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metal-organic papers

m74

Sommer and Rheingold [CuI(C

6H18N6P4)] doi:10.1107/S1600536805040791 Acta Cryst.(2006). E62, m74–m76 Acta Crystallographica Section E

Structure Reports

Online

ISSN 1600-5368

A copper(I) coordination polymer containing an

adamantane P–N cage ligand

Roger D. Sommera* and Arnold L. Rheingoldb

a

DePaul University, Department of Chemistry, 1036 W. Belden Ave., Chicago, IL 60614-3251, USA, andbDepartment of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA

Correspondence e-mail: rsommer@condor.depaul.edu

Key indicators

Single-crystal X-ray study

T= 100 K

Mean(C–N) = 0.003 A˚

Rfactor = 0.027

wRfactor = 0.069

Data-to-parameter ratio = 21.3

For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.

#2006 International Union of Crystallography

Printed in Great Britain – all rights reserved

The tetradentate non-chelating ligand 2,4,6,8,9,10-hexa-methyl-2,4,6,8,9,10-hexaaza-1,3,5,7-tetraphosphaadamantane, P4(NCH3)6, reacts with one equivalent of cuprous iodide to

yield the title coordination polymer, catena -poly[[iodo-copper(I)]- -2,4,6,8,9,10-hexamethyl-2,4,6,8,9,10-hexaaza-1,3,5,7-tetraphosphaadamantane-2

P1:P3], [CuI(C6H18N6P4)]n.

The polymer is linked through P—Cu coordination at two vertices of the cage. The CuI ions have a trigonal–planar geometry, coordinated by P atoms from two different ligands and the iodide. This structure represents the first crystal-lographically characterized coordination compound of this cage ligand.

Comment

Spectroscopic studies have shown that the cage compound P4(NCH3)6can coordinate up to four Lewis acids [Ni(CO)3, or

BH3], one at each P vertex (Reiss & Van Wazer, 1967, 1968).

Crystallographic studies of chalcogenide derivatives P4(NCH3)6Xn(X= O or S,n= 1–4) have also been reported

(Casabiancaet al., 1978; Cottonet al., 1982, 1983). To date, no crystallographic characterization has been carried out on the coordination complexes of P4(NCH3)6. We have found this

ligand to be effective at coordinating soft metal ions and here report the crystal structure of the coordination polymer [P4(NCH3)6CuI]n, (I). The Cu—P bond lengths are consistent

with other known structures of CuI with P—N ligands at 2.2434 (8) and 2.2390 (8) A˚ for Cu1—P1 and Cu1—P4i, respectively [symmetry code: (i) 2 x, y + 1

2, z + 1 2]. IR

spectroscopy of solid (I) as a KBr pellet indicated a shift in

(P—N) from 825 cm1 for the uncomplexed ligand to 853 cm1, with shoulders at 871 and 880 cm1, for the complexed ligand. This shift is consistent with previous studies of the chalcogenide derivatives of the ligand (Casabianca et al., 1977).

It is interesting to compare this structure with the CuI complex formed by hexamethylphosphorus triamide, the

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monomeric analog of P4(NCH3)6. The HMPT complex of Cu I

forms a cube-shaped Cu4I4 core with the P ligands bound

peripherally to the four Cu vertices (Arkhireevaet al., 1990) The crystallographic cone angle for the cage ligand is esti-mated to be 140, roughly 10 larger than that of HMPT

(Mueller & Mingos, 1995).

The internal structure of the cage shows minor distortions to the P—N bond lengths typical of this family of compounds (Cottonet al., 1978, 1982, 1983). The bonds lengths for P atoms bonded to Cu (P1 and P4) are consistently shorter than those for non-coordinated P atoms. The geometry around the N atoms in the cage is roughly planar. The sum of angles around N atoms ranges from 356 to 346. The least planar N atoms are

at positions where this distortion relieves crowding between methyl groups of neighboring cages. The P P distances within the cage range from 2.975 to 3.037 A˚ .

Experimental

Manipulations were carried out using standard Schlenck techniques. The title compound was prepared by cannula addition of cuprous iodide (0.050 g) in freshly distilled acetonitrile (20 ml) to a similarly prepared solution of P4(NCH3)6 (0.105 g). Some precipitation

occurred immediately. The reaction flask was sealed under nitrogen and refrigerated at 277 K. Crystal formation was observed after two days. The white blocks are air stable over a period of one week.

Crystal data

[CuI(C6H18N6P4)]

Mr= 488.58

Monoclinic,P21=c

a= 8.4321 (5) A˚

b= 11.6068 (7) A˚

c= 16.2351 (10) A˚

= 94.863 (1)

V= 1583.20 (17) A˚3

Z= 4

Dx= 2.05 Mg m

3

MoKradiation Cell parameters from 6312

reflections

= 2.4–27.5

= 3.73 mm1

T= 100 (2) K Block, colorless 0.190.160.14 mm

Data collection

Bruker SMART CCD area-detector diffractometer

’and!scans

Absorption correction: multi-scan (SADABS; Sheldrick, 1996)

Tmin= 0.474,Tmax= 0.594

9801 measured reflections

3605 independent reflections 3234 reflections withI> 2(I)

Rint= 0.022 max= 27.5

h=10!8

k=14!15

l=21!20

Refinement

Refinement onF2 R[F2> 2(F2)] = 0.027

wR(F2) = 0.069

S= 1.03 3605 reflections 169 parameters

H-atom parameters constrained

w= 1/[2

(Fo2) + (0.0262P)2

+ 1.8652P]

whereP= (Fo2+ 2Fc2)/3

(/)max= 0.001

max= 1.23 e A˚

3

min=0.71 e A˚

3

metal-organic papers

Acta Cryst.(2006). E62, m74–m76 Sommer and Rheingold [CuI(C

[image:2.610.89.223.72.277.2]

6H18N6P4)]

m75

Figure 3

[image:2.610.310.566.73.206.2]

View along thebaxis of P4(NCH3)6CuIn. Displacement ellipsoids are drawn at the 50% probability level. H atoms have been omitted for clarity.

Figure 2

Displacement ellipsoid plot of [P4(NCH3)6CuI]n(n= 3). Displacement ellipsoids are drawn at the 50% probability level. H atoms have been omitted for clarity.

Figure 1

[image:2.610.315.565.255.537.2]
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H atoms were placed at appropriate positions (C—H = 0.98 A˚ ) and refined withUiso(H) = 1.2Ueq(C). The largest peak of residual

elec-tron density is 1.02 A˚ from C4. The position of atoms C2 and C4 in a relatively open region of space in the crystal structure allows greater vibrational motion, resulting in elongated displacement ellipsoids for these atoms. Modeling of C4 as a disordered methyl group with refined occupancy gave no improvement in structure refinement.

Data collection:SMART(Bruker, 2001); cell refinement:SAINT

(Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97(Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics:

ORTEP-3(Farrugia, 1997) andPOV-Ray(Persistence of Vision Pty. Ltd, 2004); software used to prepare material for publication:WinGX

(Farrugia, 1999).

RDS would like to thank Dr Bruce Noll for useful discussions.

References

Arkhireeva, T. M., Bulychev, B. M., Sizov, A. I., Sokolova, T. A., Belsky, V. K. & Soloveichik, G. L. (1990).Inorg. Chim. Acta,169, 109–118.

Bruker (2001).SMARTandSAINT. Bruker AXS Inc., Madison Wisconsin, USA.

Casabianca, F., Cotton, F. A., Riess, J. G., Rice, C. E. & Stults, B. R. (1978).

Inorg. Chem.17, 3521–3525.

Casabianca, F., Pinkerton, A. A. & Riess, J. G. (1977).Inorg. Chem.16, 864– 867.

Cotton, F. A., Riess, J. G., Rice, C. E. & Stults, B. R. (1978).Inorg. Chem.17, 3232–3236.

Cotton, F. A., Riess, J. G., Rice, C. E. & Stults, B. R. (1982).Inorg. Chem.21, 3123–3126.

Cotton, F. A., Riess, J. G. & Stults, B. R. (1983).Inorg. Chem.22, 133–136. Farrugia, L. J. (1997).J. Appl. Cryst.30, 565.

Farrugia, L. J. (1999).J. Appl. Cryst.32, 837–838.

Mueller, T. E. & Mingos, D. M. P. (1995).Transition Met. Chem.20, 533–539. Persistence of Vision Pty. Ltd (2004). POV-Ray. Version 3.6. http://

www.povray.org/download/.

Reiss, J. G. & Van Wazer, J. R. (1967).J. Organomet. Chem.8, 347–353. Reiss, J. G. & Van Wazer, J. R. (1968).Bull. Chem. Soc. Fr.8, 3087–3094. Sheldrick, G. M. (1996).SADABS. University of Gottingen, Germany. Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of

Go¨ttingen, Germany.

metal-organic papers

m76

Sommer and Rheingold [CuI(C

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Acta Cryst. (2006). E62, m74–m76

supporting information

Acta Cryst. (2006). E62, m74–m76 [doi:10.1107/S1600536805040791]

A copper(I) coordination polymer containing an adamantane P

N cage ligand

Roger D. Sommer and Arnold L. Rheingold

S1. Comment

Spectroscopic studies have shown that the cage compound P4(NCH3)6 can coordinate up to four Lewis acids [Ni(CO)3, or

BH3], one at each P vertex (Riess or Reiss & Van Wazer, 1967, 1968). Crystallographic studies of chalcogenide

derivatives P4(NCH3)6Xn (X = O or S, n = 1–4) have also been reported (Casabianca et al., 1978; Cotton et al., 1982,

1983). To date, no crystallographic characterization has been carried out on the coordiation complexes of P4(NCH3)6. We

have found this ligand to be effective at coordinating soft metal ions and here report the crystal structure of the

coordination polymer [P4(NCH3)6CuI]n, (I). The Cu—P bond lengths are consistent with other known structures of CuI

with P—N ligands at 2.2434 (8) and 2.2390 (8) Å for Cu1—P1 and Cu1—P4i, respectively. IR spectroscopy of solid (I)

as a KBr pellet indicated a shift in νP—N from 825 cm−1 for the uncomplexed ligand to 853 cm−1 with shoulders at 871

and 880 cm−1 for the complexed ligand. This shift is consistent with previous studies of the chalcogenide derivatives of

the ligand. (Casabianca et al., 1977)

It is interesting to compare this structure with the CuI complex formed by hexamethylphosphorustriamide (HMPT), the

monomeric analog of P4(NCH3)6. The HMPT complex of CuI forms a cube-shaped Cu4I4 core with the P ligands bound

peripherally to the four Cu vertices (Arkhireeva et al., 1990) The crystallographic cone angle for the cage ligand is

estimated to be 140°, roughly 10° larger than that of HMPT (Mueller & Mingos, 1995).

The internal structure of the cage shows minor distortions to the P—N bond lengths typical of this family of compounds

(Cotton et al., 1978, 1982, 1983). The P—N bonds lengths for P bonded to Cu (P1 and P4) are consistently shorter than

those for non-coordinated P atoms. The geometry around the N atoms in the cage is roughly planar. The sum of angles

around N atoms ranges from 356 to 346°. The least planar N atoms are at positions where this distortion relieves

crowding between methyl groups of neighboring cages. The P—P distances within the cage range from 2.975 to 3.037 Å.

S2. Experimental

Manipulations were carried out using standard Schlenck technique. The title compound was prepared by cannula addition

of cuprous iodide (0.050 g) in freshly distilled acetonitrile (20 ml) to a similarly prepared solution of P4(NCH3)6 (0.105

g). Some precipitation occurred immediately. The reaction flask was sealed under nitrogen and refrigerated at 277 K.

Crystal formation was observed after two days. The white blocks are air stable over a period of one week.

S3. Refinement

Hydrogen atoms were placed at appropriate positions (C—H = 0.98 Å) and refined with a riding isotropic displacement

parameter 1.2 times that of the parent atom. The largest peak of residual electron density is 1.02 Å from C4. The position

of atoms C2 and C4 in a relatively open region of space in the crystal allows greater vibrational motion resulting in

elongated thermal ellipsoids for these atoms. Modeling of C4 as a disordered methyl group using a refined free variable

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[image:5.610.149.460.74.523.2]

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Acta Cryst. (2006). E62, m74–m76

Figure 1

Displacement ellipsoid plot of monomer unit. Displacement ellipsoids are drawn at the 50% probability level. H atoms

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[image:6.610.128.484.69.255.2]

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Acta Cryst. (2006). E62, m74–m76

Figure 2

Displacement ellipsoid plot of [P4(NCH3)6CuI]n (n = 3). Displacement ellipsoids are drawn at the 50% probability level.

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[image:7.610.132.485.67.468.2]

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Acta Cryst. (2006). E62, m74–m76

Figure 3

View along the b axis of P4(NCH3)6CuIn. Displacment ellipsoids are drawn at the 50% probability level. H atoms have

been omitted for clarity.

catena-poly[[iodocopper(I)]-µ-2,4,6,8,9,10-hexamethyl-2,4,6,8,9,10-hexaaza-

1,3,5,7-tetraphosphaadamantane-κ2P1:P3]

Crystal data [CuI(C6H18N6P4)]

Mr = 488.58

Monoclinic, P21/c

a = 8.4321 (5) Å b = 11.6068 (7) Å c = 16.2351 (10) Å β = 94.863 (1)° V = 1583.20 (17) Å3

Z = 4

F(000) = 952 Dx = 2.05 Mg m−3

Mo radiation, λ = 0.71073 Å Cell parameters from 6312 reflections θ = 2.4–27.5°

µ = 3.73 mm−1

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Acta Cryst. (2006). E62, m74–m76

Data collection

Bruker SMART CCD area-detector diffractometer

Radiation source: fine-focus sealed tube Graphite monochromator

φ and ω scans

Absorption correction: multi-scan

(SADABS; Sheldrick, 1996)

Tmin = 0.474, Tmax = 0.594

9801 measured reflections 3605 independent reflections 3234 reflections with I > 2σ(I) Rint = 0.022

θmax = 27.5°, θmin = 2.2°

h = −10→8 k = −14→15 l = −21→20

Refinement Refinement on F2

Least-squares matrix: full R[F2 > 2σ(F2)] = 0.027

wR(F2) = 0.069

S = 1.03 3602 reflections 169 parameters

0 restraints

H-atom parameters constrained w = 1/[σ2(F

o2) + (0.0262P)2 + 1.8652P]

where P = (Fo2 + 2Fc2)/3

(Δ/σ)max = 0.001

Δρmax = 1.23 e Å−3

Δρmin = −0.71 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.

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

x y z Uiso*/Ueq

I1 0.72936 (2) 0.579312 (15) 0.069568 (12) 0.02046 (6)

Cu1 0.87384 (4) 0.71572 (3) 0.17027 (2) 0.01346 (8)

P1 1.04422 (8) 0.63047 (6) 0.26493 (4) 0.01229 (14)

P2 1.18719 (9) 0.62129 (6) 0.43828 (5) 0.01779 (15)

P3 1.39471 (8) 0.58751 (6) 0.29620 (5) 0.01705 (15)

P4 1.16248 (8) 0.40671 (6) 0.33530 (4) 0.01180 (14)

N1 1.0492 (3) 0.67457 (19) 0.36375 (14) 0.0160 (5)

N2 1.3636 (3) 0.63634 (19) 0.39244 (15) 0.0181 (5)

N3 1.2322 (3) 0.64358 (19) 0.23728 (14) 0.0156 (5)

N4 1.3376 (3) 0.44569 (19) 0.30059 (15) 0.0158 (5)

N5 1.1578 (3) 0.47475 (19) 0.42786 (14) 0.0151 (5)

N6 1.0262 (2) 0.48477 (18) 0.27578 (13) 0.0120 (4)

C1 0.9770 (4) 0.7866 (2) 0.38322 (18) 0.0205 (6)

H1A 1.0461 0.8494 0.3675 0.031*

H1B 0.9649 0.7909 0.4426 0.031*

H1C 0.8724 0.7938 0.3524 0.031*

C2 1.4423 (4) 0.7485 (3) 0.4131 (2) 0.0286 (7)

H2A 1.5502 0.7479 0.395 0.043*

H2B 1.4477 0.7608 0.473 0.043*

H2C 1.3809 0.8109 0.385 0.043*

C3 1.2445 (4) 0.6293 (3) 0.14700 (18) 0.0231 (6)

H3A 1.2028 0.5535 0.1295 0.035*

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H3C 1.1824 0.6896 0.1169 0.035*

C4 1.4647 (4) 0.3604 (3) 0.3021 (3) 0.0486 (11)

H4A 1.5276 0.3634 0.3557 0.073*

H4B 1.5334 0.377 0.2579 0.073*

H4C 1.4183 0.2834 0.2939 0.073*

C5 1.2448 (4) 0.4127 (2) 0.49809 (18) 0.0216 (6)

H5A 1.234 0.3294 0.4894 0.032*

H5B 1.1999 0.4339 0.5497 0.032*

H5C 1.3576 0.434 0.5014 0.032*

C6 0.8605 (3) 0.4478 (2) 0.28647 (18) 0.0154 (5)

H6A 0.8445 0.3689 0.2659 0.023*

H6B 0.7857 0.4996 0.2553 0.023*

H6C 0.8419 0.4506 0.3452 0.023*

Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23

I1 0.02546 (11) 0.01183 (10) 0.02227 (11) −0.00239 (7) −0.00864 (7) −0.00094 (7)

Cu1 0.01347 (16) 0.00879 (16) 0.01740 (17) 0.00064 (12) −0.00299 (12) 0.00017 (12)

P1 0.0122 (3) 0.0086 (3) 0.0155 (3) 0.0002 (2) −0.0019 (2) −0.0004 (2)

P2 0.0240 (4) 0.0112 (3) 0.0168 (4) 0.0015 (3) −0.0061 (3) −0.0028 (3)

P3 0.0119 (3) 0.0109 (3) 0.0277 (4) −0.0014 (2) −0.0024 (3) 0.0019 (3)

P4 0.0115 (3) 0.0088 (3) 0.0146 (3) −0.0001 (2) −0.0019 (2) −0.0005 (2)

N1 0.0195 (12) 0.0114 (11) 0.0165 (12) 0.0032 (9) −0.0024 (9) −0.0027 (9)

N2 0.0172 (11) 0.0102 (11) 0.0250 (13) −0.0022 (9) −0.0091 (9) −0.0009 (9)

N3 0.0136 (11) 0.0141 (11) 0.0184 (12) 0.0000 (8) −0.0016 (9) 0.0010 (9)

N4 0.0124 (11) 0.0084 (10) 0.0263 (13) 0.0000 (8) 0.0007 (9) 0.0008 (9)

N5 0.0205 (12) 0.0115 (11) 0.0127 (11) 0.0011 (9) −0.0032 (9) −0.0001 (8)

N6 0.0105 (10) 0.0089 (10) 0.0161 (11) −0.0003 (8) −0.0015 (8) 0.0002 (8)

C1 0.0289 (16) 0.0109 (13) 0.0219 (15) 0.0061 (11) 0.0029 (12) −0.0008 (11)

C2 0.0264 (17) 0.0123 (14) 0.044 (2) −0.0054 (12) −0.0125 (14) −0.0048 (13)

C3 0.0217 (15) 0.0255 (16) 0.0225 (15) 0.0013 (12) 0.0042 (12) 0.0030 (12)

C4 0.0276 (19) 0.0192 (18) 0.102 (4) 0.0005 (14) 0.025 (2) −0.0033 (19)

C5 0.0313 (16) 0.0172 (14) 0.0150 (14) 0.0008 (12) −0.0059 (12) 0.0015 (11)

C6 0.0122 (12) 0.0122 (13) 0.0217 (14) −0.0007 (10) 0.0009 (10) −0.0007 (10)

Geometric parameters (Å, º)

I1—Cu1 2.5151 (4) N5—C5 1.488 (3)

Cu1—P4i 2.2387 (7) N6—C6 1.486 (3)

Cu1—P1 2.2430 (7) C1—H1A 0.98

P1—N1 1.681 (2) C1—H1B 0.98

P1—N3 1.691 (2) C1—H1C 0.98

P1—N6 1.708 (2) C2—H2A 0.98

P2—N1 1.721 (2) C2—H2B 0.98

P2—N5 1.725 (2) C2—H2C 0.98

P2—N2 1.728 (3) C3—H3A 0.98

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Acta Cryst. (2006). E62, m74–m76

P3—N4 1.718 (2) C3—H3C 0.98

P3—N3 1.730 (2) C4—H4A 0.98

P4—N4 1.686 (2) C4—H4B 0.98

P4—N6 1.699 (2) C4—H4C 0.98

P4—N5 1.701 (2) C5—H5A 0.98

P4—Cu1ii 2.2387 (7) C5—H5B 0.98

N1—C1 1.481 (3) C5—H5C 0.98

N2—C2 1.487 (3) C6—H6A 0.98

N3—C3 1.487 (4) C6—H6B 0.98

N4—C4 1.458 (4) C6—H6C 0.98

P4i—Cu1—P1 122.82 (3) P4—N6—P1 121.66 (13)

P4i—Cu1—I1 122.69 (2) N1—C1—H1A 109.5

P1—Cu1—I1 114.49 (2) N1—C1—H1B 109.5

N1—P1—N3 106.14 (12) H1A—C1—H1B 109.5

N1—P1—N6 101.44 (11) N1—C1—H1C 109.5

N3—P1—N6 102.12 (11) H1A—C1—H1C 109.5

N1—P1—Cu1 118.83 (8) H1B—C1—H1C 109.5

N3—P1—Cu1 109.81 (8) N2—C2—H2A 109.5

N6—P1—Cu1 116.74 (8) N2—C2—H2B 109.5

N1—P2—N5 101.67 (11) H2A—C2—H2B 109.5

N1—P2—N2 102.50 (12) N2—C2—H2C 109.5

N5—P2—N2 100.33 (11) H2A—C2—H2C 109.5

N2—P3—N4 102.43 (12) H2B—C2—H2C 109.5

N2—P3—N3 101.87 (11) N3—C3—H3A 109.5

N4—P3—N3 99.89 (11) N3—C3—H3B 109.5

N4—P4—N6 103.64 (11) H3A—C3—H3B 109.5

N4—P4—N5 104.91 (12) N3—C3—H3C 109.5

N6—P4—N5 100.93 (11) H3A—C3—H3C 109.5

N4—P4—Cu1ii 111.89 (8) H3B—C3—H3C 109.5

N6—P4—Cu1ii 114.93 (8) N4—C4—H4A 109.5

N5—P4—Cu1ii 118.82 (8) N4—C4—H4B 109.5

C1—N1—P1 119.58 (18) H4A—C4—H4B 109.5

C1—N1—P2 115.53 (18) N4—C4—H4C 109.5

P1—N1—P2 121.47 (14) H4A—C4—H4C 109.5

C2—N2—P3 113.5 (2) H4B—C4—H4C 109.5

C2—N2—P2 112.0 (2) N5—C5—H5A 109.5

P3—N2—P2 124.52 (13) N5—C5—H5B 109.5

C3—N3—P1 113.37 (18) H5A—C5—H5B 109.5

C3—N3—P3 112.63 (18) N5—C5—H5C 109.5

P1—N3—P3 122.39 (14) H5A—C5—H5C 109.5

C4—N4—P4 118.4 (2) H5B—C5—H5C 109.5

C4—N4—P3 116.3 (2) N6—C6—H6A 109.5

P4—N4—P3 121.83 (13) N6—C6—H6B 109.5

C5—N5—P4 113.91 (18) H6A—C6—H6B 109.5

C5—N5—P2 110.15 (17) N6—C6—H6C 109.5

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Acta Cryst. (2006). E62, m74–m76

C6—N6—P4 112.14 (17) H6B—C6—H6C 109.5

C6—N6—P1 112.98 (16)

Figure

Figure 3
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References

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