Crystal structure of 4-(di­methyl­amino)­pyridinium cis-di­aqua­bis­(oxalato-κ²O,O′)ferrate(III) hemihydrate

In the title compound, the Fe^III atom is bonded to four O atoms from two chelating oxalate dianions and two O atoms from two cis aqua ligands. It has a slightly distorted octa­hedral coordination geometry. In the crystal, N—H...O and O—H...O hydrogen bonds play an important role in the structural self-assembly.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.042
• wR factor = 0.123
• Data-to-parameter ratio = 20.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT905_ALERT_3_C Negative K value in the Analysis of Variance ...     -1.953 Report
PLAT975_ALERT_2_C Check Calcd Residual Density  0.47A From     O3W       0.63 eA-3

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          8 Note
PLAT007_ALERT_5_G Number of Unrefined Donor-H Atoms ..............          1 Report
PLAT083_ALERT_2_G SHELXL Second Parameter in WGHT Unusually Large.       5.05 Why ?
PLAT172_ALERT_4_G The CIF-Embedded .res File Contains DFIX Records          5 Report
PLAT173_ALERT_4_G The CIF-Embedded .res File Contains DANG Records          3 Report
PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels ..........          4 Note
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............          8 Note
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Th(Min) ...          3 Report
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600         17 Note

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   9 ALERT level G = General information/check it is not something unexpected

   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
   3 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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Computing details

Data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009), publCIF (Westrip, 2010) and PLATON (Spek, 2009).

4-(Dimethylamino)pyridinium cis-diaquabis(oxalato-κ²O,O')ferrate(III) hemihydrate

Crystal data

(C7H11N2)[Fe(C2O4)2(H2O)2]·0.5H2O	F(000) = 1648
Mr = 800.22	Dx = 1.665 Mg m^−3
Monoclinic, I2/a	Mo Kα radiation, λ = 0.71073 Å
a = 14.7960 (7) Å	Cell parameters from 9923 reflections
b = 10.4422 (4) Å	θ = 2.2–27.3°
c = 21.7751 (10) Å	µ = 1.00 mm^−1
β = 108.352 (3)°	T = 296 K
V = 3193.2 (2) Å^3	Irregular, yellow
Z = 4	0.26 × 0.22 × 0.13 mm

Data collection

Bruker APEXII CCD diffractometer	3435 reflections with I > 2σ(I)
Radiation source: sealed X-ray tube	Rint = 0.044
φ and ω scans	θmax = 30.6°, θmin = 2.8°
Absorption correction: multi-scan (SADABS2014; Bruker, 2014)	h = −21→21
Tmin = 0.679, Tmax = 0.746	k = −14→14
48070 measured reflections	l = −31→31
4880 independent reflections

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)] = 0.042	Hydrogen site location: mixed
wR(F^2) = 0.123	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0528P)^2 + 5.0524P] where P = (Fo^2 + 2Fc^2)/3
4880 reflections	(Δ/σ)max = 0.001
239 parameters	Δρmax = 0.85 e Å^−3
8 restraints	Δρmin = −0.58 e Å^−3

Special details

Experimental. Absorption correction: SADABS-2014/3 (Bruker, 2014) was used for absorption correction. wR2(int) was 0.0678 before and 0.0491 after correction. The Ratio of minimum to maximum transmission is 0.9094. The λ/2 correction factor is 0.00150.

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 (Ų)

	x	y	z	Uiso*/Ueq
Fe1	0.33846 (2)	0.99760 (3)	0.33390 (2)	0.02994 (10)
O1	0.27198 (13)	0.84143 (16)	0.15711 (7)	0.0393 (4)
O1W	0.31148 (18)	1.14895 (18)	0.38270 (9)	0.0511 (5)
H1WA	0.287 (3)	1.216 (2)	0.3669 (16)	0.077*
H1WB	0.321 (3)	1.132 (4)	0.4186 (10)	0.077*
O2	0.23808 (16)	1.10293 (17)	0.14845 (8)	0.0524 (5)
O2W	0.21255 (12)	0.91604 (16)	0.33264 (9)	0.0381 (4)
H2WA	0.187 (2)	0.941 (3)	0.3590 (13)	0.057*
H2WB	0.223 (2)	0.8379 (17)	0.3394 (15)	0.057*
O3	0.33473 (12)	0.86776 (14)	0.26407 (7)	0.0343 (3)
O4	0.29136 (13)	1.10922 (15)	0.25610 (7)	0.0389 (4)
O5	0.39926 (12)	0.89364 (16)	0.41206 (8)	0.0398 (4)
O6	0.47565 (13)	1.04452 (18)	0.34780 (8)	0.0408 (4)
O7	0.53967 (14)	0.85689 (19)	0.48747 (9)	0.0504 (5)
O8	0.62163 (14)	1.0053 (2)	0.41370 (12)	0.0625 (6)
C1	0.29387 (15)	0.9073 (2)	0.20675 (10)	0.0293 (4)
C2	0.27184 (17)	1.0531 (2)	0.20161 (10)	0.0338 (5)
C3	0.49036 (17)	0.9055 (2)	0.43727 (11)	0.0335 (5)
C4	0.53485 (18)	0.9927 (2)	0.39683 (12)	0.0377 (5)
N1	0.34280 (18)	0.5649 (3)	0.47049 (11)	0.0564 (6)
H1	0.3107	0.5735	0.4302	0.068*
N2	0.49507 (17)	0.5221 (2)	0.66339 (10)	0.0442 (5)
C5	0.44607 (18)	0.5376 (2)	0.60033 (11)	0.0371 (5)
C6	0.4118 (3)	0.4314 (3)	0.55903 (14)	0.0609 (9)
H6	0.4241	0.3488	0.5756	0.073*
C7	0.3617 (3)	0.4484 (4)	0.49606 (15)	0.0683 (10)
H7	0.3400	0.3771	0.4700	0.082*
C8	0.3735 (2)	0.6686 (3)	0.50711 (14)	0.0518 (7)
H8	0.3599	0.7493	0.4885	0.062*
C9	0.42434 (19)	0.6587 (3)	0.57107 (13)	0.0438 (6)
H9	0.4448	0.7324	0.5955	0.053*
C10	0.5313 (2)	0.6307 (3)	0.70562 (14)	0.0521 (7)
H10A	0.5788	0.6742	0.6919	0.078*
H10B	0.5591	0.6011	0.7493	0.078*
H10C	0.4801	0.6885	0.7036	0.078*
C11	0.5175 (3)	0.3955 (3)	0.69141 (16)	0.0704 (10)
H11A	0.4600	0.3467	0.6833	0.106*
H11B	0.5480	0.4030	0.7372	0.106*
H11C	0.5596	0.3530	0.6723	0.106*
O3W	0.2500	0.1564 (4)	0.5000	0.117 (2)
H3W	0.302 (3)	0.115 (5)	0.512 (3)	0.176*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Fe1	0.03909 (18)	0.02585 (16)	0.02228 (15)	−0.00039 (12)	0.00595 (11)	−0.00107 (11)
O1	0.0583 (11)	0.0306 (8)	0.0283 (8)	−0.0001 (7)	0.0126 (7)	−0.0071 (6)
O1W	0.0945 (16)	0.0285 (9)	0.0335 (9)	0.0046 (9)	0.0247 (10)	−0.0040 (7)
O2	0.0879 (15)	0.0359 (9)	0.0250 (8)	0.0134 (9)	0.0059 (9)	0.0014 (7)
O2W	0.0401 (9)	0.0323 (8)	0.0426 (9)	0.0015 (7)	0.0141 (7)	−0.0069 (7)
O3	0.0490 (10)	0.0253 (7)	0.0270 (7)	0.0055 (6)	0.0099 (7)	−0.0007 (6)
O4	0.0615 (11)	0.0244 (8)	0.0252 (7)	0.0070 (7)	0.0058 (7)	−0.0026 (6)
O5	0.0411 (9)	0.0398 (9)	0.0349 (8)	−0.0073 (7)	0.0070 (7)	0.0109 (7)
O6	0.0430 (9)	0.0422 (9)	0.0349 (9)	−0.0037 (7)	0.0089 (7)	0.0125 (7)
O7	0.0505 (11)	0.0505 (11)	0.0431 (10)	0.0023 (8)	0.0047 (8)	0.0186 (8)
O8	0.0355 (10)	0.0863 (17)	0.0660 (14)	0.0012 (10)	0.0163 (9)	0.0341 (12)
C1	0.0349 (11)	0.0266 (10)	0.0281 (10)	0.0003 (8)	0.0121 (8)	−0.0021 (8)
C2	0.0442 (12)	0.0283 (10)	0.0273 (10)	0.0042 (9)	0.0088 (9)	−0.0016 (8)
C3	0.0412 (12)	0.0280 (10)	0.0308 (10)	0.0008 (9)	0.0106 (9)	0.0051 (8)
C4	0.0377 (12)	0.0379 (12)	0.0390 (12)	0.0001 (9)	0.0140 (10)	0.0058 (10)
N1	0.0565 (14)	0.0824 (19)	0.0260 (10)	0.0018 (13)	0.0071 (10)	0.0052 (11)
N2	0.0548 (13)	0.0377 (11)	0.0308 (10)	0.0045 (9)	−0.0001 (9)	−0.0004 (8)
C5	0.0457 (13)	0.0341 (11)	0.0293 (11)	0.0038 (10)	0.0086 (9)	−0.0016 (9)
C6	0.090 (2)	0.0377 (15)	0.0408 (14)	0.0106 (14)	0.0006 (14)	−0.0075 (12)
C7	0.088 (3)	0.063 (2)	0.0414 (16)	0.0035 (18)	0.0019 (15)	−0.0201 (15)
C8	0.0521 (16)	0.0561 (17)	0.0468 (15)	−0.0012 (13)	0.0152 (12)	0.0233 (13)
C9	0.0515 (15)	0.0350 (13)	0.0418 (13)	−0.0050 (10)	0.0101 (11)	0.0070 (10)
C10	0.0519 (16)	0.0573 (17)	0.0395 (13)	−0.0063 (13)	0.0032 (11)	−0.0116 (12)
C11	0.087 (2)	0.0517 (18)	0.0514 (17)	0.0136 (17)	−0.0089 (16)	0.0126 (14)
O3W	0.076 (3)	0.057 (2)	0.154 (4)	0.000	−0.056 (3)	0.000

Geometric parameters (Å, º)

Fe1—O1W	2.0133 (18)	N1—C7	1.330 (5)
Fe1—O2W	2.0407 (18)	N1—C8	1.337 (4)
Fe1—O3	2.0250 (15)	N2—C5	1.345 (3)
Fe1—O4	1.9927 (16)	N2—C10	1.452 (3)
Fe1—O5	1.9799 (16)	N2—C11	1.450 (4)
Fe1—O6	2.0163 (18)	C5—C6	1.417 (4)
O1—C1	1.235 (3)	C5—C9	1.407 (3)
O1W—H1WA	0.809 (17)	C6—H6	0.9300
O1W—H1WB	0.771 (17)	C6—C7	1.349 (4)
O2—C2	1.223 (3)	C7—H7	0.9300
O2W—H2WA	0.824 (17)	C8—H8	0.9300
O2W—H2WB	0.834 (17)	C8—C9	1.363 (4)
O3—C1	1.272 (3)	C9—H9	0.9300
O4—C2	1.272 (3)	C10—H10A	0.9600
O5—C3	1.291 (3)	C10—H10B	0.9600
O6—C4	1.269 (3)	C10—H10C	0.9600
O7—C3	1.218 (3)	C11—H11A	0.9600
O8—C4	1.226 (3)	C11—H11B	0.9600
C1—C2	1.554 (3)	C11—H11C	0.9600
C3—C4	1.550 (3)	O3W—H3W	0.842 (19)
N1—H1	0.8600
O1W—Fe1—O2W	90.16 (8)	O8—C4—O6	125.9 (2)
O1W—Fe1—O3	163.51 (8)	O8—C4—C3	119.0 (2)
O1W—Fe1—O6	95.03 (9)	C7—N1—H1	119.9
O3—Fe1—O2W	84.35 (7)	C7—N1—C8	120.2 (2)
O4—Fe1—O1W	85.14 (7)	C8—N1—H1	119.9
O4—Fe1—O2W	99.16 (8)	C5—N2—C10	121.7 (2)
O4—Fe1—O3	80.42 (6)	C5—N2—C11	121.2 (2)
O4—Fe1—O6	92.95 (7)	C11—N2—C10	117.1 (2)
O5—Fe1—O1W	95.09 (8)	N2—C5—C6	121.6 (2)
O5—Fe1—O2W	87.05 (7)	N2—C5—C9	122.9 (2)
O5—Fe1—O3	100.13 (7)	C9—C5—C6	115.5 (2)
O5—Fe1—O4	173.78 (7)	C5—C6—H6	119.5
O5—Fe1—O6	80.84 (7)	C7—C6—C5	121.0 (3)
O6—Fe1—O2W	167.19 (7)	C7—C6—H6	119.5
O6—Fe1—O3	93.64 (7)	N1—C7—C6	121.4 (3)
Fe1—O1W—H1WA	126 (3)	N1—C7—H7	119.3
Fe1—O1W—H1WB	110 (3)	C6—C7—H7	119.3
H1WA—O1W—H1WB	123 (3)	N1—C8—H8	119.2
Fe1—O2W—H2WA	118 (2)	N1—C8—C9	121.5 (3)
Fe1—O2W—H2WB	107 (2)	C9—C8—H8	119.2
H2WA—O2W—H2WB	107 (3)	C5—C9—H9	119.8
C1—O3—Fe1	114.30 (13)	C8—C9—C5	120.3 (3)
C2—O4—Fe1	116.08 (14)	C8—C9—H9	119.8
C3—O5—Fe1	116.33 (14)	N2—C10—H10A	109.5
C4—O6—Fe1	114.72 (15)	N2—C10—H10B	109.5
O1—C1—O3	126.2 (2)	N2—C10—H10C	109.5
O1—C1—C2	119.43 (19)	H10A—C10—H10B	109.5
O3—C1—C2	114.39 (17)	H10A—C10—H10C	109.5
O2—C2—O4	126.3 (2)	H10B—C10—H10C	109.5
O2—C2—C1	119.91 (19)	N2—C11—H11A	109.5
O4—C2—C1	113.77 (18)	N2—C11—H11B	109.5
O5—C3—C4	112.84 (19)	N2—C11—H11C	109.5
O7—C3—O5	126.3 (2)	H11A—C11—H11B	109.5
O7—C3—C4	120.9 (2)	H11A—C11—H11C	109.5
O6—C4—C3	115.1 (2)	H11B—C11—H11C	109.5
Fe1—O3—C1—O1	−170.06 (19)	O7—C3—C4—O6	−175.6 (2)
Fe1—O3—C1—C2	10.4 (2)	O7—C3—C4—O8	5.0 (4)
Fe1—O4—C2—O2	176.4 (2)	N1—C8—C9—C5	0.1 (4)
Fe1—O4—C2—C1	−3.0 (3)	N2—C5—C6—C7	179.1 (3)
Fe1—O5—C3—O7	174.7 (2)	N2—C5—C9—C8	−179.2 (3)
Fe1—O5—C3—C4	−4.7 (3)	C5—C6—C7—N1	0.1 (6)
Fe1—O6—C4—O8	178.3 (2)	C6—C5—C9—C8	0.0 (4)
Fe1—O6—C4—C3	−1.1 (3)	C7—N1—C8—C9	−0.2 (5)
O1—C1—C2—O2	−4.1 (4)	C8—N1—C7—C6	0.1 (5)
O1—C1—C2—O4	175.3 (2)	C9—C5—C6—C7	−0.2 (5)
O3—C1—C2—O2	175.4 (2)	C10—N2—C5—C6	179.2 (3)
O3—C1—C2—O4	−5.2 (3)	C10—N2—C5—C9	−1.6 (4)
O5—C3—C4—O6	3.8 (3)	C11—N2—C5—C6	1.9 (5)
O5—C3—C4—O8	−175.6 (2)	C11—N2—C5—C9	−178.8 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···O2^i	0.81 (2)	1.94 (2)	2.720 (3)	162 (4)
O1W—H1WB···O7^ii	0.77 (2)	2.40 (3)	2.988 (3)	134 (4)
O1W—H1WB···O3W^iii	0.77 (2)	2.34 (3)	2.9699 (19)	139 (4)
O2W—H2WA···O8^iv	0.82 (2)	1.84 (2)	2.664 (3)	176 (3)
O2W—H2WB···O1^v	0.83 (2)	1.88 (2)	2.702 (2)	171 (3)
N1—H1···O1^v	0.86	2.11	2.931 (3)	160
N1—H1···O2^v	0.86	2.46	3.043 (3)	125
O3W—H3W···O7^vi	0.84 (2)	2.36 (5)	3.040 (2)	138 (6)
O3W—H3W···O8^vi	0.84 (2)	2.09 (5)	2.782 (3)	140 (6)

Symmetry codes: (i) −x+1/2, −y+5/2, −z+1/2; (ii) −x+1, −y+2, −z+1; (iii) x, y+1, z; (iv) x−1/2, −y+2, z; (v) −x+1/2, −y+3/2, −z+1/2; (vi) −x+1, −y+1, −z+1.