catena-Poly[[aqua­(N,N-dimethyl­form­amide-κO)strontium(II)]-bis­[μ-2-(4-car­boxy­phen­oxy)propionato-κ³O,O′:O′]]

In the crystal structure of the polymeric title compound, [Sr(C₁₀H₉O₅)₂(C₃H₇NO)(H₂O)]_n, the Sr^II atom is O,O′-chelated by the carboxyl­ate end of two 2-(4-carboxy­phen­oxy)propionate monoanions, and is coordinated by a water mol­ecule and a dimethyl­formamide (DMF) mol­ecule. It also inter­acts with the carboxyl­ate O atom of two adjacent monoanions; these bonds give rise to a zigzag chain along the a axis. Meanwhile, the carboxyl –CO₂H end of the anion interacts with an acceptor site [O...O = 2.629 (4) Å]; this interaction and hydrogen bonding involving the water molecule [O...O = 3.191 (5) Å] give rise to a three-dimensional network. The eight coordinating O atoms comprise an irregular polyhedron around the metal atom. The Sr atom, the water O atom, and the N and O atoms of the DMF mol­ecule lie on a special position of site symmetry m; the DMF mol­ecule is disordered about the mirror plane.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.006 Å
• Disorder in main residue
• R factor = 0.059
• wR factor = 0.183
• Data-to-parameter ratio = 15.2

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.443     0.690
            Tmin(prime) and Tmax expected:      0.505     0.670
            RR(prime) =      0.852
            Please check that your absorption correction is appropriate.
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.83
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.97
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.08
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         O6
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Sr1
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N1
PLAT301_ALERT_3_C Main Residue  Disorder .........................       8.00 Perc.

Alert level G
PLAT793_ALERT_1_G Check the Absolute Configuration of C2     = ...          S

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 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

---

S1. Comment

This report continues previous studies on the transition metal derivatives of 2-[4-carboxyaltophenoxy]propionic acid (Deng et al., 2007a,b; Xiao et al., 2007). The studies are extended to the main-group metal derivatives. In the present strontium compound (Fig. 1), the metal shows irregular eight-coordination (Fig. 2).

Related literature

For transition metal derivatives of 2-[4-(carboxyphenoxy)propionic acid, see: Deng et al. (2007a,b); Xiao et al. (2007).

S2. Experimental

A solution of strontium carbonate (1 mmol) was added to a solution of 2-(4-carboxylatophenoxy)propionic acid (1 mmol) in DMF. The mixture was filtered and colourless were isolated after several days.

S3. Refinement

Carbon- and oxygen-bound H atoms were placed in calculated positions [C—H = 0.93–0.97 Å and U_iso(H) = 1.2–1.5U_eq(C); O–H = 0.82 Å and U_iso(H) = 1.5U_eq(O)], and were included in the refinement in the riding-model approximation. A rotating group model was used for the methyl and hydroxyl groups. The final difference Fourier map had large peaks/holes in the vicinity of the strontium atom.

Computing details

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC, 2002); 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. Part of the polymeric structure of the title compound, showing 50% probability displacement ellipsoids. H atoms are shown as small spheres of arbitrary radii. Symmetry codes: (i) x, 3/2 - y, z; (ii) 1/2 + x, 3/2 - y, 1/2 - z; (iii) 1/2 + x, y, 1/2 - z.
	Fig. 2. Irregular eight-coordinate geometry of Sr.

catena-Poly[[aqua(N,N-dimethylformamide-κO)strontium(II)]- bis[µ-2-(4-carboxyphenoxy)propionato-κ³O,O':O']]

Crystal data

[Sr(C10H9O5)2(C3H7NO)(H2O)]	F(000) = 1224
Mr = 597.08	Dx = 1.587 Mg m^−3
Orthorhombic, Pnma	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2n	Cell parameters from 21767 reflections
a = 7.8303 (3) Å	θ = 3.0–27.5°
b = 23.973 (1) Å	µ = 2.22 mm^−1
c = 13.3136 (5) Å	T = 295 K
V = 2499.17 (17) Å^3	Prism, colourless
Z = 4	0.30 × 0.24 × 0.18 mm

Data collection

Rigaku R-AXIS RAPID diffractometer	2917 independent reflections
Radiation source: fine-focus sealed tube	2218 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.087
Detector resolution: 10.000 pixels mm^-1	θmax = 27.5°, θmin = 3.0°
ω scans	h = −10→9
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −31→31
Tmin = 0.443, Tmax = 0.690	l = −17→17
36357 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.059	H-atom parameters constrained
wR(F^2) = 0.183	w = 1/[σ^2(Fo^2) + (0.1071P)^2 + 0.6055P] where P = (Fo^2 + 2Fc^2)/3
S = 1.17	(Δ/σ)max = 0.001
2917 reflections	Δρmax = 2.43 e Å^−3
192 parameters	Δρmin = −1.17 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.009 (2)

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
Sr1	0.29520 (6)	0.7500	0.32490 (4)	0.0362 (3)
O1	0.1965 (3)	0.64729 (13)	0.3671 (3)	0.0451 (7)
O2	0.0140 (4)	0.69144 (12)	0.2698 (2)	0.0495 (8)
O3	−0.0257 (4)	0.55897 (11)	0.3874 (2)	0.0433 (7)
O4	0.2868 (5)	0.36228 (16)	0.1218 (3)	0.0652 (10)
O5	0.1929 (4)	0.42171 (16)	0.0062 (3)	0.0608 (10)
H5o	0.2231	0.4013	−0.0400	0.091*
O6	0.5137 (6)	0.7500	0.4629 (4)	0.0636 (13)
O1W	0.1315 (8)	0.7500	0.5024 (4)	0.0707 (14)
H1W	0.1512	0.7793	0.5320	0.106*
N1	0.5613 (8)	0.7500	0.6316 (4)	0.0585 (15)
C1	0.0504 (5)	0.65244 (17)	0.3291 (3)	0.0371 (9)
C2	−0.0920 (5)	0.61218 (17)	0.3582 (3)	0.0425 (9)
H2	−0.1719	0.6077	0.3021	0.051*
C3	−0.1852 (6)	0.6352 (2)	0.4494 (4)	0.0587 (13)
H3A	−0.2794	0.6113	0.4658	0.088*
H3B	−0.2270	0.6720	0.4346	0.088*
H3C	−0.1080	0.6370	0.5053	0.088*
C4	0.0337 (5)	0.52473 (17)	0.3125 (3)	0.0402 (9)
C5	0.1010 (6)	0.47397 (18)	0.3454 (3)	0.0492 (10)
H5	0.1054	0.4658	0.4136	0.059*
C6	0.1603 (6)	0.43628 (18)	0.2766 (4)	0.0501 (11)
H6	0.2052	0.4025	0.2988	0.060*
C7	0.1548 (6)	0.44757 (19)	0.1737 (3)	0.0449 (10)
C8	0.0878 (6)	0.49822 (18)	0.1425 (4)	0.0456 (9)
H8	0.0829	0.5063	0.0742	0.055*
C9	0.0280 (6)	0.53707 (18)	0.2114 (4)	0.0448 (10)
H9	−0.0155	0.5711	0.1896	0.054*
C10	0.2186 (5)	0.4064 (2)	0.1001 (4)	0.0479 (10)
C11	0.5191 (12)	0.7256 (4)	0.5421 (8)	0.059 (2)	0.50
H11	0.4927	0.6878	0.5423	0.071*	0.50
C12	0.604 (2)	0.8030 (6)	0.6455 (10)	0.083 (4)	0.50
H12A	0.5590	0.8252	0.5916	0.124*	0.50
H12B	0.7263	0.8063	0.6466	0.124*	0.50
H12C	0.5582	0.8159	0.7081	0.124*	0.50
C13	0.5730 (19)	0.7093 (6)	0.7196 (10)	0.087 (4)	0.50
H13A	0.4955	0.7207	0.7716	0.130*	0.50
H13B	0.6875	0.7091	0.7454	0.130*	0.50
H13C	0.5434	0.6725	0.6971	0.130*	0.50

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Sr1	0.0357 (3)	0.0334 (3)	0.0396 (4)	0.000	0.0025 (2)	0.000
O1	0.0406 (16)	0.0403 (16)	0.0543 (19)	−0.0014 (11)	−0.0037 (12)	0.0109 (15)
O2	0.0512 (16)	0.0366 (16)	0.0608 (19)	−0.0029 (13)	−0.0145 (15)	0.0115 (14)
O3	0.0521 (16)	0.0323 (14)	0.0454 (16)	0.0016 (12)	0.0046 (13)	0.0018 (12)
O4	0.084 (3)	0.048 (2)	0.064 (2)	0.0150 (17)	0.0024 (18)	−0.0038 (18)
O5	0.076 (2)	0.058 (2)	0.048 (2)	0.0189 (17)	0.0067 (16)	−0.0077 (16)
O6	0.057 (3)	0.086 (4)	0.047 (3)	0.000	−0.008 (2)	0.000
O1W	0.071 (3)	0.082 (4)	0.058 (3)	0.000	0.010 (3)	0.000
N1	0.057 (3)	0.071 (4)	0.048 (3)	0.000	−0.006 (3)	0.000
C1	0.040 (2)	0.0340 (19)	0.037 (2)	0.0033 (16)	0.0008 (16)	−0.0024 (15)
C2	0.043 (2)	0.0330 (19)	0.051 (2)	0.0018 (17)	0.0028 (19)	0.0018 (17)
C3	0.062 (3)	0.041 (2)	0.073 (3)	0.003 (2)	0.019 (2)	0.001 (2)
C4	0.041 (2)	0.032 (2)	0.047 (2)	−0.0040 (17)	0.0019 (17)	−0.0019 (16)
C5	0.060 (3)	0.041 (2)	0.047 (2)	0.003 (2)	0.003 (2)	0.0070 (19)
C6	0.057 (2)	0.036 (2)	0.057 (3)	0.005 (2)	0.000 (2)	0.0029 (19)
C7	0.043 (2)	0.040 (2)	0.052 (3)	−0.0024 (19)	0.0035 (18)	−0.0019 (18)
C8	0.050 (2)	0.042 (2)	0.045 (2)	−0.0001 (19)	0.0000 (19)	0.0004 (18)
C9	0.051 (2)	0.034 (2)	0.050 (2)	0.0007 (18)	−0.0030 (19)	0.0026 (19)
C10	0.049 (2)	0.042 (2)	0.052 (3)	−0.0007 (19)	0.0019 (19)	−0.002 (2)
C11	0.062 (5)	0.049 (5)	0.065 (6)	−0.003 (4)	−0.001 (5)	0.002 (5)
C12	0.112 (11)	0.068 (8)	0.069 (8)	−0.021 (7)	−0.009 (8)	−0.009 (7)
C13	0.103 (10)	0.094 (10)	0.063 (7)	−0.009 (8)	−0.005 (7)	0.033 (7)

Geometric parameters (Å, º)

Sr1—O1	2.641 (3)	C2—H2	0.98
Sr1—O1^i	2.641 (3)	C3—H3A	0.96
Sr1—O2	2.712 (3)	C3—H3B	0.96
Sr1—O2^ii	2.549 (3)	C3—H3C	0.96
Sr1—O2^iii	2.549 (3)	C4—C9	1.379 (6)
Sr1—O2^i	2.712 (3)	C4—C5	1.396 (6)
Sr1—O6	2.511 (5)	C5—C6	1.368 (6)
Sr1—O1W	2.688 (5)	C5—H5	0.93
O1—C1	1.257 (5)	C6—C7	1.397 (6)
O2—C1	1.257 (5)	C6—H6	0.93
O3—C4	1.373 (5)	C7—C8	1.387 (6)
O3—C2	1.431 (5)	C7—C10	1.478 (6)
O4—C10	1.218 (6)	C8—C9	1.389 (6)
O5—C10	1.319 (6)	C8—H8	0.93
O5—H5o	0.82	C9—H9	0.93
O6—C11	1.206 (11)	C11—H11	0.93
O1W—H1W	0.82	C12—H12A	0.96
N1—C12	1.327 (13)	C12—H12B	0.96
N1—C11	1.368 (11)	C12—H12C	0.96
N1—C13	1.527 (12)	C13—H13A	0.96
C1—C2	1.525 (6)	C13—H13B	0.96
C2—C3	1.521 (6)	C13—H13C	0.96
O6—Sr1—O2^ii	84.48 (12)	O3—C2—C3	106.3 (4)
O6—Sr1—O2^iii	84.48 (12)	O3—C2—C1	111.6 (3)
O2^ii—Sr1—O2^iii	66.84 (13)	C3—C2—C1	108.9 (3)
O6—Sr1—O1^i	92.50 (8)	O3—C2—H2	110.0
O2^ii—Sr1—O1^i	77.79 (10)	C3—C2—H2	110.0
O2^iii—Sr1—O1^i	144.64 (10)	C1—C2—H2	110.0
O6—Sr1—O1	92.50 (8)	C2—C3—H3A	109.5
O2^ii—Sr1—O1	144.64 (10)	C2—C3—H3B	109.5
O2^iii—Sr1—O1	77.79 (10)	H3A—C3—H3B	109.5
O1^i—Sr1—O1	137.57 (14)	C2—C3—H3C	109.5
O6—Sr1—O1W	71.44 (18)	H3A—C3—H3C	109.5
O2^ii—Sr1—O1W	139.05 (11)	H3B—C3—H3C	109.5
O2^iii—Sr1—O1W	139.05 (11)	O3—C4—C9	124.7 (4)
O1^i—Sr1—O1W	70.93 (8)	O3—C4—C5	114.9 (4)
O1—Sr1—O1W	70.93 (8)	C9—C4—C5	120.3 (4)
O6—Sr1—O2	138.70 (10)	C6—C5—C4	119.6 (4)
O2^ii—Sr1—O2	134.19 (4)	C6—C5—H5	120.2
O2^iii—Sr1—O2	97.29 (8)	C4—C5—H5	120.2
O1^i—Sr1—O2	107.61 (9)	C5—C6—C7	121.2 (4)
O1—Sr1—O2	48.52 (9)	C5—C6—H6	119.4
O1W—Sr1—O2	81.42 (14)	C7—C6—H6	119.4
O6—Sr1—O2^i	138.70 (10)	C8—C7—C6	118.4 (4)
O2^ii—Sr1—O2^i	97.29 (8)	C8—C7—C10	121.0 (4)
O2^iii—Sr1—O2^i	134.19 (4)	C6—C7—C10	120.7 (4)
O1^i—Sr1—O2^i	48.52 (9)	C7—C8—C9	121.1 (4)
O1—Sr1—O2^i	107.61 (9)	C7—C8—H8	119.4
O1W—Sr1—O2^i	81.42 (14)	C9—C8—H8	119.4
O2—Sr1—O2^i	62.34 (12)	C4—C9—C8	119.4 (4)
C1—O1—Sr1	95.1 (2)	C4—C9—H9	120.3
C1—O2—Sr1^iv	150.8 (3)	C8—C9—H9	120.3
C1—O2—Sr1	91.8 (2)	O4—C10—O5	122.3 (5)
Sr1^iv—O2—Sr1	113.24 (10)	O4—C10—C7	124.8 (5)
C4—O3—C2	117.3 (3)	O5—C10—C7	113.0 (4)
C10—O5—H5o	120.0	O6—C11—N1	124.3 (9)
C11—O6—Sr1	131.5 (5)	O6—C11—H11	117.9
Sr1—O1W—H1W	109.5	N1—C11—H11	117.9
C12—N1—C11	126.2 (9)	N1—C12—H12A	109.5
C12—N1—C13	119.4 (10)	N1—C12—H12B	109.5
C11—N1—C13	114.2 (8)	N1—C12—H12C	109.5
O2—C1—O1	122.2 (4)	N1—C13—H13A	109.5
O2—C1—C2	117.7 (4)	N1—C13—H13B	109.5
O1—C1—C2	120.1 (4)	N1—C13—H13C	109.5
O6—Sr1—O1—C1	156.3 (3)	Sr1—O1—C1—O2	16.4 (4)
O2^ii—Sr1—O1—C1	−119.7 (3)	Sr1—O1—C1—C2	−160.7 (3)
O2^iii—Sr1—O1—C1	−119.9 (3)	C4—O3—C2—C3	167.1 (4)
O1^i—Sr1—O1—C1	59.8 (4)	C4—O3—C2—C1	−74.3 (4)
O1W—Sr1—O1—C1	86.9 (3)	O2—C1—C2—O3	154.9 (4)
O2—Sr1—O1—C1	−8.5 (2)	O1—C1—C2—O3	−27.9 (5)
O2^i—Sr1—O1—C1	12.9 (3)	O2—C1—C2—C3	−88.1 (5)
O6—Sr1—O2—C1	−14.9 (3)	O1—C1—C2—C3	89.2 (5)
O2^ii—Sr1—O2—C1	139.7 (2)	C2—O3—C4—C9	−2.6 (6)
O2^iii—Sr1—O2—C1	75.1 (2)	C2—O3—C4—C5	178.4 (4)
O1^i—Sr1—O2—C1	−130.4 (2)	O3—C4—C5—C6	178.6 (4)
O1—Sr1—O2—C1	8.5 (2)	C9—C4—C5—C6	−0.4 (7)
O1W—Sr1—O2—C1	−63.6 (2)	C4—C5—C6—C7	−0.1 (7)
O2^i—Sr1—O2—C1	−148.4 (2)	C5—C6—C7—C8	0.2 (7)
O6—Sr1—O2—Sr1^iv	149.72 (15)	C5—C6—C7—C10	−179.7 (4)
O2^ii—Sr1—O2—Sr1^iv	−55.74 (17)	C6—C7—C8—C9	0.2 (7)
O2^iii—Sr1—O2—Sr1^iv	−120.36 (18)	C10—C7—C8—C9	−179.9 (4)
O1^i—Sr1—O2—Sr1^iv	34.21 (16)	O3—C4—C9—C8	−178.1 (4)
O1—Sr1—O2—Sr1^iv	173.1 (2)	C5—C4—C9—C8	0.8 (6)
O1W—Sr1—O2—Sr1^iv	100.98 (14)	C7—C8—C9—C4	−0.7 (7)
O2^i—Sr1—O2—Sr1^iv	16.22 (16)	C8—C7—C10—O4	176.2 (4)
O1—Sr1—O6—C11	−28.6 (7)	C6—C7—C10—O4	−3.9 (7)
O1W—Sr1—O6—C11	40.3 (7)	C8—C7—C10—O5	−4.5 (6)
O2—Sr1—O6—C11	−11.3 (8)	C6—C7—C10—O5	175.4 (4)
Sr1—O2—C1—O1	−15.9 (4)	Sr1—O6—C11—N1	−133.9 (7)
Sr1^iv—O2—C1—C2	11.3 (8)	C12—N1—C11—O6	−0.8 (16)
Sr1—O2—C1—C2	161.2 (3)	C13—N1—C11—O6	−175.2 (10)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5O···O1^v	0.82	1.81	2.629 (4)	174
O1W—H1W···O4^vi	0.82	2.37	3.191 (5)	178

Symmetry codes: (v) −x+1/2, −y+1, z−1/2; (vi) −x+1/2, y+1/2, z+1/2.