A cyclic dipalladium compound formed by concomitant N–C coupling and [2+3]-cyclo­addition: bis{μ-1-[4-(carbodiimido)­phenyl]­tetrazolato-κ²N:C⁵}bis­[bis­(tri­methyl­phosphine-κP)­palladium(II)]

The title compound, [Pd₂(C₈H₄N₆)₂(C₃H₉P)₄], was prepared by treating Pd(PMe₃)₂(N₃)₂ with 1,4-phenyl­ene diisocyanide [C₆H₄(NC)₂]. This compound, a cyclic dimer, was formed by concomitant N—C coupling and [2 + 3]-cyclo­addition. Around the square-planar Pd atom, the carbodi­imide moiety and the tetrazolate ring are mutually trans. The N atom of the carbodi­imide moiety is bonded to the Pd center, and the five-membered tetrazolate ring is coordinated to the Pd atoms through the C atom. The molecule is located on a center of symmetry.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.035
• wR factor = 0.094
• Data-to-parameter ratio = 16.2

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT242_ALERT_2_A Check Low    U(eq) as Compared to Neighbors  for         P2

Author Response: One trimethylphospine ligand is slightly disordered. Anisotropic refinements applying several possible site occupation fators were unstable, and that is why the thermal parameters of the carbon atoms (C12--C14) in that phosphine ligand are relatively large compared with those in the other phosphine ligand.

Alert level B
PLAT027_ALERT_3_B _diffrn_reflns_theta_full (too) Low ............      24.99 Deg.

Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       3.12 Ratio
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Pd1    -   C1      ..       5.02 su
PLAT241_ALERT_2_C Check High   U(eq) as Compared to Neighbors  for         C4
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors  for         P1

Author Response: One trimethylphospine ligand is slightly disordered. Anisotropic refinements applying several possible site occupation fators were unstable, and that is why the thermal parameters of the carbon atoms (C12--C14) in that phosphine ligand are relatively large compared with those in the other phosphine ligand.

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   5 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
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: XSCANS (Siemens, 1995); cell refinement: XSCANS; data reduction: SHELXTL (Siemens, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

bis{µ-1-[4-(carbodiimido)phenyl]tetrazolato-κ²N:C⁵} bis[bis(trimethylphosphine-κP)palladium(II)]

Crystal data

[Pd2(C8H4N6)2(C3H9P)4]	Z = 1
Mr = 885.43	F(000) = 448
Triclinic, P1	Dx = 1.518 Mg m^−3
a = 8.842 (3) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.519 (3) Å	Cell parameters from 26 reflections
c = 11.996 (3) Å	θ = 5.1–12.5°
α = 99.095 (19)°	µ = 1.13 mm^−1
β = 103.42 (2)°	T = 293 K
γ = 90.85 (2)°	Block, orange
V = 968.5 (5) Å^3	0.50 × 0.42 × 0.20 mm

Data collection

Siemens P4 diffractometer	3039 reflections with I > 2σ(I)
Radiation source: sealed tube	Rint = 0.021
Graphite monochromator	θmax = 25.0°, θmin = 1.8°
ω scans	h = 0→10
Absorption correction: empirical (using intensity measurements) (North et al., 1968)	k = −11→11
Tmin = 0.574, Tmax = 0.798	l = −14→13
3615 measured reflections	3 standard reflections every 97 reflections
3374 independent reflections	intensity decay: none

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.094	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0632P)^2 + 0.2618P] where P = (Fo^2 + 2Fc^2)/3
3374 reflections	(Δ/σ)max = 0.001
208 parameters	Δρmax = 0.66 e Å^−3
0 restraints	Δρmin = −0.50 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	0.69364 (3)	0.89012 (2)	0.684937 (19)	0.03877 (12)
P1	0.86814 (11)	0.71478 (10)	0.65981 (8)	0.0497 (2)
P2	0.52022 (11)	1.06752 (10)	0.71136 (8)	0.0493 (2)
N1	0.4193 (4)	0.6818 (3)	0.6233 (3)	0.0593 (8)
N2	0.3520 (4)	0.5830 (4)	0.6699 (3)	0.0675 (9)
N3	0.4299 (4)	0.5816 (4)	0.7766 (3)	0.0672 (9)
N4	0.5512 (3)	0.6819 (3)	0.7991 (3)	0.0494 (7)
N5	0.8589 (4)	1.0376 (3)	0.6725 (3)	0.0571 (7)
N6	1.0090 (5)	1.2573 (4)	0.7705 (3)	0.0735 (10)
C1	0.5439 (4)	0.7435 (3)	0.7030 (3)	0.0464 (7)
C2	0.6636 (4)	0.7005 (3)	0.9077 (3)	0.0474 (8)
C3	0.6839 (5)	0.5913 (4)	0.9737 (4)	0.0711 (12)
H3	0.6237	0.5065	0.9467	0.085*
C4	0.7915 (6)	0.6077 (4)	1.0776 (4)	0.0794 (14)
H4	0.8032	0.5329	1.1198	0.095*
C5	0.8845 (5)	0.7330 (4)	1.1226 (3)	0.0553 (9)
C6	0.8630 (5)	0.8417 (4)	1.0558 (3)	0.0535 (9)
H6	0.9240	0.9261	1.0817	0.064*
C7	0.7528 (5)	0.8257 (4)	0.9522 (3)	0.0553 (9)
H7	0.7380	0.9014	0.9111	0.066*
C8	0.9326 (4)	1.1400 (4)	0.7241 (3)	0.0525 (8)
C9	0.8030 (6)	0.5303 (4)	0.6480 (5)	0.0768 (13)
H9A	0.7609	0.5195	0.7133	0.092*
H9B	0.8895	0.4707	0.6471	0.092*
H9C	0.7242	0.5030	0.5774	0.092*
C10	1.0392 (5)	0.7415 (6)	0.7802 (4)	0.0756 (12)
H10A	1.0084	0.7388	0.8515	0.091*
H10B	1.0904	0.8323	0.7839	0.091*
H10C	1.1093	0.6674	0.7688	0.091*
C11	0.9429 (6)	0.7205 (5)	0.5329 (4)	0.0775 (13)
H11A	0.9806	0.8159	0.5339	0.093*
H11B	0.8614	0.6912	0.4643	0.093*
H11C	1.0266	0.6574	0.5330	0.093*
C12	0.5553 (9)	1.1560 (9)	0.8590 (5)	0.145 (3)
H12A	0.5424	1.0883	0.9079	0.174*
H12B	0.4827	1.2292	0.8649	0.174*
H12C	0.6596	1.1979	0.8832	0.174*
C13	0.3158 (6)	1.0171 (6)	0.6672 (7)	0.111 (2)
H13A	0.2898	0.9729	0.5870	0.133*
H13B	0.2570	1.1003	0.6768	0.133*
H13C	0.2914	0.9511	0.7141	0.133*
C14	0.5331 (7)	1.2117 (6)	0.6326 (7)	0.106 (2)
H14A	0.5138	1.1749	0.5511	0.128*
H14B	0.6353	1.2578	0.6589	0.128*
H14C	0.4570	1.2792	0.6460	0.128*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pd1	0.04284 (17)	0.03285 (16)	0.04123 (16)	0.00057 (10)	0.01206 (11)	0.00502 (10)
P1	0.0526 (5)	0.0447 (5)	0.0551 (5)	0.0115 (4)	0.0182 (4)	0.0091 (4)
P2	0.0540 (5)	0.0398 (5)	0.0564 (5)	0.0080 (4)	0.0198 (4)	0.0043 (4)
N1	0.0543 (18)	0.0523 (18)	0.0639 (19)	−0.0095 (14)	0.0049 (15)	0.0022 (14)
N2	0.0559 (19)	0.060 (2)	0.080 (2)	−0.0145 (16)	0.0080 (17)	0.0046 (17)
N3	0.062 (2)	0.0547 (19)	0.086 (2)	−0.0179 (16)	0.0230 (19)	0.0092 (17)
N4	0.0505 (16)	0.0377 (14)	0.0610 (17)	−0.0099 (12)	0.0195 (13)	0.0026 (12)
N5	0.0537 (18)	0.0533 (18)	0.0681 (19)	−0.0030 (15)	0.0147 (15)	0.0213 (15)
N6	0.085 (2)	0.0473 (18)	0.080 (2)	−0.0100 (17)	−0.0055 (19)	0.0271 (16)
C1	0.0496 (19)	0.0374 (17)	0.0515 (18)	0.0020 (14)	0.0132 (15)	0.0034 (14)
C2	0.0559 (19)	0.0378 (17)	0.0537 (19)	−0.0017 (14)	0.0226 (16)	0.0086 (14)
C3	0.081 (3)	0.0355 (19)	0.091 (3)	−0.0127 (18)	0.007 (2)	0.0181 (19)
C4	0.097 (3)	0.040 (2)	0.096 (3)	−0.009 (2)	−0.002 (3)	0.033 (2)
C5	0.066 (2)	0.0402 (18)	0.063 (2)	0.0005 (16)	0.0146 (18)	0.0165 (16)
C6	0.076 (2)	0.0349 (17)	0.0507 (19)	−0.0119 (16)	0.0169 (17)	0.0079 (14)
C7	0.082 (3)	0.0371 (17)	0.0500 (19)	−0.0074 (17)	0.0200 (18)	0.0117 (14)
C8	0.051 (2)	0.053 (2)	0.061 (2)	0.0070 (17)	0.0156 (17)	0.0279 (17)
C9	0.096 (3)	0.043 (2)	0.097 (3)	0.015 (2)	0.037 (3)	0.005 (2)
C10	0.057 (2)	0.092 (3)	0.075 (3)	0.021 (2)	0.007 (2)	0.016 (2)
C11	0.085 (3)	0.087 (3)	0.076 (3)	0.028 (3)	0.044 (3)	0.021 (2)
C12	0.169 (7)	0.174 (7)	0.072 (4)	0.095 (6)	0.017 (4)	−0.028 (4)
C13	0.060 (3)	0.074 (3)	0.198 (7)	0.011 (3)	0.034 (4)	0.017 (4)
C14	0.102 (4)	0.069 (3)	0.174 (6)	0.032 (3)	0.059 (4)	0.057 (4)

Geometric parameters (Å, º)

Pd1—C1	1.980 (3)	C4—H4	0.9300
Pd1—N5	2.058 (3)	C5—N6^i	1.393 (5)
Pd1—P1	2.3219 (11)	C5—C6	1.395 (5)
Pd1—P2	2.3318 (11)	C6—C7	1.375 (5)
P1—C11	1.802 (4)	C6—H6	0.9300
P1—C9	1.814 (4)	C7—H7	0.9300
P1—C10	1.816 (4)	C9—H9A	0.9600
P2—C12	1.791 (5)	C9—H9B	0.9600
P2—C13	1.797 (5)	C9—H9C	0.9600
P2—C14	1.801 (5)	C10—H10A	0.9600
N1—C1	1.336 (5)	C10—H10B	0.9600
N1—N2	1.361 (5)	C10—H10C	0.9600
N2—N3	1.308 (5)	C11—H11A	0.9600
N3—N4	1.375 (4)	C11—H11B	0.9600
N4—C1	1.362 (4)	C11—H11C	0.9600
N4—C2	1.428 (5)	C12—H12A	0.9600
N5—C8	1.166 (5)	C12—H12B	0.9600
N6—C8	1.272 (5)	C12—H12C	0.9600
N6—C5^i	1.393 (5)	C13—H13A	0.9600
C2—C7	1.380 (5)	C13—H13B	0.9600
C2—C3	1.392 (5)	C13—H13C	0.9600
C3—C4	1.367 (6)	C14—H14A	0.9600
C3—H3	0.9300	C14—H14B	0.9600
C4—C5	1.397 (5)	C14—H14C	0.9600
C1—Pd1—N5	176.78 (13)	C7—C6—H6	119.5
C1—Pd1—P1	89.50 (10)	C5—C6—H6	119.5
N5—Pd1—P1	88.28 (10)	C6—C7—C2	121.8 (3)
C1—Pd1—P2	90.86 (10)	C6—C7—H7	119.1
N5—Pd1—P2	91.35 (10)	C2—C7—H7	119.1
P1—Pd1—P2	179.48 (3)	N5—C8—N6	173.9 (4)
C11—P1—C9	105.0 (2)	P1—C9—H9A	109.5
C11—P1—C10	104.6 (2)	P1—C9—H9B	109.5
C9—P1—C10	104.6 (2)	H9A—C9—H9B	109.5
C11—P1—Pd1	112.42 (15)	P1—C9—H9C	109.5
C9—P1—Pd1	118.37 (16)	H9A—C9—H9C	109.5
C10—P1—Pd1	110.68 (16)	H9B—C9—H9C	109.5
C12—P2—C13	106.1 (4)	P1—C10—H10A	109.5
C12—P2—C14	103.0 (4)	P1—C10—H10B	109.5
C13—P2—C14	101.9 (3)	H10A—C10—H10B	109.5
C12—P2—Pd1	112.7 (2)	P1—C10—H10C	109.5
C13—P2—Pd1	117.55 (19)	H10A—C10—H10C	109.5
C14—P2—Pd1	114.05 (19)	H10B—C10—H10C	109.5
C1—N1—N2	108.4 (3)	P1—C11—H11A	109.5
N3—N2—N1	109.9 (3)	P1—C11—H11B	109.5
N2—N3—N4	106.4 (3)	H11A—C11—H11B	109.5
C1—N4—N3	109.1 (3)	P1—C11—H11C	109.5
C1—N4—C2	130.9 (3)	H11A—C11—H11C	109.5
N3—N4—C2	119.9 (3)	H11B—C11—H11C	109.5
C8—N5—Pd1	142.0 (3)	P2—C12—H12A	109.5
C8—N6—C5^i	119.7 (3)	P2—C12—H12B	109.5
N1—C1—N4	106.2 (3)	H12A—C12—H12B	109.5
N1—C1—Pd1	127.4 (3)	P2—C12—H12C	109.5
N4—C1—Pd1	126.3 (3)	H12A—C12—H12C	109.5
C7—C2—C3	117.7 (4)	H12B—C12—H12C	109.5
C7—C2—N4	122.2 (3)	P2—C13—H13A	109.5
C3—C2—N4	120.1 (3)	P2—C13—H13B	109.5
C4—C3—C2	120.6 (4)	H13A—C13—H13B	109.5
C4—C3—H3	119.7	P2—C13—H13C	109.5
C2—C3—H3	119.7	H13A—C13—H13C	109.5
C3—C4—C5	122.2 (3)	H13B—C13—H13C	109.5
C3—C4—H4	118.9	P2—C14—H14A	109.5
C5—C4—H4	118.9	P2—C14—H14B	109.5
N6^i—C5—C6	124.2 (3)	H14A—C14—H14B	109.5
N6^i—C5—C4	119.1 (3)	P2—C14—H14C	109.5
C6—C5—C4	116.7 (4)	H14A—C14—H14C	109.5
C7—C6—C5	121.0 (3)	H14B—C14—H14C	109.5

Symmetry code: (i) −x+2, −y+2, −z+2.