A P,O,P′-tridentate mixed-donor scorpionate ligand: 6-[4,6-bis­(diphenyl­phosphino)-10H-phenoxazin-10-yl]hexan-1-ol

Marimuthu, T.; Bala, M.D.; Friedrich, H.B.

doi:10.1107/S1600536808030134

organic compounds

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ISSN: 2056-9890

Volume 64| Part 10| October 2008| Pages o1984-o1985

doi:10.1107/S1600536808030134

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A P,O,P′-tridentate mixed-donor scorpionate ligand: 6-[4,6-bis(diphenylphosphino)-10H-phenoxazin-10-yl]hexan-1-ol

Thashree Marimuthu,^a Muhammad D. Bala ^a ^* and Holger B. Friedrich ^a

^aSchool of Chemistry, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa
^*Correspondence e-mail: bala@ukzn.ac.za

(Received 3 July 2008; accepted 18 September 2008; online 20 September 2008)

The title compound, C₄₂H₃₉NO₂P₂, is a P,O,P′-tridentate scorpionate-type ligand and has one molecule in the asymmetric unit. The angles involving the P atoms range from 100.21 (7) to 104.89 (7)°. The N-hexanol group was found to be disordered and was refined over two positions with final occupancies of 0.683 (3) and 0.317 (3) which affected the C—O and C—N bond lengths. The bond lengths for C—O range from 1.402 (2) to 1.415 (2) Å and for C—N from 1.410 (2) to 1.448 (3) Å for the major disorder component; the corresponding ranges for the minor disorder component are 1.429 (3)–1.408 (3) and 1.474 (3)–1.474 (4) Å.

Related literature

For scorpionate type ligands based on the nixantphos backbone, see: Marimuthu et al. (2008a ,b ). For scorpionate ligands, see: Pettinari, (2004 ); Trofimenko (1993 ); Leung, (2007 ); Mayer et al. (1994 ). For hydrogen bonding, see: Chen & Craven (1995 ); Monge et al. (1978 ). For details of the synthesis, see: Reymond et al. (1996 ); Van der Veen et al. (2000 ). For a related structure, see: Osiński et al. (2005 ).

Experimental

Crystal data

C₄₂H₃₉NO₂P₂
M_r = 651.68
Triclinic, $[P \overline 1]$
a = 10.4258 (2) Å
b = 11.1402 (3) Å
c = 15.3590 (4) Å
α = 75.777 (1)°
β = 88.583 (1)°
γ = 79.453 (2)°
V = 1699.60 (7) Å³
Z = 2
Mo Kα radiation
μ = 0.17 mm⁻¹
T = 173 (2) K
0.51 × 0.31 × 0.29 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: none
30269 measured reflections
8211 independent reflections
6458 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.122
S = 1.08
8211 reflections
489 parameters
115 restraints
H-atom parameters constrained
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.30 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ); cell refinement: SAINT-NT (Bruker, 2005); data reduction: SAINT-NT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: PLATON (Spek, 2003 ) and ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808030134/rt2023sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808030134/rt2023Isup2.hkl

checkCIF report

Comment top

The title compound (I) was synthesized as part of our on going investigation of scorpionate type ligands based on the nixantphos backbone (Marimuthu et al.,2008a,b). Scorpionate ligands coordinate to metal centres to give unique types of coordination compounds. These compounds exhibit a characteristic type of geometry, enforced by the pincers and the third donor which comes across the plane (formed by metal and pincers) to coordinate to the metal (Pettinari, 2004). The common feature of most scorpionate ligands is that they uniformly contain a single type of donor atom, typically N– (Trofimenko, 1993), O– (Leung, 2007), or P– (Mayer et al., 1994). In contrast, this research is focused on the preparation of chelating P-donor ligands based on a nixantphos backbone functionalized by various hard and soft donors that serve as the third binding site of the ligands. The funtionalized N-hexanol group was found to be disordered and was refined over two positions with final occupancies of 0.68 and 0.32. If the nixantphos moiety is considered as the 'head' of the compound (I) and the hexanol chain as its 'tail', then the packing in (I) can be described as stacked in a 'head' to 'tail' arrangement. Due to this arrangement several intermolecular interactions especially of type O2—H···O1 are observed between the 'heads' and 'tails' of adjacent molecules. The H···O1 interatomic lengths range from 2.733 to 3.346 Å. Although these are unusually long for classical hydrogen bonding (Chen and Craven, 1995; Monge et al., 1978), the interactions are significant in maintaining the integrity of the disordered crystal structure. The bond angles involving the P atoms range from 100.21 (7) ° to 104.89 (7) °.

Related literature top

For scorpionate type ligands based on the nixantphos backbone, see: Marimuthu et al. (2008a,b). For scorionate ligands, see: Pettinari, (2004); Trofimenko (1993); Leung, (2007); Mayer et al. (1994). For hydrogen bonding, see: Chen & Craven (1995); Monge et al. (1978). For details of the synthesis, see: Reymond et al. (1996); Van der Veen et al. (2000). For a related structure, see: Osiński et al. (2005).

Experimental top

A two part synthesis involving: a) alkylation (Reymond et al., 1996), and b) deprotection (van der Veen et al., 2000) was adapted from literature. Nixantphos (0.20 g, 0.36 mmol) was dissolved in 4 ml of dry DMF to which NaH (0.22 g, 0.54 millimol, 60% dispersed in mineral oil) was added, followed by the addition of (6-bromohexyloxy)(tertbutyl)dimethylsilane (0.18 g, 0.63 millimol). The resulting mixture was stirred overnight at 100 °C. The reaction was cooled to room temperature and hydrolysed with 10 ml of water. The organic phase was extracted with 4 x 15 ml ethyl acetate and the combined fractions dried over sodium sulfate. Thereafter the solvent was removed in vacuo and the residue chromatographed with 10% hexane/ethyl acetate to give the protected precursor of the title compound (I). The precursor was dissolved in 25 ml THF, and 2.5 equivalents of tetra-n-butylammoniumflouride trihydrate was added. The reaction was left to stir overnight at room temperature and was followed by aqueous work-up. The resulting crude product of compound (I) was chromatographed with 20% hexane/ethyl acetate and recrystalized from a solution of dichloromethane/ethanol (1:1) to yield 23% of pale yellow crystals of pure (I). m.p. 440–441 K.

Spectroscopic analysis: ¹H NMR (400 MHz, CDCl₃, δ, p.p.m): = 1.67–1.24 (m, CH₂), 3.46 (t, CH₂OH), 3.65 (t, NCH₂),5.97 (d, 2H; J(H,H) = 7.8 Hz), 6.41 (d, 2H; J(H,H) = 7.8 Hz), 6.64 (t, 2H; J(H,H) = 7.8 Hz), 7.20–7.18 (m, 20H).

¹³C NMR (400 MHz, CDCl₃, δ, p.p.m): = 24.9 (CH₂),25.8 (CH₂), 27.0 (CH₂), 32.9 (CH₂), 44.8 (CH₂), 63.0 (OCH₂), 111.7 (CH), 123.6, 125.1 (CH), 128.1 (CH), 128.1 (CH), 128.1 (CH), 128.2 (CH), 134.0 (m, CH), 137.0 (t, C), 147.1 (t, CO).

³¹P NMR (600 MHz, CDCl₃, δ, p.p.m): = -19.2.

MS m/z -[fragment]-(%): 651.2485 –[M] – (34%), calculated = 651.25 for C₄₂H₃₉NO₂P₂.

FTIR: cm^-1 = 3582(s, OH), 3043(m), 3047(m), 2919(m), 2848(m), 1943(m), 1874(m), 1803(m), 1574(s), 1545(s), 1550(w), 1459, 1414(s), 1375(s), 1269(w), 1224(m), 1176(s), 1089 (CO), 742(s), 692(s).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-NT (Bruker, 2005); data reduction: SAINT-NT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003) and ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. Molecular structure of the title complex. Thermal ellipsoids are shown at 50% probability levels.

6-[4,6-bis(diphenylphosphino)-10H-phenoxazin-10-yl]hexan-1-ol top

Crystal data top

C₄₂H₃₉NO₂P₂	Z = 2
M_r = 651.68	F(000) = 688
Triclinic, P1	D_x = 1.273 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 10.4258 (2) Å	Cell parameters from 5800 reflections
b = 11.1402 (3) Å	θ = 2.4–28.4°
c = 15.3590 (4) Å	µ = 0.17 mm⁻¹
α = 75.777 (1)°	T = 173 K
β = 88.583 (1)°	Prismic, yellow
γ = 79.453 (2)°	0.51 × 0.31 × 0.29 mm
V = 1699.60 (7) Å³

Data collection top

Bruker SMART CCD area-detector diffractometer	6458 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.043
Graphite monochromator	θ_max = 28.0°, θ_min = 1.4°
ϕ and ω scans	h = −13→13
30269 measured reflections	k = −14→14
8211 independent reflections	l = −20→19

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.122	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.0654P)² + 0.218P] where P = (F_o² + 2F_c²)/3
8211 reflections	(Δ/σ)_max = 0.001
489 parameters	Δρ_max = 0.42 e Å⁻³
115 restraints	Δρ_min = −0.30 e Å⁻³

Crystal data top

C₄₂H₃₉NO₂P₂	γ = 79.453 (2)°
M_r = 651.68	V = 1699.60 (7) Å³
Triclinic, P1	Z = 2
a = 10.4258 (2) Å	Mo Kα radiation
b = 11.1402 (3) Å	µ = 0.17 mm⁻¹
c = 15.3590 (4) Å	T = 173 K
α = 75.777 (1)°	0.51 × 0.31 × 0.29 mm
β = 88.583 (1)°

Data collection top

Bruker SMART CCD area-detector diffractometer	6458 reflections with I > 2σ(I)
30269 measured reflections	R_int = 0.043
8211 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	115 restraints
wR(F²) = 0.122	H-atom parameters constrained
S = 1.08	Δρ_max = 0.42 e Å⁻³
8211 reflections	Δρ_min = −0.30 e Å⁻³
489 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	Occ. (<1)
C1	0.10850 (18)	0.95659 (15)	0.14870 (12)	0.0403 (4)
C2	0.04581 (16)	1.07476 (14)	0.15453 (11)	0.0341 (4)
H2	0.0560	1.1469	0.1087	0.041*
C3	−0.03150 (17)	1.08802 (15)	0.22679 (12)	0.0386 (4)
H3	−0.0729	1.1698	0.2307	0.046*
C4	−0.04999 (17)	0.98523 (15)	0.29330 (12)	0.0363 (4)
H4	−0.1037	0.9965	0.3426	0.044*
C5	0.00996 (14)	0.86440 (13)	0.28850 (10)	0.0263 (3)
C6	0.08763 (16)	0.85335 (14)	0.21642 (12)	0.0348 (4)
C7	0.21739 (16)	0.71321 (15)	0.14128 (11)	0.0338 (4)
C8	0.26737 (14)	0.58992 (14)	0.14232 (10)	0.0261 (3)
C9	0.34299 (16)	0.56684 (16)	0.07008 (11)	0.0350 (4)
H9	0.3794	0.4827	0.0687	0.042*
C10	0.36543 (17)	0.66473 (17)	0.00077 (11)	0.0381 (4)
H10	0.4169	0.6474	−0.0481	0.046*
C11	0.31406 (16)	0.78831 (16)	0.00116 (11)	0.0347 (4)
H11	0.3297	0.8551	−0.0474	0.042*
C12	0.23980 (18)	0.81449 (15)	0.07248 (12)	0.0393 (4)
C13	0.2513 (3)	1.0437 (2)	0.02672 (16)	0.0311 (6)	0.683 (3)
H13A	0.3408	1.0148	0.0080	0.037*	0.683 (3)
H13B	0.2561	1.1077	0.0607	0.037*	0.683 (3)
C14	0.1672 (2)	1.1065 (2)	−0.05704 (17)	0.0350 (6)	0.683 (3)
H14A	0.0766	1.1336	−0.0394	0.042*	0.683 (3)
H14B	0.1658	1.0449	−0.0936	0.042*	0.683 (3)
C15	0.2183 (2)	1.2209 (2)	−0.11373 (16)	0.0357 (6)	0.683 (3)
H15A	0.1520	1.2685	−0.1606	0.043*	0.683 (3)
H15B	0.2304	1.2770	−0.0748	0.043*	0.683 (3)
C16	0.3457 (4)	1.1862 (4)	−0.1583 (3)	0.0408 (10)	0.683 (3)
H16A	0.4121	1.1400	−0.1111	0.049*	0.683 (3)
H16B	0.3338	1.1283	−0.1959	0.049*	0.683 (3)
C17	0.3969 (4)	1.2969 (4)	−0.2162 (3)	0.0381 (11)	0.683 (3)
H17A	0.4147	1.3514	−0.1775	0.046*	0.683 (3)
H17B	0.3276	1.3467	−0.2602	0.046*	0.683 (3)
C13B	0.1715 (5)	1.0427 (5)	−0.0122 (3)	0.0339 (12)	0.317 (3)
H13C	0.0917	1.1085	−0.0222	0.041*	0.317 (3)
H13D	0.1896	1.0151	−0.0685	0.041*	0.317 (3)
C14B	0.2856 (6)	1.0974 (6)	0.0113 (4)	0.0476 (15)	0.317 (3)
H14C	0.3653	1.0317	0.0193	0.057*	0.317 (3)
H14D	0.2686	1.1205	0.0693	0.057*	0.317 (3)
C15B	0.3105 (7)	1.2130 (5)	−0.0593 (4)	0.0532 (17)	0.317 (3)
H15C	0.2255	1.2677	−0.0802	0.064*	0.317 (3)
H15D	0.3604	1.2610	−0.0306	0.064*	0.317 (3)
C16B	0.3839 (9)	1.1846 (9)	−0.1399 (5)	0.045 (2)	0.317 (3)
H16C	0.3285	1.1491	−0.1747	0.054*	0.317 (3)
H16D	0.4633	1.1206	−0.1193	0.054*	0.317 (3)
C17B	0.4226 (10)	1.3013 (9)	−0.1998 (7)	0.045 (3)	0.317 (3)
H17C	0.3443	1.3578	−0.2316	0.054*	0.317 (3)
H17D	0.4618	1.3473	−0.1630	0.054*	0.317 (3)
C18	0.51909 (17)	1.26407 (17)	−0.26682 (12)	0.0400 (4)
H18A	0.5914	1.2174	−0.2242	0.048*
H18B	0.5038	1.2105	−0.3069	0.048*
C21	0.14465 (15)	0.69008 (15)	0.43719 (10)	0.0297 (3)
C22	0.20133 (17)	0.56556 (16)	0.47588 (11)	0.0374 (4)
H22	0.1618	0.4991	0.4667	0.045*
C23	0.31469 (19)	0.5377 (2)	0.52756 (12)	0.0483 (5)
H23	0.3525	0.4524	0.5536	0.058*
C24	0.37245 (18)	0.6324 (2)	0.54126 (13)	0.0506 (5)
H24	0.4510	0.6127	0.5761	0.061*
C25	0.31694 (18)	0.7565 (2)	0.50468 (14)	0.0477 (5)
H25	0.3559	0.8221	0.5158	0.057*
C26	0.20443 (16)	0.78555 (17)	0.45171 (12)	0.0390 (4)
H26	0.1680	0.8711	0.4252	0.047*
C31	−0.12692 (15)	0.78316 (14)	0.44558 (11)	0.0289 (3)
C32	−0.09950 (16)	0.80924 (17)	0.52627 (11)	0.0360 (4)
H32	−0.0115	0.7957	0.5467	0.043*
C33	−0.19952 (19)	0.85480 (18)	0.57712 (13)	0.0447 (4)
H33	−0.1796	0.8720	0.6323	0.054*
C34	−0.32668 (19)	0.87525 (19)	0.54871 (13)	0.0488 (5)
H34	−0.3948	0.9059	0.5842	0.059*
C35	−0.35526 (18)	0.8513 (2)	0.46878 (15)	0.0544 (5)
H35	−0.4433	0.8669	0.4481	0.065*
C36	−0.25611 (17)	0.80432 (19)	0.41813 (13)	0.0443 (4)
H36	−0.2771	0.7862	0.3634	0.053*
C41	0.35700 (14)	0.33337 (13)	0.22967 (10)	0.0259 (3)
C42	0.32873 (17)	0.22495 (15)	0.21177 (11)	0.0332 (4)
H42	0.2419	0.2223	0.1960	0.040*
C43	0.42648 (18)	0.11970 (16)	0.21672 (12)	0.0401 (4)
H43	0.4058	0.0459	0.2043	0.048*
C44	0.55208 (18)	0.12183 (16)	0.23939 (12)	0.0402 (4)
H44	0.6182	0.0496	0.2431	0.048*
C45	0.58230 (17)	0.22873 (16)	0.25679 (12)	0.0384 (4)
H45	0.6695	0.2305	0.2721	0.046*
C46	0.48592 (15)	0.33387 (15)	0.25208 (11)	0.0327 (4)
H46	0.5078	0.4073	0.2643	0.039*
C51	0.08077 (14)	0.43856 (13)	0.20881 (11)	0.0278 (3)
C52	−0.01832 (16)	0.43793 (14)	0.27117 (12)	0.0335 (4)
H52	−0.0006	0.4460	0.3296	0.040*
C53	−0.14243 (16)	0.42574 (15)	0.24918 (13)	0.0397 (4)
H53	−0.2093	0.4257	0.2924	0.048*
C54	−0.16890 (17)	0.41373 (16)	0.16488 (13)	0.0416 (4)
H54	−0.2546	0.4074	0.1493	0.050*
C55	−0.07114 (17)	0.41088 (16)	0.10282 (12)	0.0381 (4)
H55	−0.0891	0.4002	0.0451	0.046*
C56	0.05286 (16)	0.42354 (15)	0.12440 (11)	0.0334 (4)
H56	0.1196	0.4220	0.0812	0.040*
N1	0.2074 (2)	0.93759 (18)	0.08664 (16)	0.0336 (6)	0.683 (3)
N1B	0.1493 (5)	0.9347 (3)	0.0605 (2)	0.0303 (12)	0.317 (3)
O1	0.1616 (2)	0.73286 (17)	0.22274 (13)	0.0313 (5)	0.683 (3)
O1B	0.1088 (4)	0.7331 (3)	0.1957 (3)	0.0310 (11)	0.317 (3)
O2	0.55085 (14)	1.37799 (13)	−0.31765 (9)	0.0533 (4)
H2A	0.6155	1.3624	−0.3495	0.080*
P1	−0.00697 (4)	0.71914 (4)	0.37224 (3)	0.02700 (11)
P2	0.23648 (4)	0.46903 (3)	0.24223 (3)	0.02641 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0484 (10)	0.0244 (8)	0.0439 (10)	−0.0034 (7)	0.0186 (8)	−0.0049 (7)
C2	0.0402 (9)	0.0205 (7)	0.0384 (9)	−0.0043 (6)	0.0050 (7)	−0.0023 (6)
C3	0.0459 (10)	0.0220 (7)	0.0445 (10)	0.0017 (7)	0.0055 (8)	−0.0081 (7)
C4	0.0406 (9)	0.0274 (8)	0.0384 (9)	0.0002 (7)	0.0085 (7)	−0.0088 (7)
C5	0.0253 (7)	0.0235 (7)	0.0288 (8)	−0.0030 (6)	0.0007 (6)	−0.0053 (6)
C6	0.0393 (9)	0.0198 (7)	0.0409 (9)	0.0003 (6)	0.0120 (7)	−0.0045 (7)
C7	0.0366 (9)	0.0267 (8)	0.0364 (9)	−0.0040 (6)	0.0157 (7)	−0.0074 (7)
C8	0.0260 (7)	0.0249 (7)	0.0275 (8)	−0.0038 (6)	0.0012 (6)	−0.0075 (6)
C9	0.0390 (9)	0.0311 (8)	0.0328 (9)	0.0021 (7)	0.0051 (7)	−0.0106 (7)
C10	0.0397 (9)	0.0426 (9)	0.0305 (9)	−0.0024 (7)	0.0097 (7)	−0.0109 (7)
C11	0.0372 (9)	0.0347 (8)	0.0301 (8)	−0.0071 (7)	0.0086 (7)	−0.0044 (7)
C12	0.0458 (10)	0.0259 (8)	0.0433 (10)	−0.0056 (7)	0.0181 (8)	−0.0055 (7)
C13	0.0376 (14)	0.0273 (12)	0.0290 (12)	−0.0123 (10)	0.0002 (10)	−0.0036 (9)
C14	0.0378 (13)	0.0321 (13)	0.0327 (13)	−0.0079 (10)	−0.0005 (10)	−0.0024 (10)
C15	0.0464 (14)	0.0261 (11)	0.0297 (12)	−0.0035 (10)	0.0017 (10)	0.0000 (9)
C16	0.052 (2)	0.0308 (15)	0.0396 (17)	−0.0127 (14)	0.0084 (15)	−0.0063 (13)
C17	0.058 (2)	0.0271 (15)	0.0310 (17)	−0.0115 (14)	0.0083 (16)	−0.0093 (12)
C13B	0.045 (3)	0.029 (3)	0.027 (3)	−0.009 (2)	0.006 (2)	−0.004 (2)
C14B	0.055 (3)	0.049 (3)	0.049 (3)	−0.028 (3)	0.013 (3)	−0.018 (2)
C15B	0.069 (4)	0.045 (3)	0.057 (3)	−0.031 (3)	0.026 (3)	−0.023 (2)
C16B	0.057 (5)	0.037 (3)	0.050 (4)	−0.022 (3)	0.014 (3)	−0.019 (3)
C17B	0.064 (5)	0.041 (4)	0.039 (4)	−0.025 (3)	0.012 (4)	−0.017 (3)
C18	0.0402 (9)	0.0393 (9)	0.0395 (10)	−0.0092 (7)	−0.0001 (7)	−0.0059 (8)
C21	0.0262 (7)	0.0312 (8)	0.0290 (8)	−0.0011 (6)	0.0053 (6)	−0.0057 (6)
C22	0.0415 (9)	0.0339 (9)	0.0318 (9)	0.0008 (7)	0.0040 (7)	−0.0044 (7)
C23	0.0465 (11)	0.0516 (11)	0.0336 (10)	0.0133 (9)	−0.0009 (8)	−0.0020 (8)
C24	0.0333 (9)	0.0767 (15)	0.0350 (10)	0.0043 (9)	−0.0031 (8)	−0.0111 (10)
C25	0.0340 (9)	0.0641 (13)	0.0479 (11)	−0.0133 (9)	0.0014 (8)	−0.0162 (10)
C26	0.0308 (8)	0.0389 (9)	0.0453 (10)	−0.0067 (7)	0.0012 (7)	−0.0066 (8)
C31	0.0263 (7)	0.0265 (7)	0.0324 (8)	−0.0051 (6)	0.0054 (6)	−0.0049 (6)
C32	0.0313 (8)	0.0427 (9)	0.0333 (9)	−0.0058 (7)	0.0034 (7)	−0.0087 (7)
C33	0.0479 (11)	0.0519 (11)	0.0355 (10)	−0.0082 (9)	0.0119 (8)	−0.0147 (8)
C34	0.0414 (10)	0.0536 (11)	0.0462 (11)	−0.0011 (8)	0.0195 (9)	−0.0098 (9)
C35	0.0274 (9)	0.0783 (15)	0.0539 (12)	−0.0019 (9)	0.0074 (8)	−0.0157 (11)
C36	0.0285 (9)	0.0632 (12)	0.0427 (10)	−0.0077 (8)	0.0024 (7)	−0.0167 (9)
C41	0.0309 (8)	0.0223 (7)	0.0228 (7)	−0.0006 (6)	0.0019 (6)	−0.0055 (6)
C42	0.0385 (9)	0.0286 (8)	0.0331 (9)	−0.0023 (6)	−0.0054 (7)	−0.0110 (7)
C43	0.0545 (11)	0.0266 (8)	0.0395 (10)	0.0015 (7)	−0.0046 (8)	−0.0146 (7)
C44	0.0431 (10)	0.0333 (9)	0.0378 (9)	0.0110 (7)	0.0022 (8)	−0.0099 (7)
C45	0.0295 (8)	0.0385 (9)	0.0420 (10)	0.0003 (7)	0.0021 (7)	−0.0050 (8)
C46	0.0323 (8)	0.0280 (8)	0.0368 (9)	−0.0044 (6)	0.0014 (7)	−0.0067 (7)
C51	0.0272 (7)	0.0208 (7)	0.0320 (8)	−0.0009 (6)	0.0008 (6)	−0.0027 (6)
C52	0.0372 (9)	0.0241 (7)	0.0385 (9)	−0.0036 (6)	0.0081 (7)	−0.0087 (7)
C53	0.0324 (9)	0.0288 (8)	0.0566 (12)	−0.0050 (7)	0.0129 (8)	−0.0094 (8)
C54	0.0313 (9)	0.0296 (8)	0.0584 (12)	−0.0061 (7)	−0.0049 (8)	0.0002 (8)
C55	0.0410 (10)	0.0333 (9)	0.0353 (9)	−0.0093 (7)	−0.0087 (7)	0.0032 (7)
C56	0.0347 (8)	0.0316 (8)	0.0296 (8)	−0.0061 (7)	0.0011 (7)	0.0003 (7)
N1	0.0397 (13)	0.0247 (10)	0.0343 (12)	−0.0076 (9)	0.0098 (11)	−0.0031 (8)
N1B	0.034 (3)	0.022 (2)	0.033 (3)	−0.0073 (18)	0.013 (2)	−0.0041 (18)
O1	0.0354 (12)	0.0214 (8)	0.0294 (11)	0.0051 (8)	0.0100 (9)	−0.0005 (7)
O1B	0.027 (2)	0.0205 (18)	0.038 (3)	0.0042 (17)	0.0124 (19)	0.0000 (17)
O2	0.0518 (8)	0.0506 (8)	0.0500 (8)	−0.0079 (6)	0.0098 (6)	−0.0001 (6)
P1	0.0266 (2)	0.02380 (19)	0.0298 (2)	−0.00413 (15)	0.00407 (15)	−0.00582 (16)
P2	0.0285 (2)	0.02239 (19)	0.0277 (2)	−0.00139 (14)	0.00210 (15)	−0.00764 (15)

Geometric parameters (Å, º) top

C1—C2	1.381 (2)	C16B—H16D	0.9900
C1—C6	1.394 (2)	C17B—C18	1.500 (5)
C1—N1	1.410 (2)	C17B—H17C	0.9900
C1—N1B	1.474 (3)	C17B—H17D	0.9900
C2—C3	1.377 (2)	C18—O2	1.408 (2)
C2—H2	0.9500	C18—H18A	0.9900
C3—C4	1.374 (2)	C18—H18B	0.9900
C3—H3	0.9500	C21—C26	1.391 (2)
C4—C5	1.395 (2)	C21—C22	1.392 (2)
C4—H4	0.9500	C21—P1	1.8250 (16)
C5—C6	1.372 (2)	C22—C23	1.384 (3)
C5—P1	1.8370 (15)	C22—H22	0.9500
C6—O1	1.402 (2)	C23—C24	1.366 (3)
C6—O1B	1.429 (3)	C23—H23	0.9500
C7—C8	1.373 (2)	C24—C25	1.380 (3)
C7—C12	1.394 (2)	C24—H24	0.9500
C7—O1B	1.408 (3)	C25—C26	1.386 (2)
C7—O1	1.415 (2)	C25—H25	0.9500
C8—C9	1.393 (2)	C26—H26	0.9500
C8—P2	1.8414 (15)	C31—C36	1.382 (2)
C9—C10	1.374 (2)	C31—C32	1.388 (2)
C9—H9	0.9500	C31—P1	1.8275 (16)
C10—C11	1.384 (2)	C32—C33	1.384 (2)
C10—H10	0.9500	C32—H32	0.9500
C11—C12	1.385 (2)	C33—C34	1.367 (3)
C11—H11	0.9500	C33—H33	0.9500
C12—N1	1.420 (2)	C34—C35	1.369 (3)
C12—N1B	1.464 (3)	C34—H34	0.9500
C13—N1	1.448 (3)	C35—C36	1.382 (3)
C13—C14	1.517 (3)	C35—H35	0.9500
C13—H13A	0.9900	C36—H36	0.9500
C13—H13B	0.9900	C41—C42	1.385 (2)
C14—C15	1.532 (3)	C41—C46	1.397 (2)
C14—H14A	0.9900	C41—P2	1.8264 (14)
C14—H14B	0.9900	C42—C43	1.393 (2)
C15—C16	1.510 (4)	C42—H42	0.9500
C15—H15A	0.9900	C43—C44	1.369 (3)
C15—H15B	0.9900	C43—H43	0.9500
C16—C17	1.508 (3)	C44—C45	1.374 (3)
C16—H16A	0.9900	C44—H44	0.9500
C16—H16B	0.9900	C45—C46	1.385 (2)
C17—C18	1.510 (3)	C45—H45	0.9500
C17—H17A	0.9900	C46—H46	0.9500
C17—H17B	0.9900	C51—C52	1.391 (2)
C13B—N1B	1.474 (4)	C51—C56	1.392 (2)
C13B—C14B	1.520 (5)	C51—P2	1.8284 (16)
C13B—H13C	0.9900	C52—C53	1.384 (2)
C13B—H13D	0.9900	C52—H52	0.9500
C14B—C15B	1.524 (5)	C53—C54	1.374 (3)
C14B—H14C	0.9900	C53—H53	0.9500
C14B—H14D	0.9900	C54—C55	1.380 (3)
C15B—C16B	1.508 (5)	C54—H54	0.9500
C15B—H15C	0.9900	C55—C56	1.383 (2)
C15B—H15D	0.9900	C55—H55	0.9500
C16B—C17B	1.512 (5)	C56—H56	0.9500
C16B—H16C	0.9900	O2—H2A	0.8400

C2—C1—C6	117.85 (15)	C16B—C17B—H17C	109.8
C2—C1—N1	122.95 (16)	C18—C17B—H17D	109.8
C6—C1—N1	118.37 (15)	C16B—C17B—H17D	109.8
C2—C1—N1B	119.71 (19)	H17C—C17B—H17D	108.2
C6—C1—N1B	117.95 (19)	O2—C18—C17B	105.1 (4)
C3—C2—C1	120.00 (15)	O2—C18—C17	107.4 (2)
C3—C2—H2	120.0	O2—C18—H18A	110.2
C1—C2—H2	120.0	C17B—C18—H18A	98.1
C4—C3—C2	121.30 (15)	C17—C18—H18A	110.2
C4—C3—H3	119.4	O2—C18—H18B	110.2
C2—C3—H3	119.4	C17B—C18—H18B	123.7
C3—C4—C5	120.09 (15)	C17—C18—H18B	110.2
C3—C4—H4	120.0	H18A—C18—H18B	108.5
C5—C4—H4	120.0	C26—C21—C22	118.56 (15)
C6—C5—C4	117.69 (14)	C26—C21—P1	123.49 (12)
C6—C5—P1	117.70 (11)	C22—C21—P1	117.93 (13)
C4—C5—P1	124.60 (12)	C23—C22—C21	120.57 (18)
C5—C6—C1	123.05 (14)	C23—C22—H22	119.7
C5—C6—O1	114.86 (15)	C21—C22—H22	119.7
C1—C6—O1	121.33 (15)	C24—C23—C22	120.29 (18)
C5—C6—O1B	115.83 (19)	C24—C23—H23	119.9
C1—C6—O1B	117.6 (2)	C22—C23—H23	119.9
C8—C7—C12	123.22 (14)	C23—C24—C25	120.13 (18)
C8—C7—O1B	115.96 (19)	C23—C24—H24	119.9
C12—C7—O1B	117.7 (2)	C25—C24—H24	119.9
C8—C7—O1	115.02 (15)	C24—C25—C26	120.11 (19)
C12—C7—O1	120.76 (15)	C24—C25—H25	119.9
C7—C8—C9	117.48 (14)	C26—C25—H25	119.9
C7—C8—P2	117.19 (11)	C25—C26—C21	120.32 (17)
C9—C8—P2	125.24 (11)	C25—C26—H26	119.8
C10—C9—C8	120.60 (15)	C21—C26—H26	119.8
C10—C9—H9	119.7	C36—C31—C32	118.01 (15)
C8—C9—H9	119.7	C36—C31—P1	116.18 (13)
C9—C10—C11	120.92 (15)	C32—C31—P1	125.79 (12)
C9—C10—H10	119.5	C33—C32—C31	120.40 (16)
C11—C10—H10	119.5	C33—C32—H32	119.8
C10—C11—C12	119.90 (15)	C31—C32—H32	119.8
C10—C11—H11	120.1	C34—C33—C32	120.68 (18)
C12—C11—H11	120.1	C34—C33—H33	119.7
C11—C12—C7	117.88 (14)	C32—C33—H33	119.7
C11—C12—N1	122.58 (16)	C33—C34—C35	119.63 (17)
C7—C12—N1	118.43 (16)	C33—C34—H34	120.2
C11—C12—N1B	119.68 (19)	C35—C34—H34	120.2
C7—C12—N1B	118.50 (19)	C34—C35—C36	120.06 (18)
N1—C13—C14	115.7 (2)	C34—C35—H35	120.0
N1—C13—H13A	108.4	C36—C35—H35	120.0
C14—C13—H13A	108.4	C35—C36—C31	121.21 (18)
N1—C13—H13B	108.4	C35—C36—H36	119.4
C14—C13—H13B	108.4	C31—C36—H36	119.4
H13A—C13—H13B	107.4	C42—C41—C46	118.02 (14)
C13—C14—C15	111.7 (2)	C42—C41—P2	125.36 (12)
C13—C14—H14A	109.3	C46—C41—P2	116.03 (11)
C15—C14—H14A	109.3	C41—C42—C43	120.58 (16)
C13—C14—H14B	109.3	C41—C42—H42	119.7
C15—C14—H14B	109.3	C43—C42—H42	119.7
H14A—C14—H14B	107.9	C44—C43—C42	120.48 (16)
C16—C15—C14	113.2 (2)	C44—C43—H43	119.8
C16—C15—H15A	108.9	C42—C43—H43	119.8
C14—C15—H15A	108.9	C43—C44—C45	119.83 (15)
C16—C15—H15B	108.9	C43—C44—H44	120.1
C14—C15—H15B	108.9	C45—C44—H44	120.1
H15A—C15—H15B	107.7	C44—C45—C46	120.17 (16)
C17—C16—C15	114.4 (3)	C44—C45—H45	119.9
C17—C16—H16A	108.7	C46—C45—H45	119.9
C15—C16—H16A	108.7	C45—C46—C41	120.91 (15)
C17—C16—H16B	108.7	C45—C46—H46	119.5
C15—C16—H16B	108.7	C41—C46—H46	119.5
H16A—C16—H16B	107.6	C52—C51—C56	118.34 (15)
C16—C17—C18	115.4 (3)	C52—C51—P2	116.88 (12)
C16—C17—H17A	108.4	C56—C51—P2	124.67 (12)
C18—C17—H17A	108.4	C53—C52—C51	120.89 (16)
C16—C17—H17B	108.4	C53—C52—H52	119.6
C18—C17—H17B	108.4	C51—C52—H52	119.6
H17A—C17—H17B	107.5	C54—C53—C52	119.95 (16)
N1B—C13B—C14B	111.0 (5)	C54—C53—H53	120.0
N1B—C13B—H13C	109.4	C52—C53—H53	120.0
C14B—C13B—H13C	109.4	C53—C54—C55	120.06 (16)
N1B—C13B—H13D	109.4	C53—C54—H54	120.0
C14B—C13B—H13D	109.4	C55—C54—H54	120.0
H13C—C13B—H13D	108.0	C54—C55—C56	120.15 (17)
C13B—C14B—C15B	113.8 (4)	C54—C55—H55	119.9
C13B—C14B—H14C	108.8	C56—C55—H55	119.9
C15B—C14B—H14C	108.8	C55—C56—C51	120.58 (16)
C13B—C14B—H14D	108.8	C55—C56—H56	119.7
C15B—C14B—H14D	108.8	C51—C56—H56	119.7
H14C—C14B—H14D	107.7	C1—N1—C12	116.48 (16)
C16B—C15B—C14B	114.8 (5)	C1—N1—C13	120.66 (18)
C16B—C15B—H15C	108.6	C12—N1—C13	121.43 (18)
C14B—C15B—H15C	108.6	C12—N1B—C13B	119.2 (3)
C16B—C15B—H15D	108.6	C12—N1B—C1	109.9 (3)
C14B—C15B—H15D	108.6	C13B—N1B—C1	118.8 (3)
H15C—C15B—H15D	107.5	C6—O1—C7	114.79 (16)
C15B—C16B—C17B	111.7 (5)	C7—O1B—C6	113.6 (3)
C15B—C16B—H16C	109.3	C18—O2—H2A	109.5
C17B—C16B—H16C	109.3	C21—P1—C31	102.21 (7)
C15B—C16B—H16D	109.3	C21—P1—C5	100.61 (7)
C17B—C16B—H16D	109.3	C31—P1—C5	100.22 (7)
H16C—C16B—H16D	107.9	C41—P2—C51	104.89 (7)
C18—C17B—C16B	109.4 (5)	C41—P2—C8	101.27 (7)
C18—C17B—H17C	109.8	C51—P2—C8	100.21 (7)

C6—C1—C2—C3	1.7 (3)	C43—C44—C45—C46	0.5 (3)
N1—C1—C2—C3	−167.7 (2)	C44—C45—C46—C41	0.0 (3)
N1B—C1—C2—C3	157.4 (3)	C42—C41—C46—C45	−0.4 (2)
C1—C2—C3—C4	−1.2 (3)	P2—C41—C46—C45	171.23 (13)
C2—C3—C4—C5	0.0 (3)	C56—C51—C52—C53	−1.5 (2)
C3—C4—C5—C6	0.7 (3)	P2—C51—C52—C53	174.79 (12)
C3—C4—C5—P1	−179.70 (14)	C51—C52—C53—C54	0.2 (2)
C4—C5—C6—C1	−0.1 (3)	C52—C53—C54—C55	1.5 (2)
P1—C5—C6—C1	−179.75 (15)	C53—C54—C55—C56	−1.8 (2)
C4—C5—C6—O1	170.02 (18)	C54—C55—C56—C51	0.4 (2)
P1—C5—C6—O1	−9.6 (2)	C52—C51—C56—C55	1.3 (2)
C4—C5—C6—O1B	−158.4 (3)	P2—C51—C56—C55	−174.75 (12)
P1—C5—C6—O1B	22.0 (3)	C2—C1—N1—C12	−164.7 (2)
C2—C1—C6—C5	−1.1 (3)	C6—C1—N1—C12	26.0 (3)
N1—C1—C6—C5	168.8 (2)	N1B—C1—N1—C12	−71.4 (3)
N1B—C1—C6—C5	−157.2 (3)	C2—C1—N1—C13	1.9 (4)
C2—C1—C6—O1	−170.58 (19)	C6—C1—N1—C13	−167.5 (2)
N1—C1—C6—O1	−0.7 (3)	N1B—C1—N1—C13	95.1 (5)
N1B—C1—C6—O1	33.3 (3)	C11—C12—N1—C1	166.2 (2)
C2—C1—C6—O1B	156.8 (3)	C7—C12—N1—C1	−26.1 (3)
N1—C1—C6—O1B	−33.3 (3)	N1B—C12—N1—C1	72.3 (3)
N1B—C1—C6—O1B	0.7 (4)	C11—C12—N1—C13	−0.2 (4)
C12—C7—C8—C9	−0.6 (3)	C7—C12—N1—C13	167.4 (2)
O1B—C7—C8—C9	159.0 (3)	N1B—C12—N1—C13	−94.1 (5)
O1—C7—C8—C9	−169.19 (17)	C14—C13—N1—C1	−81.6 (3)
C12—C7—C8—P2	176.11 (14)	C14—C13—N1—C12	84.3 (3)
O1B—C7—C8—P2	−24.3 (3)	C11—C12—N1B—C13B	−22.6 (6)
O1—C7—C8—P2	7.5 (2)	C7—C12—N1B—C13B	−179.8 (4)
C7—C8—C9—C10	−0.2 (2)	N1—C12—N1B—C13B	82.0 (6)
P2—C8—C9—C10	−176.62 (13)	C11—C12—N1B—C1	−164.8 (2)
C8—C9—C10—C11	0.3 (3)	C7—C12—N1B—C1	38.0 (4)
C9—C10—C11—C12	0.5 (3)	N1—C12—N1B—C1	−60.2 (3)
C10—C11—C12—C7	−1.3 (3)	C14B—C13B—N1B—C12	−74.1 (6)
C10—C11—C12—N1	166.5 (2)	C14B—C13B—N1B—C1	64.7 (6)
C10—C11—C12—N1B	−158.6 (3)	C2—C1—N1B—C12	166.4 (2)
C8—C7—C12—C11	1.3 (3)	C6—C1—N1B—C12	−37.9 (4)
O1B—C7—C12—C11	−158.0 (3)	N1—C1—N1B—C12	61.1 (3)
O1—C7—C12—C11	169.31 (19)	C2—C1—N1B—C13B	24.1 (6)
C8—C7—C12—N1	−166.94 (19)	C6—C1—N1B—C13B	179.8 (4)
O1B—C7—C12—N1	33.8 (3)	N1—C1—N1B—C13B	−81.2 (6)
O1—C7—C12—N1	1.1 (3)	C5—C6—O1—C7	165.88 (18)
C8—C7—C12—N1B	158.9 (3)	C1—C6—O1—C7	−23.8 (3)
O1B—C7—C12—N1B	−0.3 (4)	O1B—C6—O1—C7	67.1 (4)
O1—C7—C12—N1B	−33.1 (3)	C8—C7—O1—C6	−167.55 (18)
N1—C13—C14—C15	177.5 (2)	C12—C7—O1—C6	23.5 (3)
C13—C14—C15—C16	69.7 (3)	O1B—C7—O1—C6	−68.7 (4)
C14—C15—C16—C17	178.8 (3)	C8—C7—O1B—C6	160.1 (3)
C15—C16—C17—C18	−175.8 (4)	C12—C7—O1B—C6	−39.1 (5)
N1B—C13B—C14B—C15B	−177.6 (4)	O1—C7—O1B—C6	65.0 (4)
C13B—C14B—C15B—C16B	−79.7 (8)	C5—C6—O1B—C7	−161.6 (3)
C14B—C15B—C16B—C17B	−171.5 (8)	C1—C6—O1B—C7	38.9 (5)
C15B—C16B—C17B—C18	167.7 (8)	O1—C6—O1B—C7	−66.6 (3)
C16B—C17B—C18—O2	−178.7 (7)	C26—C21—P1—C31	−70.00 (15)
C16B—C17B—C18—C17	80.3 (18)	C22—C21—P1—C31	108.41 (13)
C16—C17—C18—O2	179.2 (3)	C26—C21—P1—C5	33.01 (15)
C16—C17—C18—C17B	−97.5 (19)	C22—C21—P1—C5	−148.57 (13)
C26—C21—C22—C23	0.0 (2)	C36—C31—P1—C21	−174.17 (13)
P1—C21—C22—C23	−178.52 (13)	C32—C31—P1—C21	4.35 (16)
C21—C22—C23—C24	0.0 (3)	C36—C31—P1—C5	82.51 (14)
C22—C23—C24—C25	1.0 (3)	C32—C31—P1—C5	−98.97 (15)
C23—C24—C25—C26	−1.9 (3)	C6—C5—P1—C21	79.94 (14)
C24—C25—C26—C21	1.9 (3)	C4—C5—P1—C21	−99.67 (15)
C22—C21—C26—C25	−0.9 (3)	C6—C5—P1—C31	−175.44 (13)
P1—C21—C26—C25	177.50 (14)	C4—C5—P1—C31	4.94 (16)
C36—C31—C32—C33	0.1 (3)	C42—C41—P2—C51	−8.63 (15)
P1—C31—C32—C33	−178.37 (14)	C46—C41—P2—C51	−179.58 (12)
C31—C32—C33—C34	−0.2 (3)	C42—C41—P2—C8	−112.52 (14)
C32—C33—C34—C35	−0.5 (3)	C46—C41—P2—C8	76.54 (13)
C33—C34—C35—C36	1.3 (3)	C52—C51—P2—C41	123.64 (12)
C34—C35—C36—C31	−1.4 (3)	C56—C51—P2—C41	−60.29 (14)
C32—C31—C36—C35	0.7 (3)	C52—C51—P2—C8	−131.68 (12)
P1—C31—C36—C35	179.31 (17)	C56—C51—P2—C8	44.39 (14)
C46—C41—C42—C43	0.4 (2)	C7—C8—P2—C41	−163.73 (13)
P2—C41—C42—C43	−170.36 (13)	C9—C8—P2—C41	12.66 (16)
C41—C42—C43—C44	0.0 (3)	C7—C8—P2—C51	88.68 (13)
C42—C43—C44—C45	−0.5 (3)	C9—C8—P2—C51	−94.93 (15)

Experimental details

Crystal data
Chemical formula	C₄₂H₃₉NO₂P₂
M_r	651.68
Crystal system, space group	Triclinic, P1
Temperature (K)	173
a, b, c (Å)	10.4258 (2), 11.1402 (3), 15.3590 (4)
α, β, γ (°)	75.777 (1), 88.583 (1), 79.453 (2)
V (Å³)	1699.60 (7)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.17
Crystal size (mm)	0.51 × 0.31 × 0.29

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	30269, 8211, 6458
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.660

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.122, 1.08
No. of reflections	8211
No. of parameters	489
No. of restraints	115
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.30

Computer programs: APEX2 (Bruker, 2005), SAINT-NT (Bruker, 2005), SHELXTL (Sheldrick, 2008), PLATON (Spek, 2003) and ORTEP-3 (Farrugia, 1997).

Acknowledgements

We thank Dr Manuel Fernandez for the data collection, and SASOL, THRIP and the University of KwaZulu-Natal for financial support.

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