Tetrakis(dimethyl sulfide)palladium(II) bis(tetrafluoroborate) and tetrakis(1,4-oxathiane-[kappa]S)palladium(II) bis(tetrafluoroborate)

Tetrakis(dimethyl sulfide)palladium(II) bis(tetrafluoroborate), [Pd(C₂H₆S)₄](BF₄)₂, (I), and tetrakis(1,4-oxa­thiane-[kappa]S)palladium(II) bis­(tetra­fluoro­borate), [Pd(C₄H₈OS)₄](BF₄)₂, (II), both crystallize as mononuclear square-planar complexes with tetra­fluoro­borate as the counter-ions. The Pd atom accepts four S-donor atoms and is positioned at an inversion centre in both compounds. The two unique S atoms in the di­methyl sulfide complex, (I), are disordered. The Pd-S distances are in the range 2.3338 (12)-2.3375 (12) Å in (I), and the corresponding distances in the thio­xane complex, (II), are 2.3293 (17) and 2.3406 (17) Å. The anions in both compounds interact weakly with the Pd atom.

S1. Comment

The 1,4-oxathiane (tx) ligand possesses two potential donor sites, i.e. the S and the O atoms. Pd^II and Pt^II are soft acceptors and sulfur bonding is predominant, but in the tetrakis(dimethyl sulfoxide) complexes of Pd^II and Pt^II, two S-bonded and two O-bonded ligands are observed in a cis-arrangement (Johnson et al., 1981; Elding & Oskarsson, 1987). A previously determined palladium(II) tetrakis(1,4-oxathiane) structure, [Pd(tx)₄](BF₄)₂·4CH₃NO₂ (Moullet et al., 1997), was found to contain four S-bonded tx ligands, and the same arrangement was found for the platinum compound [Pt(tx)₄](CF₃SO₃)₂·H₂O (Bugarcic et al., 1991). There seems to be no reported crystal structure for a Pd complex with four dimethyl sulfide ligands (dms), but for Pt^II, the crystal structure of [Pt(dms)₄](CF₃SO₃)₂ is known (Bugarcic et al., 1991).

The structures of the title compounds, (I) and (II), have been determined firstly in order to study possible differences in bonding to Pd^II between a small thioether ligand, dimethylsulfide (dms), and a larger ambidentate ligand, 1,4-oxathiane (tx), with certain steric demands imposed by the ring structure, and secondly, to make geometric comparisons with analogous Pt^II complexes. \sch

The structure of (I) is shown in Fig. 1 and selected geometric parameters are given in Table 1. The compound consists of a square-planar mononuclear cationic complex, [Pd(dms)₄]²⁺, with BF₄^- as counterions. The Pd atom is positioned at an inversion centre, giving a perfectly planar PdS₄ coordination with S—Pd—S angles of 89.60 (5) and 90.40 (5)°. The dms groups are disordered, as the S atom occupies two different positions, with occupancy factors refined to 0.875 (3) for S1 and S2, and 0.125 (3) for S1' and S2'. The same type of disorder was reported for [Pt(dms)₄](CF₃SO₃)₂ (Bugarcic et al., 1991). The C atoms have a paddle-wheel-like arrangement, i.e. they are staggered with respect to the coordination plane and all directed in the same way. One tetrafluoroborate anion is located on each side of the coordination plane, completing an approximate octahedral coordination of the Pd atom, with the shortest distance to Pd being 3.142 (1) Å for Pd—F2(x, y, z; -x, -y, -z) (Fig. 1).

The structure of (II) is shown in Fig. 2 and selected geometric parameters are given in Table 2. The compound consists of a square-planar mononuclear cationic complex, [Pd(tx)₄]²⁺, with S-bonded tx ligands and with BF₄^- as counterions. The Pd atom is positioned at an inversion centre, giving perfect planar coordination around the metal with S—Pd—S angles of 89.48 (6) and 90.52 (6)°. The tx ligands have a chair conformation. The two C atoms bonded to S in each of these ligands adopt the same paddle-wheel like conformation found in the dms complex. Three of the four F atoms in the tetrafluoroborate ions are disordered over two positions, with approximately 50% in each position, while one F position is fully occupied. The tetrafluoroborate ions are located on each side of the coordination plane, giving an approximately octahedral coordination of the Pd atom, with the closest interaction with Pd being 2.87 (8) Å for Pd—F2(1 + x, y, z; -1 - x, -y, -z) and 3.00 (6) Å for Pd—F3'(1 + x, y, z; -1 - x, -y, -z) (Fig. 2).

The arrangement of the thioether ligands around Pd in (I) is similar to the geometry found in [Pd(tx)₄](BF₄)₂·4CH₃NO₂ (Moullet et al., 1997) and in the analogous Pt compounds [Pt(dms)₄](CF₃SO₃)₂ and [Pt(tx)₄](CF₃SO₃)₂·H₂O (Bugarcic et al., 1991). The dms ligands are found to be disordered in a similar fashion in the Pt-dms complex. The geometry of the tx ligands in (II) is also similar to that found for [Pd(tx)₄](BF₄)₂·4CH₃NO₂, but with slightly shorter S—C distances, in the range 1.782 (8)–1.809 (7) Å, compared with 1.806 (4)–1.827 (4) Å.

In the earlier reported tetrakis(thioxane) Pd complex (Moullet et al., 1997), the CH₃NO₂ solvent molecules occupy the octahedral coordination sites, instead of the BF₄ anions, with a Pd—O distance of 3.115 (2) Å. In [Pt(dms)₄](CF₃SO₃)₂ and [Pt(tx)₄](CF₃SO₃)₂·H₂O (Bugarcic et al., 1991), no close distances between the cations and the anions or the solvent molecules were found. For [Pd(dmso)₄](BF₄)₂·(CH₃)₂SO (dmso is dimethyl sulfoxide; Johnson et al., 1981), a Pd—O_solvent distance of 3.14 (3) Å was reported, but no distances to the anions that occupy the other side of the coordination plane were reported.

The geometry of a metal complex in the solid state is determined by the interplay between inter- and intramolecular forces. The Pd—S bonds within [Pd(dms)₄]²⁺ and [Pd(tx)₄]²⁺ experience different intermolecular forces, and their lengths are given in Table 3. The observed range in [Pd(dms)₄]²⁺ is 2.325 (8)–2.351 (6) Å, with a mean value of 2.338 (8) Å. The error of the mean is calculated as [Σ(x_i - M)²/(n-1)]^1/2, where M is the mean and n the number of distances. The corresponding range for [Pd(tx)₄]²⁺ is 2.329 (2)–2.341 (2) Å, with a mean of 2.334 (5) Å.

We have also studied the bonding at the extended Hückel level by calculating the reduced overlap population (ROP) in the Pd—S bonds using the program CACAO (Maelli & Proserpio, 1990) and the crystallographically observed geometries. No significant differences in neither the Pd—S bond lengths nor the ROP values are observed between the two title compounds (Table 3). The similarities in bonding are of course the result not only of similar bond distances but also of similar orientation of the ligands with respect to the coordination plane.

In conclusion, no significant differences in bonding between Pd^II and the ligands dimethylsulfide and 1,4-oxathiane have been observed, and it seems justified to calculate a mean value for the Pd—S distances of 2.337 (7) Å, where the error is calculated as given above. The mean value for the Pt—S distances in Table 3 is 2.319 (5) Å, and the difference of 0.018 (8) Å between the mean Pd—S and Pt—S distances is probably significant.

S2. Experimental

To prepare compound (I), HBF₄ (400 µl, 2.7 mmol) was added to a dms solution of Pd(OAc)₂ (OAc is acetate; 195 mg, 0.87 mmol). Yellow crystals precipitated immediately and the solution was stirred for 20 min. Recrystallization from dichloromethane gave yellow prismatic crystals of (I) suitable for X-ray diffraction. Compound (II) was prepared by adding an excess of 1,4-oxathiane to a solution of Pd(OAc)₂ (100 mg, 0.45 mmol) in dichloromethane. The solution was stirred at room temperature for 5 min before HBF₄ (150 µl, 1.0 mmol) was added. Pale yellow crystals of (II) precipitated immediately and the crystals were recrystallized from nitromethane.

S3. Refinement

H atoms were constrained to parent sites, with C—H = ? Please provide range for C—H and refined using a riding model, with U_iso(H) = 1.5U_eq(C) for CH₃ and 1.2U_eq(C) for CH₂. Are these the correct restraints? Please also provide details of C—H distances in CIF-format for addition to the archived CIF. The structure of (II) has one significant residual density peak of 2.561 e Å^-3 and one hole of -2.607 e Å^-3 in the final difference Fourier map, and these lie 1.07 and 0.87 Å from Pd, respectively. No high residual density peaks where found in the final difference Fourier map for (I).

Computing details

For both compounds, data collection: SMART (Siemens, 1995); cell refinement: SAINT (Siemens, 1995); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: DIAMOND (Brandenburg, 2000); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).

Figures

	Fig. 1. A view of the molecule of (I), showing the atom-numbering scheme and the position of the anions. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. A view of the molecule of (II), showing the atom-numbering scheme and the position of the anions. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Pd···F3'(1 + x, y, z; -1 - x, -y, -z) interactions have been omitted for clarity.

(I) Tetrakis(dimethyl sulfide)palladium(II) bis(tetrafluoroborate)

Crystal data

[Pd(C2H6S)4](BF4)2	F(000) = 528
Mr = 528.53	Dx = 1.736 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 8.4505 (17) Å	Cell parameters from 4803 reflections
b = 9.955 (2) Å	θ = 3–28°
c = 12.172 (2) Å	µ = 1.39 mm^−1
β = 98.99 (3)°	T = 293 K
V = 1011.4 (3) Å^3	Prism, pale yellow
Z = 2	0.3 × 0.1 × 0.1 mm

Data collection

Bruker SMART CCD area-detector diffractometer	3087 independent reflections
Radiation source: rotating anode	2408 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
Detector resolution: 512 pixels mm^-1	θmax = 31.6°, θmin = 2.7°
ω scans	h = −10→12
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996)	k = −14→12
Tmin = 0.595, Tmax = 0.831	l = −16→17
8129 measured 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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.127	H-atom parameters constrained
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0557P)^2 + 1.3665P] where P = (Fo^2 + 2Fc^2)/3
3087 reflections	(Δ/σ)max < 0.001
125 parameters	Δρmax = 0.77 e Å^−3
0 restraints	Δρmin = −0.54 e Å^−3

Special details

Experimental. The intensity data sets were collected at 293 K with a Bruker SMART CCD system using ω scans, -0.3° and 20 sec per frame for both data sets (Bruker, 1995). The detector distance was set to 4.0 cm. A rotating anode with Mo Kα radiation was used. Data are complete to 99.5% up to θ = 27.5° for (I) and to 98.8% up to θ = 27.9° for (II). Scattering factors, dispersion corrections and absorption coefficients were taken from International Tables for Crystallography, Vol. C. (1992), Tables 6.1.1.4, 4.2.6.8 and 4.2.4.2, respectively. All reflections were merged and integrated using SAINT (Bruker, 1995). Both structures were solved by direct methods and refined by full matrix least-square calculations on F² using SHELXTL 5.1 (Sheldrick, 1998). Non-H atoms were refined with anisotropic displacement parameters.

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.

# Selected torsion angles for compound (I) [Pd(dms)₄](BF₄)₂

-40.22 (0.30) S2_a - Pd - S1_a - C1 68.21 (0.27) S2_a - Pd - S1_a - C2 - 144.33 (0.28) S1_a - Pd - S2_a - C4 108.81 (0.26) S1_a - Pd - S2_a - C3 - 111.90 (0.62) S2'_b - Pd - S1'_b - C1 136.80 (0.53) S2'_b - Pd - S1'_b - C2 - 54.95 (0.67) S1'_b - Pd - S2'_b - C4 56.22 (0.54) S1'_b - Pd - S2'_b - C3

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	Occ. (<1)
Pd	0.0000	0.0000	0.0000	0.03938 (13)
S1	−0.10409 (17)	−0.05826 (13)	−0.18310 (9)	0.0606 (3)	0.875 (2)
S2	−0.17095 (16)	0.18541 (13)	−0.01339 (10)	0.0615 (3)	0.875 (2)
S1'	−0.1637 (12)	0.0755 (10)	−0.1614 (7)	0.062 (2)	0.125 (2)
S2'	−0.0984 (12)	0.1702 (9)	0.1014 (8)	0.065 (3)	0.125 (2)
C1	−0.3132 (8)	−0.0334 (8)	−0.2100 (6)	0.109 (2)
H1A	−0.3536	−0.0612	−0.2846	0.164*	0.875 (2)
H1B	−0.3367	0.0600	−0.2013	0.164*	0.875 (2)
H1C	−0.3632	−0.0856	−0.1586	0.164*	0.875 (2)
H1A'	−0.3744	−0.0008	−0.2752	0.164*	0.125 (2)
H1B'	−0.3790	−0.0512	−0.1537	0.164*	0.125 (2)
H1C'	−0.2660	−0.1213	−0.2269	0.164*	0.125 (2)
C2	−0.0379 (9)	0.0703 (7)	−0.2685 (4)	0.103 (2)
H2A	−0.0785	0.0522	−0.3452	0.155*	0.875 (2)
H2B	0.0771	0.0716	−0.2579	0.155*	0.875 (2)
H2C	−0.0767	0.1559	−0.2480	0.155*	0.875 (2)
H2A'	−0.0997	0.1007	−0.3386	0.155*	0.125 (2)
H2B'	−0.0038	−0.0197	−0.2776	0.155*	0.125 (2)
H2C'	0.0514	0.1282	−0.2491	0.155*	0.125 (2)
C3	−0.3180 (7)	0.1415 (8)	0.0744 (7)	0.108 (2)
H3A	−0.3892	0.2159	0.0781	0.163*	0.875 (2)
H3B	−0.2643	0.1204	0.1478	0.163*	0.875 (2)
H3C	−0.3783	0.0648	0.0437	0.163*	0.875 (2)
H3A'	−0.3632	0.2130	0.1150	0.163*	0.125 (2)
H3B'	−0.3331	0.0589	0.1016	0.163*	0.125 (2)
H3C'	−0.3472	0.1540	−0.0021	0.163*	0.125 (2)
C4	−0.0859 (9)	0.3274 (5)	0.0593 (6)	0.105 (2)
H4A	−0.1624	0.3995	0.0513	0.157*	0.875 (2)
H4B	0.0078	0.3547	0.0296	0.157*	0.875 (2)
H4C	−0.0568	0.3057	0.1367	0.157*	0.875 (2)
H4A'	−0.1323	0.3842	0.1087	0.157*	0.125 (2)
H4B'	−0.1466	0.3343	−0.0146	0.157*	0.125 (2)
H4C'	0.0225	0.3485	0.0586	0.157*	0.125 (2)
B	0.2931 (9)	0.2880 (8)	−0.0900 (5)	0.0797 (17)
F1	0.1615 (8)	0.3416 (6)	−0.1449 (4)	0.177 (3)
F2	0.2723 (7)	0.2139 (7)	−0.0047 (5)	0.180 (3)
F3	0.3694 (9)	0.2169 (8)	−0.1559 (5)	0.208 (3)
F4	0.3905 (11)	0.3804 (8)	−0.0492 (7)	0.261 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pd	0.0438 (2)	0.03826 (19)	0.03665 (18)	0.00101 (14)	0.00817 (13)	−0.00176 (13)
S1	0.0836 (9)	0.0531 (7)	0.0418 (5)	0.0047 (6)	0.0000 (5)	−0.0062 (5)
S2	0.0708 (8)	0.0587 (7)	0.0542 (6)	0.0221 (6)	0.0069 (5)	−0.0032 (5)
S1'	0.075 (6)	0.060 (5)	0.050 (4)	0.009 (4)	0.002 (4)	0.005 (4)
S2'	0.073 (5)	0.058 (5)	0.066 (5)	0.012 (4)	0.016 (4)	−0.018 (4)
C1	0.086 (4)	0.140 (6)	0.090 (4)	−0.021 (4)	−0.025 (4)	−0.013 (4)
C2	0.161 (7)	0.103 (5)	0.050 (3)	−0.005 (5)	0.030 (3)	0.014 (3)
C3	0.069 (3)	0.130 (6)	0.134 (6)	0.016 (4)	0.039 (4)	−0.021 (5)
C4	0.143 (6)	0.046 (3)	0.131 (6)	0.007 (3)	0.040 (5)	−0.010 (3)
B	0.094 (4)	0.088 (4)	0.057 (3)	−0.023 (4)	0.011 (3)	0.007 (3)
F1	0.200 (6)	0.196 (6)	0.119 (4)	0.093 (5)	−0.026 (4)	−0.005 (4)
F2	0.129 (4)	0.234 (7)	0.186 (5)	−0.002 (4)	0.055 (4)	0.118 (5)
F3	0.229 (7)	0.269 (9)	0.130 (4)	0.110 (6)	0.039 (4)	−0.005 (5)
F4	0.351 (11)	0.197 (7)	0.207 (7)	−0.163 (8)	−0.038 (7)	0.008 (6)

Geometric parameters (Å, º)

Pd—S1	2.3375 (12)	S2—C3	1.814 (7)
Pd—S1^i	2.3375 (12)	S2—C4	1.761 (6)
Pd—S2^i	2.3338 (12)	S1'—C1	1.700 (12)
Pd—S2	2.3338 (12)	S1'—C2	1.807 (12)
Pd—S1'^i	2.343 (8)	S2'—C3	1.855 (12)
Pd—S1'	2.343 (8)	S2'—C4	1.655 (11)
Pd—S2'	2.325 (8)	B—F4	1.281 (8)
Pd—S2'^i	2.325 (8)	B—F2	1.308 (7)
S1—C1	1.764 (7)	B—F3	1.313 (9)
S1—C2	1.792 (6)	B—F1	1.317 (8)
S1—Pd—S1^i	180.00 (2)	S1—Pd—S1'	36.4 (2)
S1—Pd—S1'^i	143.6 (2)	S1^i—Pd—S1'	143.6 (2)
S1^i—Pd—S1'^i	36.4 (2)	S1'^i—Pd—S1'	180.0 (4)
S1^i—Pd—S2	90.40 (5)	Pd—S1—C1	111.0 (3)
S1—Pd—S2	89.60 (5)	Pd—S1—C2	105.7 (2)
S1'—Pd—S2'^i	90.1 (3)	Pd—S2—C3	104.0 (2)
S1'^i—Pd—S2'^i	89.9 (3)	Pd—S2—C4	113.6 (2)
S2'—Pd—S2'^i	180.0 (4)	Pd—S1'—C1	113.3 (5)
S2'—Pd—S2^i	143.9 (2)	Pd—S1'—C2	105.0 (5)
S2'^i—Pd—S2^i	36.1 (2)	Pd—S2'—C3	103.0 (5)
S2'—Pd—S2	36.1 (2)	Pd—S2'—C4	118.6 (6)
S2'^i—Pd—S2	143.9 (2)	C1—S1—C2	100.8 (4)
S2^i—Pd—S2	180.00 (5)	C3—S2—C4	99.3 (4)
S2'—Pd—S1	125.1 (2)	C1—S1'—C2	102.7 (6)
S2'^i—Pd—S1	54.9 (2)	C3—S2'—C4	101.6 (6)
S2'—Pd—S1^i	54.9 (2)	S1'—C1—S1	49.9 (4)
S2'^i—Pd—S1^i	125.1 (2)	S1—C2—S1'	48.0 (3)
S2^i—Pd—S1^i	89.60 (5)	S2—C3—S2'	46.3 (3)
S2—Pd—S1^i	90.40 (5)	S2'—C4—S2	49.9 (4)
S2^i—Pd—S1'^i	53.8 (2)	F4—B—F2	104.8 (7)
S2—Pd—S1'^i	126.2 (2)	F4—B—F3	106.1 (8)
S2'—Pd—S1'	89.9 (3)	F2—B—F3	108.7 (7)
S2'^i—Pd—S1'	90.1 (3)	F4—B—F1	110.3 (8)
S2^i—Pd—S1'	126.2 (2)	F2—B—F1	115.1 (7)
S2—Pd—S1'	53.8 (2)	F3—B—F1	111.4 (6)

Symmetry code: (i) −x, −y, −z.

(II) tetrakis(1,4-oxathiane-S)palladium(II) bis(tetrafluoroborate)

Crystal data

[Pd(C4H8OS)4](BF4)2	Z = 1
Mr = 696.68	F(000) = 352
Triclinic, P1	Dx = 1.722 Mg m^−3
a = 8.8804 (18) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.5397 (19) Å	Cell parameters from 2469 reflections
c = 9.6999 (19) Å	θ = 4–26°
α = 94.11 (3)°	µ = 1.08 mm^−1
β = 114.12 (3)°	T = 293 K
γ = 111.79 (3)°	Prism, yellow
V = 671.8 (2) Å^3	0.20 × 0.14 × 0.12 mm

Data collection

Bruker SMART CCD area-detector diffractometer	3185 independent reflections
Radiation source: rotating anode	2080 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.050
Detector resolution: 512 pixels mm^-1	θmax = 27.9°, θmin = 2.4°
ω scans	h = −11→11
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996)	k = −11→12
Tmin = 0.813, Tmax = 0.882	l = −12→10
4856 measured 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)] = 0.080	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.203	H-atom parameters constrained
S = 0.96	w = 1/[σ^2(Fo^2) + (0.1175P)^2] where P = (Fo^2 + 2Fc^2)/3
3185 reflections	(Δ/σ)max < 0.001
188 parameters	Δρmax = 2.56 e Å^−3
0 restraints	Δρmin = −2.61 e Å^−3

Special details

Experimental. The intensity data sets were collected at 293 K with a Bruker SMART CCD system using ω scans, -0.3° and 20 sec per frame for both data sets (Bruker, 1995). The detector distance was set to 4.0 cm. A rotating anode with Mo Kα radiation was used. Data are complete to 99.5% up to θ = 27.5° for (I) and to 98.8% up to θ = 27.9° for (II). Scattering factors, dispersion corrections and absorption coefficients were taken from International Tables for Crystallography, Vol. C. (1992), Tables 6.1.1.4, 4.2.6.8 and 4.2.4.2, respectively. All reflections were merged and integrated using SAINT (Bruker, 1995). Both structures were solved by direct methods and refined by full matrix least-square calculations on F² using SHELXTL 5.1 (Sheldrick, 1998). Non-H atoms were refined with anisotropic displacement parameters.

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.

# Selected torsion angles for compound [Pd(tx)₄](BF₄)₂, (II)

-137.21 (0.34) S2 - Pd - S1 - C1 116.45 (1/4) S2 - Pd - S1 - C3 48.35 (0.32) S1 - Pd - S2 - C7 - 58.25 (0.28) S1 - Pd - S2 - C5 - 52.53 (0.73) C3 - S1 - C1 - C2 - 165.75 (0.59) Pd - S1 - C1 - C2 - 64.91 (0.98) C4 - O1 - C2 - C1 61.73 (0.99) S1 - C1 - C2 - O1 53.10 (0.56) C1 - S1 - C3 - C4 168.68 (0.43) Pd - S1 - C3 - C4 66.00 (0.89) C2 - O1 - C4 - C3 - 63.18 (0.78) S1 - C3 - C4 - O1 51.76 (0.65) C7 - S2 - C5 - C6 167.53 (1/2) Pd - S2 - C5 - C6 68.22 (0.91) C8 - O2 - C6 - C5 - 62.11 (0.83) S2 - C5 - C6 - O2 - 51.24 (0.68) C5 - S2 - C7 - C8 - 162.61 (0.53) Pd - S2 - C7 - C8 - 68.21 (0.94) C6 - O2 - C8 - C7

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	Occ. (<1)
Pd	0.0000	0.0000	0.0000	0.0389 (3)
S1	0.1223 (3)	−0.12129 (19)	0.18864 (18)	0.0434 (4)
S2	−0.0004 (3)	0.1677 (2)	0.18654 (18)	0.0453 (5)
O1	0.1913 (9)	−0.4185 (7)	0.2135 (7)	0.0646 (15)
O2	0.0678 (9)	0.2047 (7)	0.5288 (6)	0.0673 (17)
C1	0.3008 (11)	−0.1557 (11)	0.1718 (11)	0.061 (2)
H1A	0.2616	−0.1989	0.0627	0.074*
H1B	0.4106	−0.0577	0.2104	0.074*
C2	0.3429 (14)	−0.2699 (13)	0.2665 (12)	0.076 (3)
H2A	0.4438	−0.2831	0.2612	0.091*
H2B	0.3825	−0.2252	0.3753	0.091*
C3	−0.0429 (10)	−0.3229 (8)	0.1328 (8)	0.0461 (16)
H3A	−0.1473	−0.3286	0.1462	0.055*
H3B	−0.0868	−0.3692	0.0233	0.055*
C4	0.0455 (13)	−0.4120 (9)	0.2328 (9)	0.057 (2)
H4A	0.0908	−0.3632	0.3419	0.069*
H4B	−0.0471	−0.5179	0.2077	0.069*
C5	−0.1404 (11)	0.0437 (9)	0.2626 (8)	0.0507 (18)
H5A	−0.2687	−0.0030	0.1842	0.061*
H5B	−0.1054	−0.0400	0.2873	0.061*
C6	−0.1142 (12)	0.1405 (12)	0.4094 (9)	0.063 (2)
H6A	−0.1485	0.2244	0.3839	0.076*
H6B	−0.1947	0.0749	0.4463	0.076*
C7	0.2141 (12)	0.2538 (10)	0.3612 (9)	0.060 (2)
H7A	0.2585	0.1757	0.3878	0.072*
H7B	0.3040	0.3369	0.3449	0.072*
C8	0.1905 (13)	0.3200 (10)	0.4944 (9)	0.066 (2)
H8A	0.3092	0.3717	0.5874	0.079*
H8B	0.1460	0.3979	0.4666	0.079*
B1	−0.4746 (15)	0.2873 (13)	0.1682 (14)	0.070 (3)
F1	−0.4548 (13)	0.2388 (15)	0.3108 (11)	0.157 (4)
F2	−0.646 (2)	0.251 (3)	0.094 (2)	0.108 (8)	0.51 (2)
F2'	−0.543 (4)	0.398 (3)	0.174 (2)	0.134 (10)	0.49 (2)
F3	−0.447 (3)	0.172 (3)	0.0910 (16)	0.121 (8)	0.51 (2)
F3'	−0.607 (5)	0.172 (3)	0.069 (4)	0.23 (2)	0.49 (2)
F4	−0.348 (4)	0.412 (3)	0.216 (3)	0.191 (18)	0.51 (2)
F4'	−0.325 (4)	0.350 (6)	0.168 (6)	0.24 (2)	0.49 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pd	0.0707 (6)	0.0420 (4)	0.0305 (4)	0.0368 (4)	0.0350 (4)	0.0191 (3)
S1	0.0724 (12)	0.0431 (9)	0.0329 (8)	0.0363 (9)	0.0297 (8)	0.0181 (7)
S2	0.0823 (13)	0.0502 (10)	0.0344 (8)	0.0455 (10)	0.0384 (9)	0.0216 (7)
O1	0.093 (4)	0.071 (4)	0.067 (4)	0.062 (4)	0.045 (3)	0.031 (3)
O2	0.118 (5)	0.083 (4)	0.034 (3)	0.066 (4)	0.043 (3)	0.029 (3)
C1	0.059 (5)	0.079 (6)	0.061 (5)	0.040 (4)	0.029 (4)	0.030 (4)
C2	0.079 (6)	0.102 (8)	0.074 (6)	0.067 (6)	0.034 (5)	0.039 (6)
C3	0.069 (5)	0.045 (4)	0.049 (4)	0.034 (4)	0.040 (4)	0.021 (3)
C4	0.101 (6)	0.053 (4)	0.058 (5)	0.052 (4)	0.054 (5)	0.031 (4)
C5	0.063 (5)	0.070 (5)	0.038 (4)	0.038 (4)	0.033 (3)	0.016 (3)
C6	0.090 (6)	0.095 (6)	0.046 (4)	0.059 (5)	0.050 (4)	0.033 (4)
C7	0.077 (5)	0.050 (5)	0.054 (5)	0.028 (4)	0.032 (4)	0.004 (3)
C8	0.095 (6)	0.059 (5)	0.039 (4)	0.045 (5)	0.020 (4)	−0.001 (4)
B1	0.055 (7)	0.059 (7)	0.077 (7)	0.010 (6)	0.031 (5)	−0.004 (5)
F1	0.179 (8)	0.258 (12)	0.120 (7)	0.149 (8)	0.093 (6)	0.088 (7)
F2	0.063 (10)	0.16 (2)	0.114 (14)	0.055 (14)	0.045 (10)	0.038 (15)
F2'	0.17 (2)	0.15 (2)	0.112 (14)	0.111 (19)	0.053 (13)	0.038 (13)
F3	0.183 (19)	0.18 (2)	0.065 (8)	0.128 (17)	0.070 (10)	0.032 (9)
F3'	0.21 (4)	0.12 (2)	0.22 (3)	−0.02 (2)	0.07 (2)	−0.09 (2)
F4	0.15 (2)	0.119 (16)	0.19 (2)	−0.073 (16)	0.117 (18)	−0.086 (15)
F4'	0.19 (3)	0.32 (5)	0.44 (6)	0.18 (3)	0.26 (4)	0.27 (5)

Geometric parameters (Å, º)

Pd—S1	2.3406 (17)	C7—C8	1.522 (11)
Pd—S1^i	2.3406 (17)	B1—F4	1.180 (19)
Pd—S2^i	2.3293 (17)	B1—F3'	1.22 (2)
Pd—S2	2.3293 (17)	B1—F4'	1.24 (2)
S1—C1	1.799 (9)	B1—F2	1.278 (18)
S1—C3	1.803 (7)	B1—F2'	1.41 (2)
S2—C5	1.809 (7)	B1—F3	1.436 (19)
S2—C7	1.782 (8)	B1—F1	1.453 (14)
O1—C2	1.414 (12)	F2—F3'	0.99 (4)
O1—C4	1.403 (10)	F2—F2'	1.31 (3)
O2—C6	1.401 (10)	F2'—F4	1.56 (3)
O2—C8	1.403 (11)	F3—F3'	1.35 (4)
C1—C2	1.529 (12)	F3—F4'	1.55 (5)
C3—C4	1.507 (10)	F4—F4'	0.86 (4)
C5—C6	1.523 (10)
S2^i—Pd—S2	180.00 (8)	F2—B1—F2'	58.1 (13)
S1^i—Pd—S2	89.48 (6)	F4—B1—F3	111.8 (18)
S1—Pd—S2	90.52 (6)	F3'—B1—F3	61 (2)
S1^i—Pd—S2^i	90.52 (6)	F4'—B1—F3	70 (2)
S2—Pd—S1^i	89.48 (6)	F2—B1—F3	106.2 (16)
S1—Pd—S1^i	180.00 (9)	F2'—B1—F3	154.8 (14)
Pd—S1—C1	111.3 (3)	F4—B1—F1	102.6 (16)
Pd—S1—C3	108.4 (2)	F3'—B1—F1	102 (2)
Pd—S2—C5	106.2 (3)	F4'—B1—F1	112 (2)
Pd—S2—C7	111.7 (3)	F2—B1—F1	103.2 (11)
C1—S1—C3	97.7 (4)	F2'—B1—F1	102.6 (12)
C5—S2—C7	98.7 (4)	F3—B1—F1	100.3 (12)
C2—O1—C4	112.6 (7)	F3'—F2—B1	64 (2)
C6—O2—C8	113.0 (6)	F3'—F2—F2'	128 (3)
C2—C1—S1	109.7 (6)	B1—F2—F2'	65.9 (13)
O1—C2—C1	113.4 (7)	F2—F2'—B1	56.0 (11)
C4—C3—S1	109.6 (6)	F2—F2'—F4	101.1 (16)
O1—C4—C3	113.8 (6)	B1—F2'—F4	46.6 (11)
C6—C5—S2	109.6 (6)	F3'—F3—B1	51.7 (11)
O2—C6—C5	111.8 (7)	F3'—F3—F4'	96.8 (17)
C8—C7—S2	109.7 (6)	B1—F3—F4'	48.9 (11)
O2—C8—C7	112.7 (7)	F2—F3'—B1	69.9 (17)
F4—B1—F3'	156 (2)	F2—F3'—F3	136 (3)
F4—B1—F4'	42 (2)	B1—F3'—F3	68 (2)
F3'—B1—F4'	124 (3)	F4'—F4—B1	73 (3)
F4—B1—F2	129 (2)	F4'—F4—F2'	126 (4)
F3'—B1—F2	47 (2)	B1—F4—F2'	60.0 (14)
F4'—B1—F2	145 (2)	F4—F4'—B1	65.5 (19)
F4—B1—F2'	73 (2)	F4—F4'—F3	126 (3)
F3'—B1—F2'	104 (2)	B1—F4'—F3	60.8 (18)
F4'—B1—F2'	110 (2)

Symmetry code: (i) −x, −y, −z.