C12—H12a	108.7
C5—C4—C8	122.2 (2)	N1—C12—H12b	108.7
C4—C5—H5	120.1	N1—C12—C11ⁱ	114.25 (17)
C6—C5—H5	120.1	C8—N1—Co1ⁱⁱ	108.63 (12)
C6—C5—C4	119.9 (2)	C9—N1—C8	108.17 (17)
C5—C6—H6	119.4	C9—N1—Co1ⁱⁱ	105.43 (12)
C7—C6—H6	119.4	C12—N1—C8	110.02 (17)
C7—C6—C5	121.2 (2)	C12—N1—C9	113.03 (17)
C2—C7—H7	120.1	C12—N1—Co1ⁱⁱ	111.36 (13)
C6—C7—H7	120.1	C1—O1—Co1	128.97 (15)
C6—C7—C2	119.9 (2)	C10—O3—C11	114.03 (17)
H8a—C8—H8b	107.4	C10—O3—Co1ⁱⁱ	116.01 (13)
C4—C8—H8a	108.3	C11—O3—Co1ⁱⁱ	114.60 (13)
C4—C8—H8b	108.3	N1ⁱⁱⁱ—Co1—N1ⁱⁱ	141.85 (9)
N1—C8—H8a	108.3	N1ⁱⁱⁱ—Co1—O3ⁱⁱⁱ	76.37 (6)
N1—C8—H8b	108.3	N1ⁱⁱ—Co1—O3ⁱⁱⁱ	76.14 (6)
N1—C8—C4	116.03 (17)	N1ⁱⁱ—Co1—O3ⁱⁱ	76.37 (6)
H9a—C9—H9b	107.8	N1ⁱⁱⁱ—Co1—O3ⁱⁱ	76.14 (6)
C10—C9—H9a	108.9	O1—Co1—N1ⁱⁱ	90.61 (7)
C10—C9—H9b	108.9	O1^iv—Co1—N1ⁱⁱ	113.02 (7)
N1—C9—H9a	108.9	O1^iv—Co1—N1ⁱⁱⁱ	90.61 (7)
N1—C9—H9b	108.9	O1—Co1—N1ⁱⁱⁱ	113.02 (7)
N1—C9—C10	113.18 (19)	O1^iv—Co1—O1	104.15 (9)
H10b—C10—H10a	108.6	O1—Co1—O3ⁱⁱ	85.61 (6)
C9—C10—H10a	110.4	O1^iv—Co1—O3ⁱⁱⁱ	85.61 (6)
C9—C10—H10b	110.4	O1—Co1—O3ⁱⁱⁱ	165.96 (6)
O3—C10—H10a	110.4	O1^iv—Co1—O3ⁱⁱ	165.96 (6)
O3—C10—H10b	110.4	O3ⁱⁱⁱ—Co1—O3ⁱⁱ	86.74 (9)

C1—C2—C3—C4	173.4 (2)	C10—O3—C11—C12ⁱ	−175.92 (19)
C1—C2—C7—C6	−172.2 (2)	C11—O3—C10—C9	159.56 (19)
C2—C7—C6—C5	−1.7 (3)	C12—N1—C8—C4	−70.1 (2)
C3—C2—C7—C6	2.9 (3)	C12—N1—C9—C10	−71.2 (2)
C3—C4—C8—N1	−110.1 (2)	N1—C9—C10—O3	−49.7 (3)
C5—C4—C3—C2	−1.1 (3)	O1—C1—C2—C3	−28.4 (3)
C5—C4—C8—N1	73.0 (3)	O1—C1—C2—C7	146.5 (2)
C6—C5—C4—C3	2.4 (3)	O2—C1—C2—C3	155.1 (2)
C6—C5—C4—C8	179.3 (2)	O2—C1—C2—C7	−30.0 (3)
C7—C2—C3—C4	−1.5 (3)	Co1ⁱⁱ—N1—C8—C4	167.72 (15)
C7—C6—C5—C4	−1.0 (3)	Co1ⁱⁱ—N1—C9—C10	50.7 (2)
C8—C4—C3—C2	−178.10 (19)	Co1ⁱⁱ—N1—C12—C11ⁱ	−30.1 (2)
C8—N1—C9—C10	166.73 (18)	Co1—O1—C1—C2	172.68 (13)
C8—N1—C12—C11ⁱ	−150.6 (2)	Co1—O1—C1—O2	−11.1 (3)
C9—N1—C8—C4	53.8 (2)	Co1ⁱⁱ—O3—C10—C9	23.1 (2)
C9—N1—C12—C11ⁱ	88.3 (2)	Co1ⁱⁱ—O3—C11—C12ⁱ	−38.8 (2)

Symmetry codes: (i) −x+1, y, −z+3/2; (ii) −x+1/2, −y−1/2, −z+1; (iii) x−1/2, −y−1/2, z−1/2; (iv) −x, y, −z+1/2.

Experimental details

Crystal data
Chemical formula	[Co(C₂₄H₂₈N₂O₆)]
M_r	499.41
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	173
a, b, c (Å)	20.626 (2), 8.9778 (10), 13.9263 (16)
β (°)	127.051 (1)
V (Å³)	2058.2 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.88
Crystal size (mm)	0.40 × 0.14 × 0.14

Data collection
Diffractometer	Bruker D8 diffractometer with a APEXII detector
Absorption correction	Multi-scan (SADABS; Bruker, 2012)
T_min, T_max	0.606, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	3614, 2930, 2290
R_int	0.018
(sin θ/λ)_max (Å⁻¹)	0.729

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.125, 1.02
No. of reflections	2930
No. of parameters	150
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.80, −0.47

Computer programs: APEX2 (Bruker, 2011), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009).

Acknowledgements

Financial support of NSF/CREST/ CFNM (award No. HRD-1137751) is acknowledged.

References

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