1,2-Bis(di-2-pyridylphosphino­yl)ethane

Berners-Price, S.J.; Navarro, M.; Skelton, B.W.

doi:10.1107/S1600536809004590

organic compounds

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ISSN: 2056-9890

Volume 65| Part 3| March 2009| Page o542

doi:10.1107/S1600536809004590

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1,2-Bis(di-2-pyridylphosphinoyl)ethane

Susan J. Berners-Price,^a Maribel Navarro ^a ‡ and Brian W. Skelton ^a ^*

^aChemistry, School of Biomedical, Biomolecular and Chemical Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, Perth 6009, Western Australia, Australia
^*Correspondence e-mail: brian.skelton@uwa.edu.au

(Received 20 January 2009; accepted 9 February 2009; online 18 February 2009)

The crystal structure of the title compound, C₂₂H₂₀N₄O₂P₂, consists of two independent half-molecules, both of which lie on crystallographic inversion centres. There are no significant differences between the two molecules.

Related literature

For the antitumour properties of metal complexes of bidentate tertiary phosphine ligands with pyridyl substituents, see: McKeage et al. (2000 ); Barnard & Berners-Price (2007 ); Liu et al. (2008 ). The crystal structure of the parent 1,2-bis(di-2-pyridylphosphino)ethane molecule has been determined (Jones et al., 1999 ). The structure of 1,2-bis(di-phenylphosphino)ethane dioxide (Calcagno et al., 2000 ) is similar, with the two halves of the molecule related by a pseudo-inversion centre, but this is not isomorphous with the title compound.

Experimental

Crystal data

C₂₂H₂₀N₄O₂P₂
M_r = 434.36
Triclinic, $[P \overline 1]$
a = 8.3760 (6) Å
b = 8.8496 (8) Å
c = 16.2332 (11) Å
α = 105.627 (7)°
β = 92.429 (5)°
γ = 112.559 (7)°
V = 1055.67 (16) Å³
Z = 2
Mo Kα radiation
μ = 0.23 mm⁻¹
T = 110 K
0.22 × 0.10 × 0.06 mm

Data collection

Oxford Diffraction Gemini diffractometer
Absorption correction: Gaussian (CrysAlis RED; Oxford Diffraction, 2008 $[Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ) T_min = 0.968, T_max = 0.988
10983 measured reflections
4842 independent reflections
2698 reflections with I > 2σ(I)
R_int = 0.059

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.112
S = 0.86
4842 reflections
271 parameters
H-atom parameters constrained
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Data collection: CrysAlis CCD (Oxford Diffraction, 2008 $[Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2008 $[Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEPII (Johnson, 1976 ); software used to prepare material for publication: publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809004590/fj2193sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809004590/fj2193Isup2.hkl

checkCIF report

Comment top

Bidentate tertiary phosphine ligands with pyridyl substituents, such as 1,2-bis(di-2-pyridylphosphino)ethane (d2pype) are of interest because a number of studies have shown that metal complexes with these ligands exhibit selective anti-tumour properties (McKeage et al., 2000; Barnard and Berners-Price 2007; Liu et al., 2008). During the course of our work in this area, we obtained crystals of the phosphine oxide d2pypeO₂ (I), which were suitable for X-ray diffraction studies.

Related literature top

For background on the antitumour properties of metal complexes of bidentate tertiary phosphine ligands with pyridyl substituents, see: McKeage et al. (2000); Barnard & Berners-Price (2007); Liu et al. (2008). The crystal structure of the parent 1,2-bis(di-2-pyridylphosphino)ethane molecule has been determined (Jones et al., 1999). The structure of 1,2-bis(di-phenylphosphino)ethane dioxide (Calcagno et al., 2000) is similar, with the two halfs of the molecule related by a pseudo-inversion centre, but this is not isomorphous with the title compound.

Experimental top

1,2-bis(di-2-pyridylphosphino)ethane (d2pype) was obtained from Strem Chemicals Inc. Single crystals of the title compound d2pypeO₂ (I) suitable for X-ray crystallographic analysis were obtained as a by-product of slow evaporation of a solution of d2pype and copper (I) iodide (molar ratio 2:1) in acetonitrile-tetrahydrofuran mixture.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell refinement: CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top

Fig. 1. ORTEP drawing and atom labelling for molecule n = 1. Displacement ellipsoids of non-H atoms are drawn at the 50% probablility level. The structure of the second, n = 2, molecule is very similar.

1,2-Bis(di-2-pyridylphosphinoyl)ethane top

Crystal data top

C₂₂H₂₀N₄O₂P₂	Z = 2
M_r = 434.36	F(000) = 452
Triclinic, P1	D_x = 1.366 Mg m⁻³
Hall symbol: -p 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.3760 (6) Å	Cell parameters from 2539 reflections
b = 8.8496 (8) Å	θ = 3.3–32.6°
c = 16.2332 (11) Å	µ = 0.23 mm⁻¹
α = 105.627 (7)°	T = 110 K
β = 92.429 (5)°	Plate, colourless
γ = 112.559 (7)°	0.22 × 0.10 × 0.06 mm
V = 1055.67 (16) Å³

Data collection top

Oxford Diffraction Gemini diffractometer	4842 independent reflections
Radiation source: sealed tube	2698 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.059
ω scans	θ_max = 27.5°, θ_min = 3.3°
Absorption correction: gaussian (CrysAlis RED; Oxford Diffraction, 2008)	h = −10→10
T_min = 0.968, T_max = 0.988	k = −11→11
10983 measured reflections	l = −21→21

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.112	H-atom parameters constrained
S = 0.86	w = 1/[σ²(F_o²) + (0.0495P)²] where P = (F_o² + 2F_c²)/3
4842 reflections	(Δ/σ)_max = 0.002
271 parameters	Δρ_max = 0.43 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

C₂₂H₂₀N₄O₂P₂	γ = 112.559 (7)°
M_r = 434.36	V = 1055.67 (16) Å³
Triclinic, P1	Z = 2
a = 8.3760 (6) Å	Mo Kα radiation
b = 8.8496 (8) Å	µ = 0.23 mm⁻¹
c = 16.2332 (11) Å	T = 110 K
α = 105.627 (7)°	0.22 × 0.10 × 0.06 mm
β = 92.429 (5)°

Data collection top

Oxford Diffraction Gemini diffractometer	4842 independent reflections
Absorption correction: gaussian (CrysAlis RED; Oxford Diffraction, 2008)	2698 reflections with I > 2σ(I)
T_min = 0.968, T_max = 0.988	R_int = 0.059
10983 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.112	H-atom parameters constrained
S = 0.86	Δρ_max = 0.43 e Å⁻³
4842 reflections	Δρ_min = −0.34 e Å⁻³
271 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
P1	0.18196 (9)	0.21056 (9)	0.45935 (4)	0.02233 (18)
O1	0.3253 (2)	0.3074 (2)	0.53572 (11)	0.0272 (4)
C111	0.2511 (3)	0.0876 (3)	0.37091 (16)	0.0217 (6)
N112	0.1239 (3)	−0.0366 (3)	0.30732 (14)	0.0267 (5)
C113	0.1759 (4)	−0.1218 (4)	0.24034 (17)	0.0320 (7)
H113	0.0879	−0.2109	0.195	0.038*
C114	0.3487 (4)	−0.0891 (4)	0.23254 (18)	0.0320 (7)
H114	0.3782	−0.1528	0.1831	0.038*
C115	0.4767 (4)	0.0385 (4)	0.29857 (19)	0.0372 (8)
H115	0.5969	0.0641	0.2957	0.045*
C116	0.4284 (3)	0.1287 (4)	0.36902 (18)	0.0313 (7)
H116	0.5146	0.2172	0.4153	0.038*
C121	0.1197 (3)	0.3509 (3)	0.41523 (15)	0.0227 (6)
N122	−0.0518 (3)	0.2959 (3)	0.38395 (15)	0.0300 (6)
C123	−0.0959 (4)	0.4009 (4)	0.35135 (19)	0.0352 (7)
H123	−0.216	0.3661	0.3298	0.042*
C124	0.0236 (4)	0.5571 (4)	0.34727 (17)	0.0310 (7)
H124	−0.0142	0.6263	0.3228	0.037*
C125	0.1972 (4)	0.6111 (4)	0.37892 (17)	0.0316 (7)
H125	0.2816	0.7184	0.3773	0.038*
C126	0.2464 (3)	0.5055 (3)	0.41316 (16)	0.0256 (6)
H126	0.3659	0.5388	0.4351	0.031*
C10	−0.0180 (3)	0.0583 (3)	0.47773 (16)	0.0242 (6)
H10A	−0.0786	0.121	0.5142	0.029*
H10B	−0.0962	−0.0124	0.4216	0.029*
P2	0.68020 (8)	0.27338 (9)	0.04404 (4)	0.02132 (18)
O2	0.7095 (2)	0.3187 (2)	−0.03767 (11)	0.0278 (4)
C211	0.6499 (3)	0.4398 (3)	0.12649 (16)	0.0213 (6)
N212	0.6135 (3)	0.4071 (3)	0.20118 (14)	0.0279 (5)
C213	0.6005 (4)	0.5335 (4)	0.26420 (18)	0.0327 (7)
H213	0.5758	0.5138	0.3179	0.039*
C214	0.6210 (3)	0.6903 (4)	0.2556 (2)	0.0358 (7)
H214	0.6111	0.7759	0.3025	0.043*
C215	0.6559 (3)	0.7211 (4)	0.1781 (2)	0.0347 (7)
H215	0.6695	0.8277	0.1702	0.042*
C216	0.6707 (3)	0.5931 (4)	0.11223 (19)	0.0299 (7)
H216	0.6949	0.61	0.058	0.036*
C221	0.8672 (3)	0.2545 (3)	0.09411 (16)	0.0218 (6)
N222	0.8365 (3)	0.1354 (3)	0.13511 (14)	0.0285 (5)
C223	0.9776 (4)	0.1286 (4)	0.17259 (18)	0.0335 (7)
H223	0.9594	0.0457	0.2022	0.04*
C224	1.1484 (4)	0.2342 (4)	0.17114 (18)	0.0330 (7)
H224	1.2439	0.2227	0.1984	0.04*
C225	1.1771 (3)	0.3559 (4)	0.12949 (18)	0.0342 (7)
H225	1.2929	0.4316	0.1281	0.041*
C226	1.0340 (3)	0.3661 (4)	0.08959 (17)	0.0278 (6)
H226	1.0498	0.4481	0.0596	0.033*
C20	0.4938 (3)	0.0766 (3)	0.03363 (16)	0.0212 (6)
H20A	0.4874	0.0554	0.0905	0.025*
H20B	0.3853	0.0876	0.0159	0.025*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
P1	0.0206 (4)	0.0253 (4)	0.0224 (4)	0.0096 (3)	0.0051 (3)	0.0090 (3)
O1	0.0232 (9)	0.0318 (11)	0.0235 (10)	0.0099 (9)	0.0022 (8)	0.0063 (8)
C111	0.0238 (14)	0.0239 (15)	0.0205 (13)	0.0105 (12)	0.0034 (11)	0.0107 (12)
N112	0.0328 (13)	0.0261 (14)	0.0234 (12)	0.0148 (11)	0.0026 (10)	0.0073 (11)
C113	0.0433 (18)	0.0298 (17)	0.0235 (15)	0.0168 (15)	0.0002 (13)	0.0072 (13)
C114	0.0463 (18)	0.0262 (17)	0.0295 (16)	0.0186 (15)	0.0148 (14)	0.0115 (14)
C115	0.0328 (16)	0.0311 (18)	0.050 (2)	0.0137 (14)	0.0224 (15)	0.0120 (16)
C116	0.0261 (15)	0.0256 (17)	0.0358 (17)	0.0058 (13)	0.0070 (13)	0.0063 (14)
C121	0.0250 (14)	0.0237 (15)	0.0201 (14)	0.0105 (12)	0.0067 (11)	0.0066 (12)
N122	0.0216 (12)	0.0288 (14)	0.0420 (14)	0.0083 (11)	0.0007 (10)	0.0181 (12)
C123	0.0262 (15)	0.0337 (19)	0.0480 (19)	0.0103 (14)	0.0022 (13)	0.0197 (15)
C124	0.0354 (16)	0.0282 (17)	0.0341 (16)	0.0159 (14)	0.0042 (13)	0.0128 (14)
C125	0.0342 (16)	0.0201 (16)	0.0361 (17)	0.0037 (13)	0.0084 (13)	0.0126 (13)
C126	0.0239 (14)	0.0268 (16)	0.0232 (14)	0.0083 (12)	0.0031 (11)	0.0065 (12)
C10	0.0213 (14)	0.0279 (16)	0.0256 (14)	0.0110 (12)	0.0061 (11)	0.0104 (12)
P2	0.0193 (3)	0.0198 (4)	0.0227 (4)	0.0056 (3)	0.0010 (3)	0.0071 (3)
O2	0.0289 (10)	0.0251 (11)	0.0265 (10)	0.0079 (9)	0.0018 (8)	0.0084 (9)
C211	0.0125 (12)	0.0214 (15)	0.0253 (14)	0.0052 (11)	−0.0033 (11)	0.0037 (12)
N212	0.0272 (12)	0.0358 (15)	0.0220 (12)	0.0161 (11)	−0.0015 (10)	0.0070 (11)
C213	0.0332 (16)	0.044 (2)	0.0234 (15)	0.0229 (15)	0.0014 (12)	0.0042 (14)
C214	0.0262 (15)	0.0336 (19)	0.0426 (19)	0.0162 (14)	0.0004 (14)	−0.0008 (15)
C215	0.0232 (15)	0.0180 (16)	0.057 (2)	0.0052 (12)	0.0057 (14)	0.0069 (15)
C216	0.0195 (14)	0.0267 (17)	0.0400 (17)	0.0058 (12)	0.0060 (12)	0.0104 (14)
C221	0.0225 (14)	0.0214 (15)	0.0208 (14)	0.0089 (12)	0.0039 (11)	0.0053 (12)
N222	0.0250 (12)	0.0265 (14)	0.0348 (13)	0.0087 (11)	0.0012 (10)	0.0141 (11)
C223	0.0295 (16)	0.0307 (18)	0.0421 (18)	0.0093 (14)	0.0003 (13)	0.0191 (15)
C224	0.0234 (15)	0.0388 (19)	0.0399 (18)	0.0134 (14)	−0.0027 (13)	0.0169 (15)
C225	0.0196 (14)	0.0389 (19)	0.0412 (18)	0.0069 (13)	0.0058 (13)	0.0155 (15)
C226	0.0240 (14)	0.0279 (17)	0.0321 (16)	0.0069 (13)	0.0059 (12)	0.0157 (13)
C20	0.0185 (13)	0.0212 (15)	0.0226 (14)	0.0072 (11)	−0.0002 (11)	0.0067 (11)

Geometric parameters (Å, º) top

P1—O1	1.4917 (18)	P2—O2	1.4897 (18)
P1—C10	1.799 (3)	P2—C20	1.798 (2)
P1—C121	1.809 (3)	P2—C211	1.811 (3)
P1—C111	1.815 (3)	P2—C221	1.819 (3)
C111—N112	1.344 (3)	C211—N212	1.341 (3)
C111—C116	1.391 (3)	C211—C216	1.384 (4)
N112—C113	1.339 (3)	N212—C213	1.340 (3)
C113—C114	1.381 (4)	C213—C214	1.378 (4)
C113—H113	0.95	C213—H213	0.95
C114—C115	1.377 (4)	C214—C215	1.378 (4)
C114—H114	0.95	C214—H214	0.95
C115—C116	1.380 (4)	C215—C216	1.382 (4)
C115—H115	0.95	C215—H215	0.95
C116—H116	0.95	C216—H216	0.95
C121—N122	1.352 (3)	C221—N222	1.343 (3)
C121—C126	1.383 (4)	C221—C226	1.386 (3)
N122—C123	1.339 (3)	N222—C223	1.336 (3)
C123—C124	1.382 (4)	C223—C224	1.382 (4)
C123—H123	0.95	C223—H223	0.95
C124—C125	1.371 (4)	C224—C225	1.372 (4)
C124—H124	0.95	C224—H224	0.95
C125—C126	1.381 (4)	C225—C226	1.383 (4)
C125—H125	0.95	C225—H225	0.95
C126—H126	0.95	C226—H226	0.95
C10—C10ⁱ	1.516 (5)	C20—C20ⁱⁱ	1.536 (5)
C10—H10A	0.99	C20—H20A	0.99
C10—H10B	0.99	C20—H20B	0.99

O1—P1—C10	115.87 (11)	O2—P2—C20	115.28 (11)
O1—P1—C121	112.56 (12)	O2—P2—C211	111.60 (12)
C10—P1—C121	105.88 (12)	C20—P2—C211	106.06 (11)
O1—P1—C111	110.98 (11)	O2—P2—C221	112.89 (11)
C10—P1—C111	105.53 (12)	C20—P2—C221	106.09 (12)
C121—P1—C111	105.23 (11)	C211—P2—C221	104.05 (11)
N112—C111—C116	123.1 (2)	N212—C211—C216	123.4 (2)
N112—C111—P1	116.64 (18)	N212—C211—P2	116.2 (2)
C116—C111—P1	120.2 (2)	C216—C211—P2	120.4 (2)
C113—N112—C111	116.4 (2)	C213—N212—C211	116.5 (2)
N112—C113—C114	124.6 (3)	N212—C213—C214	123.8 (3)
N112—C113—H113	117.7	N212—C213—H213	118.1
C114—C113—H113	117.7	C214—C213—H213	118.1
C115—C114—C113	118.0 (3)	C215—C214—C213	119.1 (3)
C115—C114—H114	121	C215—C214—H214	120.5
C113—C114—H114	121	C213—C214—H214	120.5
C114—C115—C116	119.3 (3)	C214—C215—C216	118.2 (3)
C114—C115—H115	120.4	C214—C215—H215	120.9
C116—C115—H115	120.4	C216—C215—H215	120.9
C115—C116—C111	118.7 (3)	C215—C216—C211	119.0 (3)
C115—C116—H116	120.6	C215—C216—H216	120.5
C111—C116—H116	120.6	C211—C216—H216	120.5
N122—C121—C126	123.0 (2)	N222—C221—C226	123.4 (2)
N122—C121—P1	117.2 (2)	N222—C221—P2	118.23 (18)
C126—C121—P1	119.86 (19)	C226—C221—P2	118.36 (19)
C123—N122—C121	116.5 (2)	C223—N222—C221	116.2 (2)
N122—C123—C124	123.6 (3)	N222—C223—C224	124.3 (3)
N122—C123—H123	118.2	N222—C223—H223	117.8
C124—C123—H123	118.2	C224—C223—H223	117.8
C125—C124—C123	119.3 (3)	C225—C224—C223	118.6 (2)
C125—C124—H124	120.4	C225—C224—H224	120.7
C123—C124—H124	120.4	C223—C224—H224	120.7
C124—C125—C126	118.4 (3)	C224—C225—C226	118.7 (3)
C124—C125—H125	120.8	C224—C225—H225	120.6
C126—C125—H125	120.8	C226—C225—H225	120.6
C125—C126—C121	119.3 (2)	C225—C226—C221	118.8 (2)
C125—C126—H126	120.4	C225—C226—H226	120.6
C121—C126—H126	120.4	C221—C226—H226	120.6
C10ⁱ—C10—P1	111.2 (2)	C20ⁱⁱ—C20—P2	111.1 (2)
C10ⁱ—C10—H10A	109.4	C20ⁱⁱ—C20—H20A	109.4
P1—C10—H10A	109.4	P2—C20—H20A	109.4
C10ⁱ—C10—H10B	109.4	C20ⁱⁱ—C20—H20B	109.4
P1—C10—H10B	109.4	P2—C20—H20B	109.4
H10A—C10—H10B	108	H20A—C20—H20B	108

Symmetry codes: (i) −x, −y, −z+1; (ii) −x+1, −y, −z.

Experimental details

Crystal data
Chemical formula	C₂₂H₂₀N₄O₂P₂
M_r	434.36
Crystal system, space group	Triclinic, P1
Temperature (K)	110
a, b, c (Å)	8.3760 (6), 8.8496 (8), 16.2332 (11)
α, β, γ (°)	105.627 (7), 92.429 (5), 112.559 (7)
V (Å³)	1055.67 (16)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.23
Crystal size (mm)	0.22 × 0.10 × 0.06

Data collection
Diffractometer	Oxford Diffraction Gemini diffractometer
Absorption correction	Gaussian (CrysAlis RED; Oxford Diffraction, 2008)
T_min, T_max	0.968, 0.988
No. of measured, independent and observed [I > 2σ(I)] reflections	10983, 4842, 2698
R_int	0.059
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.112, 0.86
No. of reflections	4842
No. of parameters	271
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.43, −0.34

Computer programs: CrysAlis CCD (Oxford Diffraction, 2008), CrysAlis RED (Oxford Diffraction, 2008), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), ORTEPII (Johnson, 1976), publCIF (Westrip, 2009).

Footnotes

‡Present Address: Laboratório de Química Bioinorgánica, Centro de Química, Instituto Venezolano de Investigaciones Científicas (IVIC), Caracas 1020-A, Venezuela.

Acknowledgements

The authors thank the Australian Research Council for financial assistance.

References

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