Bis(di-2-pyridylmethane­diol-κ²N,N′)palladium(II) bis­(perchlorate)

In the title compound, [Pd(C₁₁H₁₀N₂O₂)₂](ClO₄)₂, the Pd^II atom, which lies on an inversion centre, adopts square-planar coordination, binding to the two N atoms of each of the two di-2-pyridylmethane­diol ligands. In the crystal structure, mol­ecules are linked by a network of O—H...O hydrogen bonds involving the hydroxyl groups and the O atoms of the perchlorate anions to form columns down a.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.046
• wR factor = 0.107
• Data-to-parameter ratio = 15.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.92
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT244_ALERT_4_C Low   'Solvent' Ueq as Compared to Neighbors for        Cl1
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          2
              Cl O4

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.923
            Tmax scaled      0.923 Tmin scaled      0.792
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K
PLAT794_ALERT_5_G Check Predicted Bond Valency for Pd1         (2)       2.20

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

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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
   3 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The crystal structure of (I) consists of [Pd(C₁₁H₁₀N₂O₂)₂]²⁺ cations and ClO₄^- anions (Fig. 1). In the cation, the metal atom lies on an inversion centre and binds to two N,N'-chelated di-2-pyridylmethanediol ligands in a square planar geometry. The Pd—N bond lengths are 2.025 (3) and 2.031 (3) Å. The N1—Pd—N2 angles are 86.97 (12) and 93.03 (12). A similar Pd(II) complex has already been reported by Sommerer et al. (1997).

In the crystal structure, there is a complex hydrogen-bonding network among the hydroxyl groups and the O atoms of the perchlorate anions, (Table 1, Fig. 2).

Related literature

A similar Pd^II square-planar complex of di-2-pyridylmethanediol has been reported by Sommerer et al. (1997).

S2. Experimental

The title complex was synthesized by refluxing a mixture of Pd(OAc)₂ (0.449 g, 2 mmol) and di-2-pyridylketone (0.185 g, 1 mmol) in ethanol/water (20 ml; 3:1 v/v) for 1 h with stirring. After cooling, solid NaClO₄.H₂O (0.210 g, 1.5 mmol) was added and the solution filtered. Yellow crystals of (I) suitable for X-ray analysis were obtained as plates by slow evaporation of the filtrate over two weeks.

S3. Refinement

H atoms were positioned geometrically and treated as riding atoms, with C—H distances of 0.93 Å and O—H distances of 0.82 Å, with U_iso(H) = 1.2 U_eq(C) and U_iso(H) = 1.5 U_eq(O).

Computing details

Data collection: CrystalClear (Rigaku, 2000); cell refinement: CrystalClear (Rigaku, 2000); data reduction: CrystalClear (Rigaku, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 1997).

Figures

	Fig. 1. The molecular structure of (I), with atom labels and 30% probability displacement ellipsoids for non-H atoms. Atoms with the A suffix are generated by the symmetry code (-x, 1 - y, -z).
	Fig. 2. A view of the crystal packing along the a axis. Hydrogen bonds are shown as dashed lines.

Bis(di-2-pyridylmethanediol-κ²N,N')palladium(II) bis(perchlorate)

Crystal data

[Pd(C11H10N2O2)2](ClO4)2	F(000) = 712
Mr = 709.72	Dx = 1.833 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2779 reflections
a = 7.677 (3) Å	θ = 3.1–27.5°
b = 13.929 (5) Å	µ = 1.00 mm^−1
c = 12.173 (5) Å	T = 293 K
β = 99.008 (5)°	Plate, yellow
V = 1285.7 (8) Å^3	0.40 × 0.20 × 0.08 mm
Z = 2

Data collection

Rigaku Mercury CCD diffractometer	2925 independent reflections
Radiation source: fine-focus sealed tube	2518 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.027
ω scans	θmax = 27.5°, θmin = 3.1°
Absorption correction: multi-scan (CrystalClear; Rigaku, 2000)	h = −9→9
Tmin = 0.858, Tmax = 1.000	k = −16→17
9661 measured reflections	l = −12→15

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.107	H-atom parameters constrained
S = 1.12	w = 1/[σ^2(Fo^2) + (0.0431P)^2 + 1.6859P] where P = (Fo^2 + 2Fc^2)/3
2925 reflections	(Δ/σ)max < 0.001
187 parameters	Δρmax = 0.62 e Å^−3
0 restraints	Δρmin = −0.60 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
Pd1	0.0000	0.5000	0.0000	0.03376 (13)
Cl1	−0.15333 (17)	0.38024 (9)	−0.41355 (9)	0.0642 (3)
C1	0.3177 (5)	0.4007 (3)	−0.0473 (3)	0.0456 (9)
H1A	0.2952	0.3615	0.0107	0.055*
C2	0.4601 (5)	0.3814 (3)	−0.0988 (4)	0.0582 (11)
H2A	0.5330	0.3293	−0.0767	0.070*
C3	0.4931 (6)	0.4395 (4)	−0.1826 (4)	0.0671 (13)
H3A	0.5887	0.4270	−0.2189	0.081*
C4	0.3849 (6)	0.5173 (4)	−0.2141 (4)	0.0594 (12)
H4A	0.4081	0.5579	−0.2707	0.071*
C5	0.2432 (5)	0.5337 (3)	−0.1610 (3)	0.0433 (8)
C6	0.1147 (6)	0.6181 (3)	−0.1892 (3)	0.0490 (9)
C7	0.0762 (5)	0.6930 (3)	0.0970 (3)	0.0459 (9)
H7A	0.0411	0.6648	0.1592	0.055*
C8	0.1333 (6)	0.7865 (3)	0.1033 (4)	0.0560 (11)
H8A	0.1390	0.8210	0.1692	0.067*
C9	0.1817 (6)	0.8280 (3)	0.0109 (4)	0.0633 (12)
H9A	0.2187	0.8916	0.0132	0.076*
C10	0.1758 (6)	0.7757 (3)	−0.0853 (4)	0.0543 (10)
H10A	0.2097	0.8034	−0.1482	0.065*
C11	0.1187 (5)	0.6813 (3)	−0.0876 (3)	0.0410 (8)
N1	0.2095 (4)	0.4751 (2)	−0.0785 (2)	0.0378 (7)
N2	0.0696 (4)	0.6408 (2)	0.0028 (2)	0.0376 (6)
O1	−0.0599 (4)	0.5845 (2)	−0.2184 (2)	0.0600 (8)
H1B	−0.0597	0.5349	−0.2546	0.090*
O2	0.1675 (5)	0.6744 (2)	−0.2722 (3)	0.0781 (11)
H2B	0.1414	0.6475	−0.3325	0.117*
O3	−0.2926 (7)	0.4402 (4)	−0.4044 (7)	0.164 (3)
O4	−0.1980 (10)	0.2889 (3)	−0.3818 (5)	0.166 (3)
O5	−0.0060 (6)	0.4159 (3)	−0.3402 (3)	0.0981 (13)
O6	−0.1158 (11)	0.3796 (8)	−0.5176 (4)	0.236 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pd1	0.0400 (2)	0.0271 (2)	0.0341 (2)	0.00115 (15)	0.00552 (14)	−0.00030 (15)
Cl1	0.0799 (8)	0.0667 (7)	0.0469 (6)	−0.0032 (6)	0.0133 (5)	−0.0136 (5)
C1	0.045 (2)	0.036 (2)	0.054 (2)	0.0021 (16)	0.0036 (17)	−0.0038 (17)
C2	0.044 (2)	0.054 (3)	0.075 (3)	0.0073 (19)	0.005 (2)	−0.016 (2)
C3	0.051 (2)	0.082 (4)	0.073 (3)	0.002 (2)	0.022 (2)	−0.020 (3)
C4	0.061 (3)	0.072 (3)	0.049 (2)	−0.012 (2)	0.019 (2)	−0.003 (2)
C5	0.055 (2)	0.0387 (19)	0.0360 (18)	−0.0066 (17)	0.0056 (16)	−0.0055 (16)
C6	0.070 (3)	0.041 (2)	0.0345 (18)	−0.0004 (19)	0.0032 (17)	0.0061 (16)
C7	0.047 (2)	0.042 (2)	0.049 (2)	0.0009 (17)	0.0074 (17)	−0.0119 (17)
C8	0.055 (2)	0.045 (2)	0.068 (3)	−0.0016 (19)	0.006 (2)	−0.023 (2)
C9	0.069 (3)	0.031 (2)	0.089 (3)	−0.006 (2)	0.008 (3)	−0.010 (2)
C10	0.071 (3)	0.036 (2)	0.056 (2)	−0.0048 (19)	0.009 (2)	0.0049 (18)
C11	0.048 (2)	0.0318 (18)	0.0414 (19)	0.0000 (15)	0.0018 (16)	0.0016 (15)
N1	0.0423 (16)	0.0341 (15)	0.0372 (15)	0.0008 (12)	0.0069 (12)	−0.0038 (12)
N2	0.0438 (15)	0.0294 (15)	0.0388 (15)	−0.0012 (13)	0.0040 (12)	−0.0023 (12)
O1	0.071 (2)	0.0484 (16)	0.0521 (17)	0.0097 (14)	−0.0167 (14)	−0.0082 (13)
O2	0.135 (3)	0.0552 (19)	0.0451 (17)	−0.007 (2)	0.0183 (19)	0.0136 (15)
O3	0.109 (4)	0.096 (4)	0.297 (9)	0.020 (3)	0.066 (5)	0.006 (5)
O4	0.246 (7)	0.054 (3)	0.171 (5)	−0.029 (3)	−0.049 (5)	−0.009 (3)
O5	0.107 (3)	0.095 (3)	0.085 (3)	−0.013 (2)	−0.007 (2)	−0.034 (2)
O6	0.235 (8)	0.432 (13)	0.052 (3)	−0.126 (9)	0.055 (4)	−0.075 (5)

Geometric parameters (Å, º)

Pd1—N1	2.025 (3)	C5—N1	1.351 (5)
Pd1—N1^i	2.025 (3)	C5—C6	1.538 (6)
Pd1—N2^i	2.031 (3)	C6—O2	1.389 (5)
Pd1—N2	2.031 (3)	C6—O1	1.411 (5)
Cl1—O6	1.342 (5)	C6—C11	1.515 (5)
Cl1—O3	1.375 (5)	C7—N2	1.352 (4)
Cl1—O4	1.389 (5)	C7—C8	1.373 (6)
Cl1—O5	1.416 (4)	C7—H7A	0.9300
C1—N1	1.345 (5)	C8—C9	1.366 (7)
C1—C2	1.370 (6)	C8—H8A	0.9300
C1—H1A	0.9300	C9—C10	1.374 (6)
C2—C3	1.357 (7)	C9—H9A	0.9300
C2—H2A	0.9300	C10—C11	1.385 (5)
C3—C4	1.382 (7)	C10—H10A	0.9300
C3—H3A	0.9300	C11—N2	1.342 (5)
C4—C5	1.370 (6)	O1—H1B	0.8200
C4—H4A	0.9300	O2—H2B	0.8200
N1—Pd1—N1^i	180.0	O2—C6—C11	107.1 (3)
N1—Pd1—N2^i	93.03 (12)	O1—C6—C11	107.2 (3)
N1^i—Pd1—N2^i	86.97 (12)	O2—C6—C5	110.1 (4)
N1—Pd1—N2	86.97 (12)	O1—C6—C5	110.7 (3)
N1^i—Pd1—N2	93.03 (12)	C11—C6—C5	109.4 (3)
N2^i—Pd1—N2	180.0	N2—C7—C8	121.8 (4)
O6—Cl1—O3	111.4 (6)	N2—C7—H7A	119.1
O6—Cl1—O4	110.8 (5)	C8—C7—H7A	119.1
O3—Cl1—O4	107.8 (4)	C9—C8—C7	118.7 (4)
O6—Cl1—O5	109.2 (4)	C9—C8—H8A	120.6
O3—Cl1—O5	106.9 (4)	C7—C8—H8A	120.6
O4—Cl1—O5	110.7 (3)	C8—C9—C10	120.0 (4)
N1—C1—C2	121.6 (4)	C8—C9—H9A	120.0
N1—C1—H1A	119.2	C10—C9—H9A	120.0
C2—C1—H1A	119.2	C9—C10—C11	119.3 (4)
C3—C2—C1	118.9 (4)	C9—C10—H10A	120.4
C3—C2—H2A	120.6	C11—C10—H10A	120.4
C1—C2—H2A	120.6	N2—C11—C10	120.7 (4)
C2—C3—C4	120.1 (4)	N2—C11—C6	116.9 (3)
C2—C3—H3A	120.0	C10—C11—C6	122.3 (4)
C4—C3—H3A	120.0	C1—N1—C5	119.6 (3)
C5—C4—C3	119.2 (4)	C1—N1—Pd1	120.0 (3)
C5—C4—H4A	120.4	C5—N1—Pd1	120.4 (3)
C3—C4—H4A	120.4	C11—N2—C7	119.4 (3)
N1—C5—C4	120.6 (4)	C11—N2—Pd1	119.9 (2)
N1—C5—C6	115.9 (3)	C7—N2—Pd1	120.6 (3)
C4—C5—C6	123.5 (4)	C6—O1—H1B	109.5
O2—C6—O1	112.2 (3)	C6—O2—H2B	109.5

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1B···O5	0.82	2.03	2.842 (5)	169
O2—H2B···O6^ii	0.82	1.84	2.636 (6)	162

Symmetry code: (ii) −x, −y+1, −z−1.