Tetra­pyridinecopper(I) hexa­fluorido­phosphate(V)

The crystal structure of the title compound, [Cu(C₅H₅N)₄]PF₆, consists of discrete [Cu(C₅H₅N)₄]⁺ and PF₆^- ions. Both the cations and the anions are located on axes. The pyridine ligands are bonded to the Cu⁺ ion in an almost perfectly tetra­hedral coordination geometry, with Cu-N = 2.061 (3) Å and N-Cu-N angles of 110.00 (9) and 108.42 (17)°.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.044
• wR factor = 0.118
• Data-to-parameter ratio = 16.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT244_ALERT_4_C Low   'Solvent' Ueq as Compared to Neighbors for         P1
PLAT341_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          7

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           26.96
           From the CIF: _reflns_number_total               1212
           Count of symmetry unique reflns          661
           Completeness (_total/calc)            183.36%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       551
           Fraction of Friedel pairs measured     0.834
           Are heavy atom types Z>Si present        yes
PLAT794_ALERT_5_G Check Predicted Bond Valency for Cu1         (1)       0.92
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

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

   0 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
   2 ALERT type 3 Indicator that the structure quality may be low
   2 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 discrete tetrakis(pyridine)copper(I) and hexafluorophosphate(V) ions. The copper and phosphorus atoms are placed in 2a and 2c special positions of the space group respectively. The coordination of copper is almost perfectly tetrahedral with N—Cu—N angles 110.00 (9)° and 108.42 (17)°. The planes of the pyridine rings are at angles of 79.38° and 65.93°.

The hexafluorophosphate anions are octahedral and slightly elongated along z axes with F—P—F angles in the range 89.4 (3)° - 90.6 (3)° and P—F bond lengths 1.527 (4) Å and 1.553 (5) Å.

The shortest intermolecular distance is a C—H···F contact of 3.445 Å

Related literature

The only previously described structure containing tetrakis(pyridine)copper(I) cations is the perchlorate salt described by Nilsson & Oskarsson (1981, 1982). It crystallized in the same space group as the title compound with analogous placement of the ions. The Cu atom was almost perfectly tetrahedrally coordinated.

S2. Experimental

The title compound was obtained unintentionally while attempting to crystallize a coordination compound of copper(I) with a bisoxazoline ligand. Tetrakis(acetonitrile)copper(I) hexafluorophosphate(V) (10 mg) and bisoxazoline (20 mg) were dissolved in a mixture of pyridine and toluene (10 ml, 1:1) and heated to boiling. The resulting solution was cooled to room temperature and left to slowly evaporate. Colourless crystals of (I) were obtained after 4 days.

S3. Refinement

All H atoms were placed geometrically and included in the refinement in the riding-model approximation, with C—H distances 0.93 with U_iso = 1.2U_eq of the carrier atom.

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2003); cell refinement: CrysAlis RED (Oxford Diffraction, 2003); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999) and PARST95 (Nardelli, 1995).

Figures

	Fig. 1. View of (I) with the atom labeling scheme. Displacement ellipsoids are shown at 20% probability. Hydrogen atoms are shown as spheres of arbitrary radius.
	Fig. 2. Crystal packing of (I) viewed along the z axis.

Tetrapyridinecopper(I) hexafluoridophosphate(V)

Crystal data

[Cu(C5H5N)4]PF6	Dx = 1.547 Mg m^−3
Mr = 524.91	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4	Cell parameters from 1485 reflections
Hall symbol: I -4	θ = 4.6–32.0°
a = 12.600 (2) Å	µ = 1.10 mm^−1
c = 7.0983 (14) Å	T = 295 K
V = 1126.9 (3) Å^3	Prism, colourless
Z = 2	0.39 × 0.19 × 0.14 mm
F(000) = 532

Data collection

Oxford Diffraction Xcalibur CCD area-detector diffractometer	1212 independent reflections
Radiation source: fine–focus sealed tube	1074 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.041
ω scans	θmax = 27.0°, θmin = 4.6°
Absorption correction: analytical (Alcock, 1970)	h = −16→16
Tmin = 0.616, Tmax = 0.791	k = −16→15
4610 measured reflections	l = −9→9

Refinement

Refinement on F^2	H-atom parameters constrained
Least-squares matrix: full	w = 1/[σ^2(Fo^2) + (0.0713P)^2] where P = (Fo^2 + 2Fc^2)/3
R[F^2 > 2σ(F^2)] = 0.044	(Δ/σ)max = 0.003
wR(F^2) = 0.118	Δρmax = 0.23 e Å^−3
S = 1.09	Δρmin = −0.21 e Å^−3
1212 reflections	Absolute structure: Flack (1983), with 551 Friedel pairs
73 parameters	Absolute structure parameter: −0.01 (3)
1 restraint

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.

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

	x	y	z	Uiso*/Ueq
Cu1	0	0	0	0.0670 (3)
P1	0.5	0	0.25	0.0556 (4)
C5	0.0527 (3)	0.2144 (3)	0.1582 (6)	0.0663 (9)
H5	0.007	0.2382	0.0643	0.08*
N1	0.0734 (2)	0.1106 (2)	0.1698 (4)	0.0594 (7)
C4	0.0961 (3)	0.2872 (3)	0.2790 (7)	0.0770 (12)
H4	0.0789	0.3587	0.2691	0.092*
C3	0.1657 (4)	0.2524 (4)	0.4157 (7)	0.0828 (12)
H3	0.1956	0.2998	0.501	0.099*
C2	0.1896 (5)	0.1477 (4)	0.4225 (7)	0.0879 (13)
H2	0.2386	0.1225	0.5096	0.105*
C1	0.1414 (3)	0.0798 (3)	0.3012 (6)	0.0702 (10)
H1	0.1569	0.0079	0.3109	0.084*
F2	0.5	0	0.4688 (6)	0.156 (2)
F1	0.3816 (3)	−0.0255 (6)	0.2479 (10)	0.196 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0591 (4)	0.0591 (4)	0.0828 (6)	0	0	0
P1	0.0555 (6)	0.0555 (6)	0.0558 (9)	0	0	0
C5	0.061 (2)	0.0560 (19)	0.082 (2)	0.0073 (17)	−0.0066 (18)	−0.0021 (18)
N1	0.0593 (16)	0.0497 (14)	0.0694 (16)	−0.0001 (12)	0.0014 (13)	0.0025 (12)
C4	0.078 (3)	0.058 (2)	0.095 (3)	−0.0017 (19)	0.010 (2)	−0.012 (2)
C3	0.085 (3)	0.083 (3)	0.080 (2)	−0.016 (2)	−0.001 (2)	−0.024 (2)
C2	0.101 (3)	0.091 (3)	0.072 (2)	−0.010 (3)	−0.020 (2)	−0.001 (2)
C1	0.078 (2)	0.059 (2)	0.074 (2)	−0.0019 (19)	−0.0111 (18)	0.0089 (17)
F2	0.178 (6)	0.227 (7)	0.062 (3)	−0.019 (5)	0	0
F1	0.0681 (19)	0.323 (8)	0.198 (5)	−0.030 (3)	−0.012 (3)	−0.014 (5)

Geometric parameters (Å, º)

Cu1—N1	2.061 (3)	C5—C4	1.369 (6)
Cu1—N1^i	2.061 (3)	C5—H5	0.93
Cu1—N1^ii	2.061 (3)	N1—C1	1.324 (5)
Cu1—N1^iii	2.061 (3)	C4—C3	1.379 (7)
P1—F1^iv	1.526 (4)	C4—H4	0.93
P1—F1	1.526 (4)	C3—C2	1.354 (7)
P1—F1^v	1.526 (4)	C3—H3	0.93
P1—F1^vi	1.526 (4)	C2—C1	1.357 (7)
P1—F2^iv	1.553 (5)	C2—H2	0.93
P1—F2	1.553 (5)	C1—H1	0.93
C5—N1	1.337 (5)
N1—Cu1—N1^i	110.00 (9)	F2^iv—P1—F2	180
N1—Cu1—N1^ii	110.00 (9)	N1—C5—C4	122.6 (4)
N1^i—Cu1—N1^ii	108.42 (17)	N1—C5—H5	118.7
N1—Cu1—N1^iii	108.42 (17)	C4—C5—H5	118.7
N1^i—Cu1—N1^iii	110.00 (9)	C1—N1—C5	117.1 (3)
N1^ii—Cu1—N1^iii	110.00 (9)	C1—N1—Cu1	120.3 (2)
F1^iv—P1—F1	90.006 (6)	C5—N1—Cu1	122.6 (3)
F1^iv—P1—F1^v	90.006 (6)	C5—C4—C3	118.8 (4)
F1—P1—F1^v	178.9 (6)	C5—C4—H4	120.6
F1^iv—P1—F1^vi	178.9 (6)	C3—C4—H4	120.6
F1—P1—F1^vi	90.006 (6)	C2—C3—C4	118.4 (4)
F1^v—P1—F1^vi	90.006 (6)	C2—C3—H3	120.8
F1^iv—P1—F2^iv	90.6 (3)	C4—C3—H3	120.8
F1—P1—F2^iv	89.4 (3)	C3—C2—C1	119.5 (5)
F1^v—P1—F2^iv	89.4 (3)	C3—C2—H2	120.3
F1^vi—P1—F2^iv	90.6 (3)	C1—C2—H2	120.3
F1^iv—P1—F2	89.4 (3)	N1—C1—C2	123.5 (4)
F1—P1—F2	90.6 (3)	N1—C1—H1	118.2
F1^v—P1—F2	90.6 (3)	C2—C1—H1	118.2
F1^vi—P1—F2	89.4 (3)

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