(4-Fluoro­phen­yl-κC)(N,N,N′,N′-tetra­methyl­ethylenedi­amine-κ2N,N′)(tri­fluoro­meth­yl-κC)palladium(II)

Du, Y.Z.; Zheng, C.G.

doi:10.1107/S1600536814007855

metal-organic compounds

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ISSN: 2056-9890

Volume 70| Part 5| May 2014| Page m179

doi:10.1107/S1600536814007855

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(4-Fluorophenyl-κC)(N,N,N′,N′-tetramethylethylenediamine-κ²N,N′)(trifluoromethyl-κC)palladium(II)

Youzhi Du ^a and ChangGe Zheng ^a ^*

^aSchool of Chemical and Material Engineering, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu Province 214122, People's Republic of China
^*Correspondence e-mail: cgzheng@jiangnan.edu.cn

(Received 27 March 2014; accepted 9 April 2014; online 16 April 2014)

In the title compound, [Pd(CF₃)(C₆H₄F)(C₆H₁₆N₂)], the Pd^II cation is four-coordinated by the two N atoms of the N,N,N′,N′-tetramethylethylenediamine ligand and by one C atom each from a 4-fluorophenyl and a trifluoromethyl ligand, in a distorted rectangular-planar geometry, with an average deviation from the least-squares plane of 0.066 (2) Å. The central coordination angles with the Pd^II atom range from 83.14 (10) to 97.25 (12)°.

CCDC reference: 996158

Related literature

For metal-mediated C—F bond-breaking and C—C bond-formation reactions in similar compounds, see: Maleckis & Sanford (2011 ); Ball et al. (2010 , 2011 ); Ye et al. (2010 ); Racowski et al. (2011 ). For similar Pd^II—CF₃ bonds, see: Grushin & Marshall (2006 ).

Experimental

Crystal data

[Pd(CF₃)(C₆H₄F)(C₆H₈N₂)]
M_r = 386.71
Monoclinic, P 2₁ /c
a = 16.6651 (19) Å
b = 8.3464 (9) Å
c = 11.4710 (13) Å
β = 103.063 (2)°
V = 1554.3 (3) Å³
Z = 4
Mo Kα radiation
μ = 1.23 mm⁻¹
T = 296 K
0.29 × 0.27 × 0.19 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.717, T_max = 0.800
8555 measured reflections
2875 independent reflections
2628 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.026
wR(F²) = 0.067
S = 1.04
2875 reflections
180 parameters
H-atom parameters constrained
Δρ_max = 0.56 e Å⁻³
Δρ_min = −0.42 e Å⁻³

Table 1
Selected bond lengths (Å)

Pd1—C12	2.004 (3)
Pd1—C13	2.017 (3)
Pd1—N1	2.172 (2)
Pd1—N2	2.206 (2)

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

CCDC reference: 996158

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S1600536814007855/vn2082sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814007855/vn2082Isup2.hkl

checkCIF report

Comment top

Trifluoromethyl palladium aryl complexes have attracted much attention due to the demand for metal-mediated C—F bond breaking and C—C bond formation reactions involving highly fluorinated substrates (Maleckis & Sanford, 2011; Ball et al., 2010; Ye et al., 2010; Racowski et al., 2011; Ball et al.,2011).

Single-crystal X-ray diffraction of the title compound reveals that Pd^II [(tmeda)Pd(p-FPh)(CF₃)] is four-coordinate. As shown in Fig. 1, the asymmetric unit comprises one Pd^II cation, a tmeda ligand (N1 and N2), a p-FPh group (C12) and a CF₃ group (C13). For primary bond lengths, see Table 1. The Pd^II—CF₃ bond length [2.015 (4) Å] (Table 1) is comparable with those in similar Pd^II complexes (Grushin & Marshall, 2006). The bidentate Xantphos ligand used in the latte study is s a larger spatial stucture ligand, and therefore [(Xantphos)Pd(Ph)(CF₃)] has an obviously greater Pd^II—CF₃ bond length with [2.069 (3) Å] (Grushin & Marshall, 2006). Fig. 2 gives the molecular packing of the title compound, viewed along the a axis.

Related literature top

For metal-mediated C—F bond-breaking and C—C bond-formation reactions in similar compounds, see: Maleckis & Sanford (2011); Ball et al. (2010, 2011); Ye et al. (2010); Racowski et al. (2011). For similar Pd^II—CF₃ bonds, see: Grushin & Marshall (2006).

Experimental top

Under nitrogen, [(tmeda)Pd(p-FPh)(I)] (445 mg, 1 mmol, 1 equiv) and CsF (3 equiv) were suspended in THF (0.145 M) in a 25 ml Schlenk flask. This mixture was stirred strongly for 10 min and then TMSCF₃ (2 equiv) was added. The reaction was stirred vigorously for 1.5 h at 30 °C. A colorless solid [(tmeda)Pd(p-FPh)(CF₃)] was obtained. 50 mg of [(tmeda)Pd(p-FPh)(CF₃)] was put into a 10 ml transparent bottle, and CH₂Cl₂ (2 ml) was added to dissolve it. The bottleneck was sealed by a plastic wrap, and lay aside the transparent bottle into a wide-mouth bottle containing diethyl ether (15 ml). Colorless block single crystals of [(tmeda)Pd(p-FPh)(CF₃)] were obtained after 3 days.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. A view of the molecular structure of [(tmeda)Pd(p-FPh)(CF₃)] with displacement ellipsoids drawn at the 30% probability level.
	Fig. 2. The molecular packing of [(tmeda)Pd(p-FPh)(CF₃)], viewed along the a axis. Atom codes: Pd checkered green spheres, F hatched green spheres, N blue dotted spheres, C black spheres, H green circled spheres.

(4-Fluorophenyl-κC)(N,N,N',N'-tetramethylethylenediamine-κ²N,N')(trifluoromethyl-κC)palladium(II) top

Crystal data top

[Pd(CF₃)(C₆H₄F)(C₆H₁₆N₂)]	F(000) = 776
M_r = 386.71	D_x = 1.653 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 6327 reflections
a = 16.6651 (19) Å	θ = 2.5–28.3°
b = 8.3464 (9) Å	µ = 1.23 mm⁻¹
c = 11.4710 (13) Å	T = 296 K
β = 103.063 (2)°	Block, colourless
V = 1554.3 (3) Å³	0.29 × 0.27 × 0.19 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	2875 independent reflections
Radiation source: fine-focus sealed tube	2628 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.032
ϕ and ω scans	θ_max = 25.5°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −20→19
T_min = 0.717, T_max = 0.800	k = −7→10
8555 measured reflections	l = −13→13

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.026	H-atom parameters constrained
wR(F²) = 0.067	w = 1/[σ²(F_o²) + (0.0257P)² + 1.3072P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
2875 reflections	Δρ_max = 0.56 e Å⁻³
180 parameters	Δρ_min = −0.42 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0130 (7)

Crystal data top

[Pd(CF₃)(C₆H₄F)(C₆H₁₆N₂)]	V = 1554.3 (3) Å³
M_r = 386.71	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 16.6651 (19) Å	µ = 1.23 mm⁻¹
b = 8.3464 (9) Å	T = 296 K
c = 11.4710 (13) Å	0.29 × 0.27 × 0.19 mm
β = 103.063 (2)°

Data collection top

Bruker APEXII CCD diffractometer	2875 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	2628 reflections with I > 2σ(I)
T_min = 0.717, T_max = 0.800	R_int = 0.032
8555 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.026	0 restraints
wR(F²) = 0.067	H-atom parameters constrained
S = 1.04	Δρ_max = 0.56 e Å⁻³
2875 reflections	Δρ_min = −0.42 e Å⁻³
180 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.1947 (3)	0.3541 (4)	−0.1824 (3)	0.0676 (10)
H1A	0.1625	0.2614	−0.2124	0.101*
H1B	0.2458	0.3510	−0.2077	0.101*
H1C	0.1649	0.4492	−0.2130	0.101*
C2	0.1308 (2)	0.3660 (4)	−0.0178 (4)	0.0697 (10)
H2A	0.1389	0.3639	0.0677	0.104*
H2B	0.0969	0.2770	−0.0517	0.104*
H2C	0.1041	0.4643	−0.0482	0.104*
C3	0.2600 (3)	0.4968 (4)	−0.0004 (4)	0.0770 (12)
H3A	0.2441	0.5870	−0.0539	0.092*
H3B	0.2472	0.5237	0.0757	0.092*
C4	0.3477 (2)	0.4711 (5)	0.0176 (5)	0.0831 (13)
H4A	0.3763	0.5657	0.0548	0.100*
H4B	0.3611	0.4580	−0.0599	0.100*
C5	0.3906 (3)	0.3625 (5)	0.2209 (4)	0.0832 (14)
H5A	0.4169	0.2726	0.2661	0.125*
H5B	0.3382	0.3815	0.2399	0.125*
H5C	0.4247	0.4558	0.2406	0.125*
C6	0.4590 (2)	0.2862 (5)	0.0683 (4)	0.0691 (10)
H6A	0.4948	0.3776	0.0825	0.104*
H6B	0.4514	0.2533	−0.0137	0.104*
H6C	0.4831	0.2000	0.1199	0.104*
C7	0.12779 (18)	−0.0466 (4)	−0.0076 (3)	0.0492 (7)
H7	0.1232	−0.0043	0.0656	0.059*
C8	0.0662 (2)	−0.1472 (4)	−0.0689 (4)	0.0658 (10)
H8	0.0208	−0.1718	−0.0378	0.079*
C9	0.0738 (2)	−0.2090 (4)	−0.1757 (4)	0.0658 (10)
C10	0.1397 (3)	−0.1777 (4)	−0.2232 (3)	0.0675 (11)
H10	0.1438	−0.2216	−0.2961	0.081*
C11	0.2004 (2)	−0.0786 (4)	−0.1598 (3)	0.0557 (8)
H11	0.2465	−0.0585	−0.1904	0.067*
C12	0.19541 (17)	−0.0076 (3)	−0.0519 (2)	0.0389 (6)
C13	0.34552 (19)	−0.0443 (4)	0.1069 (3)	0.056
F1	0.30400 (16)	−0.1597 (3)	0.1466 (3)	0.0905 (8)
F2	0.40331 (16)	−0.0049 (3)	0.2069 (3)	0.1081 (10)
F3	0.3877 (2)	−0.1208 (3)	0.0386 (3)	0.1207 (12)
F4	0.01374 (16)	−0.3096 (3)	−0.2362 (3)	0.1088 (10)
N1	0.21161 (16)	0.3549 (3)	−0.0509 (2)	0.0455 (6)
N2	0.37856 (16)	0.3287 (3)	0.0931 (2)	0.0483 (6)
Pd1	0.282550 (12)	0.14760 (2)	0.027333 (17)	0.03517 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.092 (3)	0.062 (2)	0.0461 (18)	0.0159 (19)	0.0097 (18)	0.0128 (15)
C2	0.070 (2)	0.062 (2)	0.082 (3)	0.0226 (18)	0.027 (2)	0.0115 (19)
C3	0.080 (3)	0.0372 (19)	0.101 (3)	−0.0030 (18)	−0.006 (2)	0.0041 (19)
C4	0.071 (3)	0.045 (2)	0.132 (4)	−0.0135 (18)	0.019 (2)	0.009 (2)
C5	0.076 (3)	0.109 (4)	0.067 (2)	−0.034 (2)	0.022 (2)	−0.039 (2)
C6	0.0481 (19)	0.087 (3)	0.075 (2)	−0.0154 (19)	0.0203 (17)	−0.011 (2)
C7	0.0449 (16)	0.0494 (18)	0.0536 (17)	−0.0037 (14)	0.0119 (13)	−0.0032 (14)
C8	0.0386 (17)	0.060 (2)	0.097 (3)	−0.0064 (15)	0.0099 (18)	0.0007 (19)
C9	0.056 (2)	0.0447 (19)	0.079 (2)	−0.0073 (16)	−0.0217 (19)	−0.0024 (18)
C10	0.099 (3)	0.0480 (19)	0.0467 (18)	−0.0103 (19)	−0.0019 (19)	−0.0066 (15)
C11	0.074 (2)	0.0457 (18)	0.0504 (17)	−0.0156 (16)	0.0212 (16)	−0.0048 (15)
C12	0.0413 (14)	0.0342 (14)	0.0388 (13)	−0.0015 (11)	0.0038 (11)	0.0021 (11)
C13	0.044	0.049	0.072	−0.003	0.008	−0.006
F1	0.0801 (16)	0.0650 (15)	0.118 (2)	0.0029 (11)	0.0049 (14)	0.0432 (13)
F2	0.0912 (18)	0.0810 (17)	0.119 (2)	0.0006 (14)	−0.0460 (16)	0.0218 (15)
F3	0.129 (2)	0.098 (2)	0.154 (3)	0.0678 (19)	0.071 (2)	0.0274 (19)
F4	0.0831 (17)	0.0773 (16)	0.135 (2)	−0.0264 (14)	−0.0406 (16)	−0.0194 (16)
N1	0.0537 (15)	0.0382 (14)	0.0420 (13)	0.0000 (10)	0.0050 (11)	0.0040 (10)
N2	0.0434 (13)	0.0466 (14)	0.0544 (15)	−0.0089 (11)	0.0100 (11)	−0.0056 (12)
Pd1	0.03454 (14)	0.03201 (14)	0.03823 (14)	−0.00229 (8)	0.00669 (9)	−0.00038 (8)

Geometric parameters (Å, º) top

C1—N1	1.471 (4)	C6—H6B	0.9600
C1—H1A	0.9600	C6—H6C	0.9600
C1—H1B	0.9600	C7—C12	1.375 (4)
C1—H1C	0.9600	C7—C8	1.388 (5)
C2—N1	1.483 (5)	C7—H7	0.9300
C2—H2A	0.9600	C8—C9	1.361 (6)
C2—H2B	0.9600	C8—H8	0.9300
C2—H2C	0.9600	C9—C10	1.357 (6)
C3—C4	1.446 (6)	C9—F4	1.369 (4)
C3—N1	1.475 (4)	C10—C11	1.379 (5)
C3—H3A	0.9700	C10—H10	0.9300
C3—H3B	0.9700	C11—C12	1.392 (4)
C4—N2	1.492 (5)	C11—H11	0.9300
C4—H4A	0.9700	Pd1—C12	2.004 (3)
C4—H4B	0.9700	C13—F1	1.325 (4)
C5—N2	1.462 (5)	C13—F3	1.329 (4)
C5—H5A	0.9600	C13—F2	1.361 (4)
C5—H5B	0.9600	Pd1—C13	2.017 (3)
C5—H5C	0.9600	Pd1—N1	2.172 (2)
C6—N2	1.475 (4)	Pd1—N2	2.206 (2)
C6—H6A	0.9600

N1—C1—H1A	109.5	C9—C8—C7	118.5 (4)
N1—C1—H1B	109.5	C9—C8—H8	120.8
H1A—C1—H1B	109.5	C7—C8—H8	120.8
N1—C1—H1C	109.5	C10—C9—C8	122.4 (3)
H1A—C1—H1C	109.5	C10—C9—F4	118.7 (4)
H1B—C1—H1C	109.5	C8—C9—F4	118.9 (4)
N1—C2—H2A	109.5	C9—C10—C11	117.9 (3)
N1—C2—H2B	109.5	C9—C10—H10	121.1
H2A—C2—H2B	109.5	C11—C10—H10	121.1
N1—C2—H2C	109.5	C10—C11—C12	122.7 (3)
H2A—C2—H2C	109.5	C10—C11—H11	118.7
H2B—C2—H2C	109.5	C12—C11—H11	118.7
C4—C3—N1	112.4 (3)	C7—C12—C11	116.5 (3)
C4—C3—H3A	109.1	C7—C12—Pd1	123.8 (2)
N1—C3—H3A	109.1	C11—C12—Pd1	119.7 (2)
C4—C3—H3B	109.1	F1—C13—F3	103.9 (3)
N1—C3—H3B	109.1	F1—C13—F2	102.2 (3)
H3A—C3—H3B	107.8	F3—C13—F2	104.2 (3)
C3—C4—N2	113.9 (3)	F1—C13—Pd1	118.3 (2)
C3—C4—H4A	108.8	F3—C13—Pd1	113.9 (3)
N2—C4—H4A	108.8	F2—C13—Pd1	112.8 (2)
C3—C4—H4B	108.8	C1—N1—C3	111.6 (3)
N2—C4—H4B	108.8	C1—N1—C2	106.8 (3)
H4A—C4—H4B	107.7	C3—N1—C2	107.2 (3)
N2—C5—H5A	109.5	C1—N1—Pd1	112.3 (2)
N2—C5—H5B	109.5	C3—N1—Pd1	106.2 (2)
H5A—C5—H5B	109.5	C2—N1—Pd1	112.7 (2)
N2—C5—H5C	109.5	C5—N2—C6	108.4 (3)
H5A—C5—H5C	109.5	C5—N2—C4	112.3 (3)
H5B—C5—H5C	109.5	C6—N2—C4	106.8 (3)
N2—C6—H6A	109.5	C5—N2—Pd1	113.6 (2)
N2—C6—H6B	109.5	C6—N2—Pd1	112.9 (2)
H6A—C6—H6B	109.5	C4—N2—Pd1	102.7 (2)
N2—C6—H6C	109.5	C12—Pd1—C13	86.65 (12)
H6A—C6—H6C	109.5	C12—Pd1—N1	93.25 (10)
H6B—C6—H6C	109.5	C13—Pd1—N1	177.08 (12)
C12—C7—C8	122.0 (3)	C12—Pd1—N2	173.23 (10)
C12—C7—H7	119.0	C13—Pd1—N2	97.25 (12)
C8—C7—H7	119.0	N1—Pd1—N2	83.14 (10)

N1—C3—C4—N2	−55.4 (5)	C11—C12—Pd1—N1	95.3 (2)
C12—C7—C8—C9	0.3 (5)	F1—C13—Pd1—C12	−40.6 (3)
C7—C8—C9—C10	1.0 (6)	F3—C13—Pd1—C12	81.9 (3)
C7—C8—C9—F4	179.4 (3)	F2—C13—Pd1—C12	−159.6 (3)
C8—C9—C10—C11	−0.3 (6)	F1—C13—Pd1—N2	145.0 (3)
F4—C9—C10—C11	−178.7 (3)	F3—C13—Pd1—N2	−92.6 (3)
C9—C10—C11—C12	−1.6 (5)	F2—C13—Pd1—N2	25.9 (3)
C8—C7—C12—C11	−2.1 (5)	C1—N1—Pd1—C12	−61.5 (2)
C8—C7—C12—Pd1	176.0 (2)	C3—N1—Pd1—C12	176.3 (2)
C10—C11—C12—C7	2.8 (5)	C2—N1—Pd1—C12	59.1 (2)
C10—C11—C12—Pd1	−175.4 (3)	C1—N1—Pd1—N2	112.8 (2)
C4—C3—N1—C1	−87.2 (4)	C3—N1—Pd1—N2	−9.5 (2)
C4—C3—N1—C2	156.3 (4)	C2—N1—Pd1—N2	−126.6 (2)
C4—C3—N1—Pd1	35.5 (4)	C5—N2—Pd1—C13	−71.4 (3)
C3—C4—N2—C5	−80.8 (4)	C6—N2—Pd1—C13	52.6 (3)
C3—C4—N2—C6	160.5 (4)	C4—N2—Pd1—C13	167.1 (3)
C3—C4—N2—Pd1	41.5 (4)	C5—N2—Pd1—N1	105.7 (3)
C7—C12—Pd1—C13	94.4 (3)	C6—N2—Pd1—N1	−130.4 (2)
C11—C12—Pd1—C13	−87.6 (3)	C4—N2—Pd1—N1	−15.8 (2)
C7—C12—Pd1—N1	−82.7 (3)

Selected bond lengths (Å) top

Pd1—C12	2.004 (3)	Pd1—N1	2.172 (2)
Pd1—C13	2.017 (3)	Pd1—N2	2.206 (2)

Acknowledgements

This work was supported by the Research Institute of Element-Organic Chemistry of East China Institute of Technology

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