Poly[di-μ₂-chlorido(μ₂-1,3-di-4-pyridylpropane-κ²N:N′)lead(II)]

The title Pb^II coordination polymer, [PbCl₂(C₁₃H₁₄N₂)], was prepared by the hydro­thermal reaction of PbCl₂ with 4,4,-trimethyl­enedipyridine in a 1:1 ratio. It exhibits a two-dimensional layered structural motif consisting of PbCl₂ chains and the flexible bridged 4,4′-trimethyl­enedipyridine ligand. The connections result in a cavity of about 4 × 15 Å.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.011 Å
• R factor = 0.033
• wR factor = 0.077
• Data-to-parameter ratio = 14.6

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.95
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Pb1    --  Cl1     ..      17.47 su
PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X)  Pb1    --  Cl2     ..      15.54 su

Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Pb1
PLAT342_ALERT_3_C Low Bond Precision on  C-C Bonds (x 1000) Ang ..         11

Alert level G
PLAT764_ALERT_4_G Overcomplete CIF Bond List Detected (Rep/Expd) .       1.21 Ratio

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

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

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S1. Comment

Crystal engineering based upon transition metal coordination polymers has made rapid progress (Abrahams et al., 1999). These metal organic frameworks attracted much attention in the field of host guest chemistry (Natarajan et al., 2009), which may find applications in catalysis, nonlinear optics, magnetism, molecular recognition and separation (Moulton et al., 2001). By comparison, the networks with main group metals as connected nodes have not been well documented (Shi et al., 2002). Recently, many lead halides based coordination polymers with nitrogen-containing ligand as bridge exhibit interesting physical properties and structural motifs (Nordell et al., 2004). Different linkers, such as 4,4,-bipy, pyrazine and bipyridyl-based butadiene are introduced to the construction of lead halide organic-inorganic hybrid compounds. Here we report the hydrothermal synthesis and structural characterization of a new coordination complex based on PbCl₂ inorganic unit and 4,4,-trimethylenedipyridine. Hydrothermal reaction of PbCl₂ and 4,4,-trimethylenedipyridine with equimolar amounts afford block-like crystals. They were characterized by single-crystal X-ray structural analysis. Details of crystallographic data for the title compounds 1 is listed in Table 1. The structure of PbCl2(4,4,-trimethylenedipyridine) framework is a two-dimensional-layered motif constructed by the [PbCl₂]_n chains and the flexible bridge 4,4,-trimethylenedipyridine ligand (Fig. 1). The crystal is monoclinic, space group P21/m, with the Pb, Cl1 and Cl2 atoms lying on a crystallographic mirror plane. Each lead metal center is six-coordinate geometry with four chloride ion on the square plane and two nitrogen donors at the axial direction. The bond distances of Pb—Cl range from 2.862 (6) Å to 2.982 (6) Å. And the bond distance of Pb—N is 2.667 (7) Å. These parameters are close to previous report (Nordell et al., 2004). The bond angles of Cl—Pb—Cl at the square plane vary from 81.15 (17) to 97.21 (17)°. And the trans N1—Pb1—N1 bond angle is 166.1 (3)°. These value indicate that the lead center is situated in a distorted octahedral environment and the lone pair in Pb(II) is stereochemically active. As showed in figure 2, The [PbCl₂]_n chains are linked into flat sheets by the 4,4,-trimethylenedipyridine bridges. The dimensions of the distorted square cavity are approximately 4*15 Å. The flexible of the spacers make the layer into an undulating structural motif. And the sheets stack along a axis at a distance of 4.69 Å.

Related literature

For crystal engineering based upon transition metal coordination polymers, see: Abrahams et al. (1999). For applications of these metal-organic frameworks, see: Moulton & Zaworotko (2001); Natarajan & Mahata (2009). For networks with main group metals as connected nodes, see: Shi et al. (2002). For the related structure, [PbCl₂(4,4'-bipy)] (bipy is bipyridine), see: Nordell et al. (2004).

S2. Experimental

An aqueous mixture (10 ml) containing 4,4,-trimethylenedipyridine (0.1 g, 0.5 mmol), PbCl₂ (0.139 g, 0.5 mmol) was placed in a Parr Teflonlined stainless steel vessel (25 ml), and the vessel was sealed and heated to 403.15 K for 24 h. 0.08 g block-like crystals were obtained.

S3. Refinement

H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93–0.97 Å and with U_iso(H) = 1.2 (1.5 for methyl groups) times U_eq(C). The non-hydrogen atoms were refined anisotropically. 41 low-theta reflections were omitted from the data set.

Computing details

Data collection: SMART (Bruker, 1996); cell refinement: SMART (Bruker, 1996) and SAINT (Bruker, 1996)'; data reduction: SHELXTL (Sheldrick, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

	Fig. 1. The molecular structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms.
	Fig. 2. The packing of (I), viewed down the c axis.

Poly[di-µ₂-chlorido(µ₂-1,3-di-4-pyridylpropane- κ²N:N')lead(II)]

Crystal data

[PbCl2(C13H14N2)]	F(000) = 444
Mr = 476.35	Dx = 2.155 Mg m^−3
Monoclinic, P21/m	Melting point: 533.15K K
Hall symbol: -P2yb	Mo Kα radiation, λ = 0.71073 Å
a = 4.385 (2) Å	Cell parameters from 1283 reflections
b = 15.455 (3) Å	θ = 2.6–25.0°
c = 10.935 (2) Å	µ = 11.84 mm^−1
β = 97.65 (2)°	T = 298 K
V = 734.5 (3) Å^3	Block, yellow
Z = 2	0.19 × 0.15 × 0.11 mm

Data collection

Bruker SMART CCD diffractometer	1283 independent reflections
Radiation source: fine-focus sealed tube	1109 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
ω scans	θmax = 25.0°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −5→5
Tmin = 0.139, Tmax = 0.277	k = −15→18
2401 measured reflections	l = −7→12

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.077	H-atom parameters constrained
S = 1.01	w = 1/[σ^2(Fo^2) + (0.0359P)^2] where P = (Fo^2 + 2Fc^2)/3
1283 reflections	(Δ/σ)max < 0.001
88 parameters	Δρmax = 0.88 e Å^−3
0 restraints	Δρmin = −1.16 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Pb1	0.32077 (9)	0.7500	0.28349 (4)	0.03780 (17)
Cl2	0.7798 (10)	0.7500	0.1052 (3)	0.0748 (10)
Cl1	−0.1094 (10)	0.7500	0.4619 (3)	0.0719 (10)
C5	0.6217 (18)	0.4150 (5)	0.2292 (8)	0.0431 (19)
N1	0.3822 (16)	0.5787 (4)	0.2702 (7)	0.0482 (17)
C2	0.412 (2)	0.4554 (5)	0.1409 (8)	0.049 (2)
H2A	0.3481	0.4278	0.0662	0.059*
C3	0.574 (2)	0.5401 (5)	0.3555 (8)	0.057 (2)
H3A	0.6288	0.5684	0.4303	0.068*
C1	0.297 (2)	0.5358 (5)	0.1631 (8)	0.049 (2)
H1A	0.1573	0.5616	0.1026	0.059*
C6	0.770 (2)	0.3312 (5)	0.2033 (9)	0.055 (2)
H6A	0.9711	0.3283	0.2527	0.066*
H6B	0.8024	0.3302	0.1171	0.066*
C31	0.698 (2)	0.4595 (5)	0.3397 (9)	0.055 (2)
H3B	0.8335	0.4349	0.4030	0.066*
C7	0.584 (2)	0.2500	0.2302 (11)	0.040 (3)
H7A	0.3863	0.2500	0.1783	0.048*
H7C	0.5474	0.2500	0.3159	0.048*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pb1	0.0342 (2)	0.0274 (2)	0.0527 (3)	0.000	0.00873 (17)	0.000
Cl2	0.095 (3)	0.082 (2)	0.047 (2)	0.000	0.0061 (17)	0.000
Cl1	0.102 (3)	0.065 (2)	0.048 (2)	0.000	0.0045 (18)	0.000
C5	0.043 (5)	0.026 (4)	0.066 (6)	−0.005 (3)	0.027 (4)	0.002 (4)
N1	0.057 (4)	0.027 (3)	0.062 (5)	0.006 (3)	0.016 (4)	0.006 (3)
C2	0.062 (5)	0.032 (4)	0.052 (5)	−0.003 (4)	0.008 (4)	−0.003 (4)
C3	0.081 (7)	0.032 (4)	0.056 (6)	0.002 (4)	0.003 (5)	−0.001 (4)
C1	0.053 (5)	0.032 (4)	0.059 (6)	−0.002 (4)	−0.002 (4)	0.009 (4)
C6	0.056 (5)	0.032 (4)	0.083 (7)	−0.002 (4)	0.029 (5)	0.004 (4)
C31	0.060 (6)	0.040 (4)	0.066 (6)	−0.007 (4)	0.005 (5)	0.006 (4)
C7	0.035 (6)	0.023 (5)	0.064 (7)	0.000	0.012 (5)	0.000

Geometric parameters (Å, º)

Pb1—N1^i	2.667 (7)	C2—C1	1.374 (10)
Pb1—N1	2.667 (7)	C2—H2A	0.9300
Pb1—Cl2^ii	2.862 (6)	C3—C31	1.379 (11)
Pb1—Cl1	2.887 (5)	C3—H3A	0.9300
Pb1—Cl1^iii	2.957 (6)	C1—H1A	0.9300
Pb1—Cl2	2.982 (6)	C6—C7	1.548 (10)
Cl2—Pb1^iii	2.862 (6)	C6—H6A	0.9700
Cl1—Pb1^ii	2.957 (6)	C6—H6B	0.9700
C5—C31	1.392 (12)	C31—H3B	0.9300
C5—C2	1.390 (12)	C7—C6^iv	1.548 (10)
C5—C6	1.494 (11)	C7—H7A	0.9700
N1—C3	1.313 (11)	C7—H7C	0.9700
N1—C1	1.354 (11)
N1^i—Pb1—N1	166.1 (3)	C1—C2—H2A	119.8
N1^i—Pb1—Cl2^ii	92.49 (16)	C5—C2—H2A	119.8
N1—Pb1—Cl2^ii	92.49 (16)	N1—C3—C31	123.2 (8)
N1^i—Pb1—Cl1	96.69 (14)	N1—C3—H3A	118.4
N1—Pb1—Cl1	96.69 (14)	C31—C3—H3A	118.4
Cl2^ii—Pb1—Cl1	84.43 (17)	N1—C1—C2	122.1 (7)
N1^i—Pb1—Cl1^iii	87.32 (16)	N1—C1—H1A	119.0
N1—Pb1—Cl1^iii	87.32 (16)	C2—C1—H1A	119.0
Cl2^ii—Pb1—Cl1^iii	178.36 (9)	C5—C6—C7	114.3 (7)
Cl1—Pb1—Cl1^iii	97.21 (17)	C5—C6—H6A	108.7
N1^i—Pb1—Cl2	83.26 (14)	C7—C6—H6A	108.7
N1—Pb1—Cl2	83.26 (14)	C5—C6—H6B	108.7
Cl2^ii—Pb1—Cl2	97.21 (17)	C7—C6—H6B	108.7
Cl1—Pb1—Cl2	178.36 (11)	H6A—C6—H6B	107.6
Cl1^iii—Pb1—Cl2	81.15 (17)	C3—C31—C5	120.1 (8)
Pb1^iii—Cl2—Pb1	97.21 (17)	C3—C31—H3B	120.0
Pb1—Cl1—Pb1^ii	97.21 (17)	C5—C31—H3B	120.0
C31—C5—C2	116.2 (7)	C6—C7—C6^iv	108.3 (9)
C31—C5—C6	122.2 (8)	C6—C7—H7A	110.0
C2—C5—C6	121.5 (8)	C6^iv—C7—H7A	110.0
C3—N1—C1	117.9 (7)	C6—C7—H7C	110.0
C3—N1—Pb1	118.2 (6)	C6^iv—C7—H7C	110.0
C1—N1—Pb1	121.0 (5)	H7A—C7—H7C	108.4
C1—C2—C5	120.5 (8)

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