Crystal structure of cyclo-bis­(μ4-2,2-di­allyl­malonato-κ6O1,O3:O3:O1′,O3′:O1′)tetra­kis­(triphenyl­phosphane-κP)tetra­silver(I)

Frenzel, P.; Jakob, A.; Schaarschmidt, D.; Rüffer, T.; Lang, H.

doi:10.1107/S1600536814019394

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Volume 70| Part 10| October 2014| Pages 174-177

doi:10.1107/S1600536814019394

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Crystal structure of cyclo-bis(μ₄-2,2-diallylmalonato-κ⁶O¹,O³:O³:O^1′,O^3′:O^1′)tetrakis(triphenylphosphane-κP)tetrasilver(I)

Peter Frenzel,^a Alexander Jakob,^a Dieter Schaarschmidt,^a Tobias Rüffer ^a and Heinrich Lang ^a ^*

^aTechnische Universität Chemnitz, Faculty of Natural Sciences, Institute of Chemistry, Inorganic Chemistry, 09107 Chemnitz, Germany
^*Correspondence e-mail: heinrich.lang@chemie.tu-chemnitz.de

Edited by M. Weil, Vienna University of Technology, Austria (Received 8 August 2014; accepted 27 August 2014; online 10 September 2014)

In the tetranuclear molecule of the title compound, [Ag₄(C₉H₁₀O₄)₂(C₁₈H₁₅P)₄], the Ag^I ion is coordinated by one P and three O atoms in a considerably distorted tetrahedral environment. The two 2,2-diallylmalonate anions bridge four Ag^I ions in a μ₄-(κ⁶O¹,O³:O³:O^1′,O^3′:O^1′) mode, setting up an Ag₄O₈P₄ core (point group symmetry -4..) of corner-sharing tetrahedra. The shortest intramolecular Ag⋯Ag distance of 3.9510 (3) Å reveals that no direct d¹⁰⋯d¹⁰ interactions are present. Four weak intramolecular C—H⋯O hydrogen bonds are observed in the crystal structure of the title compound, which most likely stabilize the tetranuclear silver core.

Keywords: crystal structure; silver(I); malonate ligand; phosphane ligand; Ag₄O₈P₄ core.

CCDC reference: 1021407

1. Chemical context

Silver(I) carboxylates of general type [AgO₂CR]_n (n is the degree of aggregation) are of interest due to their versatile structures in the solid state and in solution, their synthetic methodologies and their manifold reaction behavior (see, for example: Schliebe et al., 2013 ; Jahn et al., 2010 ; Wang et al., 2008 ; Fernández et al., 2007 ; Olson et al., 2006 ; Szymańska et al., 2007 ). These metal-organic complexes are of importance not only in the field of basic research but also in multipurpose applications including, for example, metallization processes for micro- and nano-structured new materials in electronic systems and devices (e.g. using chemical vapour deposition, CVD), since silver possesses the highest electrical conductivity of any element (Jakob et al., 2010 ; Lang & Dietrich, 2013 ), catalytic processes (Steffan et al., 2009 ) and their use in biological studies (Djokić, 2008 ; Zhu et al., 2003 ).

The CVD process requires metal precursors possessing high vapour pressures. On a molecular level this is typically achieved by designing low aggregated metal compounds. In the case of silver, this can be realized by the use of phosphanes as a Lewis base; however, the concomitant increase of the molecular weight of the transition metal complex may decrease its vapour pressure. Circumventing this difficulty, we have investigated the use of olefines as ligands for silver(I) carboxylates, in which the olefin is covalently bonded to the carboxylate. In the context of this approach, the title compound [{(Ph₃P)Ag}₄{(O₂C)₂C(CH₂CH=CH₂)₂}₂], (I), was obtained by the reaction of the silver salt of 2,2-diallylmalonic acid with triphenylphosphane.

2. Structural commentary

The asymmetric unit of (I) contains one quarter of the molecule which is completed by application of a fourfold screw axis as the symmetry element. The resulting tetranuclear silver core is decorated by four triphenylphosphane ligands, whereby the metal ions are bridged by two 2,2-diallylmalonate anions in a μ₄-(κ⁶O¹,O³:O³:O^1′,O^3′:O^1′) mode (Fig. 1). There is no example in the literature of a transition metal malonate displaying this type of coordination. The environment around silver, set up by one phosphorus and three oxygen atoms, is best described as distorted tetrahedral. Ag1 is oriented slightly above the plane of O1, P1 and O2ⁱⁱ [distance 0.2911 (10) Å], which is supported by the respective bond angles around Ag1 (Table 1) summing up to 354.3°. The O—Ag1—P1 angles are substantially larger than the O—Ag1—O angles, which may be attributed to the chelating coordination of the malonate ligands and the bulkiness of the triphenylphosphane ligand. The Ag—O bond lengths are more than 0.2 Å shorter for the two oxygen atoms of the aforementioned plane than for the third apical oxygen atom (Table 1). However, the values are in the expected range for Ag—O bonds in silver carboxylates.

Table 1
Selected bond lengths (Å) and bond angles (°)

Ag1—O1	2.323 (2)	O1—Ag1—O2ⁱ	82.45 (7)
Ag1—P1	2.3483 (8)	O1—Ag1—O2ⁱⁱ	90.28 (8)
Ag1—O2ⁱ	2.592 (2)	P1—Ag1—O2ⁱ	112.26 (5)
Ag1—O2ⁱⁱ	2.344 (2)	P1—Ag1—O2ⁱⁱ	115.95 (6)
O1—Ag1—P1	148.09 (6)	O2ⁱ—Ag1—O2ⁱⁱ	92.63 (10)
Symmetry codes: (i) −x + 1, −y + 1, z; (ii) −y + 1, x, −z + 2.

Figure 1
The Ag₄O₈P₄ core of the title compound with surrounding atoms. Displacement ellipsoids are displayed at the 50% probability level. The carbon atoms of the phenyl substituents except the ipso-carbon atoms and all hydrogen atoms have been omitted for clarity. [Symmetry codes: (A) –x + 1, –y + 1, z; (B) y, –x + 1, –z + 2; (C) –y + 1, x, –z + 2.]

The cyclic corner-sharing arrangement of the described O₃P tetrahedra gives the tetranuclear structure of (I) (Fig. 2). The four silver ions are oriented in a butterfly-like arrangement, which delimits the title compound from Ag₄O₄ heterocubanes (Jakob et al., 2011 ; Zhang et al., 2008 , Kühnert et al., 2007 ) in which the four silver ions form a tetrahedron. In contrast, there are some similarities with [bis(1,8-naphthalenedicarboxylato)][tetrakis(triphenylphosphane)silver(I)] (van der Ploeg et al., 1979 ); however, in the structure of this compound one silver ion is pentacoordinated.

Figure 2
Structure fragment showing the cyclic corner-sharing arrangement of the AgO₃P polyhedra giving the tetranuclear silver core of composition Ag₄O₈P₄.

3. Supramolecular features

Four weak intramolecular C—H⋯O hydrogen bonds (Steiner, 2002 ) are observed in the crystal structure of (I) (Table 2), which most likely stabilize the silver core.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C13—H13⋯O2ⁱ	0.93	2.51	3.351 (4)	150
Symmetry code: (i) -x+1, -y+1, z.

In contrast to iridium and platinum complexes of 2,2-diallylmalonic acid and derivatives thereof, the C=C double bond does not coordinate the transition metal in (I). Furthermore, no obvious π–π stacking interactions are observed between the allyl and the phenyl substituents. Therefore, the packing seems to be dominated by dispersion forces (Fig. 3).

Figure 3
Packing diagram of the title compound along the c axis; voids in the structure are represented by red spheres [drawn using the CAVITYPLOT routine in PLATON (Spek, 2009

)]. The hydrogen atoms have been omitted for clarity. Colour code: black (C), red (O), yellow (P), green (Ag).

4. Database survey

2,2-Diallylmalonic acid and derivatives thereof have only been used as ligands in four mononuclear platinum and one iridium complex, in which coordination of the transition metal occurs either through (O,O′)-, (O,alkene)- or (alkene,alkene′)-chelation (Berthon-Gelloz et al., 2007 ; Makino et al., 2004 ; Jung et al., 1999 ; Lee et al., 1999 ). To the best of our knowledge, no diallylmalonate silver(I) compounds have been described in the literature so far.

5. Synthesis and crystallization

Complex [{(Ph₃P)Ag}₄{(O₂C)₂C(CH₂CH=CH₂)₂}₂] was prepared by the addition of PPh₃ (132 mg, 0.503 mmol) to a suspension of [(AgO₂C)₂C(CH₂CH=CH₂)₂] (100 mg, 0.251 mmol) in dichloromethane (30 ml) at 273 K. After stirring for 2 h at this temperature, the reaction mixture was filtered through a pad of celite. Afterwards, all volatiles were removed in oil-pump vacuum, and (I) was obtained as a pale-grey solid. Colourless crystals of (I) were obtained by solvent diffusion of a chloroform solution of (I) against pentane at ambient temperature. Yield: 230 mg (0.125 mmol, 99% based on [(AgO₂C)₂C(CH₂CH=CH₂)₂]).

Analysis calculated for C₉₀H₈₀Ag₄O₈P₄ (1844.96): C 58.59, H 4.37. Found: C 58.53, H 4.34. ¹H NMR (500 MHz, CDCl₃, 298 K, ppm): δ = 2.79 (d, 8H, ³J_HH = 6.5 Hz, CH₂CH=CH₂), 4.97 (d, 4H, ³J_HH = 10.2 Hz, CH₂CH=CH₂), 5.03 (d, 4H, ³J_HH = 17.1 Hz, CH₂CH=CH₂), 5.90 (m, 4H, CH₂CH=CH₂), 7.30–7.51 (m, 60H, C₆H₅). ³¹P{¹H} NMR (203 MHz, CDCl₃, 298 K, ppm): δ = 15.7 (d, ¹J_AgP = 680 Hz). IR (KBr, cm⁻¹): ν = 1637 (w, C=C), 1559 (vs, C=O), 1440 (vs, P—Ph), 692 (vs), 521 (vs).

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3. C-bonded H atoms were placed in calculated positions and constrained to ride on their parent atoms, with U_iso(H) = 1.2U_eq(C) and a C—H distance of 0.93 Å for aromatic and vinylic as well as 0.97 Å for methylene protons. The unit cell contains two voids of 34(1.4) Å³. Void volume calculation using the SQUEEZE routine in PLATON (Spek, 2009 ) gives a total electron count in the voids per cell of 3 e⁻ Å⁻³ suggesting that no solvent molecules occupy these voids. The Flack parameter is −0.051 (9); however, this ambiguity is resolved as the Flack parameter of the inverted structure is calculated to 1.052 (9). This indicates that the original absolute structure has been assigned correctly.

Table 3
Experimental details

Crystal data
Chemical formula	[Ag₄(C₉H₁₀O₄)₂(C₁₈H₁₅P)₄]
M_r	1844.90
Crystal system, space group	Tetragonal, I $[\overline{4}]$
Temperature (K)	105
a, c (Å)	16.0462 (1), 15.3337 (2)
V (Å³)	3948.13 (7)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	1.12
Crystal size (mm)	0.2 × 0.1 × 0.1

Data collection
Diffractometer	Oxford Gemini S
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ )
T_min, T_max	0.903, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	21141, 4571, 4425
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.671

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.022, 0.048, 1.04
No. of reflections	4571
No. of parameters	240
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.40, −0.52
Absolute structure	Flack x determined using 1620 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons & Flack, 2004 )
Absolute structure parameter	−0.051 (9)
Computer programs: CrysAlis CCD and CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ), SHELXS2013, SHELXL2013 and SHELXTL (Sheldrick, 2008 ), ORTEP-3 for Windows and WinGX (Farrugia, 2012 ), DIAMOND (Brandenburg, 1996 ), publCIF (Westrip, 2010 ) and PLATON (Spek, 2009).

Supporting information

CCDC reference: 1021407

Crystal structure: contains datablock I. DOI: 10.1107/S1600536814019394/wm5047sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814019394/wm5047Isup2.hkl

checkCIF report

Chemical context top

Silver(I) carboxylates of general type [AgO₂CR]_n (n is the degree of aggregation) are of interest due to their versatile structures in the solid state and in solution, their synthetic methodologies and their manifold reaction behavior (see, for example: Schliebe et al., 2013; Jahn et al., 2010; Wang et al., 2008; Fernández et al., 2007; Olson et al., 2006; Szymańska et al., 2007). These metal-organic complexes are of importance not only in the field of basic research but also in multipurpose applications including, for example, metallization processes for micro- and nano-structured new materials in electronic systems and devices (e.g. using chemical vapour deposition, CVD), since silver possesses the highest electrical conductivity of any element (Jakob et al., 2010; Lang & Dietrich, 2013), catalytic processes (Steffan et al., 2009) and their use in biological studies (Djokić, 2008; Zhu et al., 2003).

Structural commentary top

The asymmetric unit of (I) contains one quarter of the molecule which is completed by application of a fourfold screw axis as the symmetry element. The resulting tetranuclear silver core is decorated by four triphenylphosphane ligands, whereby the metal ions are bridged by two 2,2-diallylmalonate anions in a µ₄-(κ⁶O¹,O³:O³:O^1',O^3':O^1') mode (Fig. 1). There is no example in the literature of a transition metal malonate displaying this type of coordination. The environment around silver, set up by one phosphorus and three oxygen atoms, is best described as distorted tetrahedral. Ag1 is oriented slightly above the plane of O1, P1 and O2ⁱⁱ [distance 0.2911 (10) Å], which is supported by the respective bond angles around Ag1 (Table 1) summing up to 354.3°. The O—Ag1—P1 angles are substantially larger than the O—Ag1—O angles, which may be attributed to the chelating coordination of the malonate ligands and the bulkiness of the triphenylphosphane ligand. The Ag—O bond lengths are more than 0.2 Å shorter for the two oxygen atoms of the aforementioned plane than for the third apical oxygen atom (Table 1). However, the values are in the expected range for Ag—O bonds in silver carboxylates.

The cyclic corner-sharing arrangement of the described O₃P tetrahedra gives the tetranuclear structure of (I) (Fig. 2). The four silver ions are oriented in a butterfly-like arrangement, which delimits the title compound from Ag₄O₄ heterocubanes (Jakob et al., 2011; Zhang et al., 2008, Kühnert et al., 2007) in which the four silver ions form a tetrahedron. In contrast, there are some similarities with [bis(1,8-naphthalenedicarboxylato)][tetrakis(triphenylphosphane)silver(I)] (van der Ploeg et al., 1979); however, in the structure of this compound one silver ion is pentacoordinated.

Supramolecular features top

Four weak intramolecular C—H···O hydrogen bonds (Steiner, 2002) are observed in the crystal structure of (I) (Table 2), which most likely stabilize the silver core.

In contrast to iridium and platinum complexes of 2,2-diallylamolic acid and derivatives thereof, the C═C double bond does not coordinate the transition metal in (I). Furthermore, no obvious π–π stacking interactions are observed between the allyl and the phenyl substituents. Therefore, the packing seems to be dominated by dispersion forces (Fig. 3).

Database survey top

2,2-Diallylmalonic acid and derivatives thereof have only been used as ligands in four mononuclear platinum and one iridium complex, in which coordination of the transition metal occurs either through (O,O')-, (O,alkene)- or (alkene,alkene')-chelation (Berthon-Gelloz et al., 2007; Makino et al., 2004; Jung et al., 1999; Lee et al., 1999). To the best of our knowledge, there are no diallylmalonate silver(I) compounds described in literature so far.

Synthesis and crystallization top

Analysis calculated for C₉₀H₈₀Ag₄O₈P₄ (1844.96): C 58.59, H 4.37. Found: C 58.53, H 4.34. ¹H NMR (500 MHz, CDCl₃, 298 K, ppm): δ = 2.79 (d, 8H, ³J_HH = 6.5 Hz, CH₂CH═CH₂), 4.97 (d, 4H, ³J_HH = 10.2 Hz, CH₂CH═CH₂), 5.03 (d, 4H, ³J_HH = 17.1 Hz, CH₂CH═CH₂), 5.90 (m, 4H, CH₂CH═ CH₂), 7.30–7.51 (m, 60H, C₆H₅). ³¹P{¹H} NMR (203 MHz, CDCl₃, 298 K, ppm): δ = 15.7 (d, ¹J_AgP = 680 Hz). IR (KBr, cm^–1): ν = 1637 (w, C═C), 1559 (vs, C═ O), 1440 (vs, P—Ph), 692 (vs), 521 (vs).

Refinement top

C-bonded H atoms were placed in calculated positions and constrained to ride on their parent atoms, with U_iso(H) = 1.2U_eq(C) and a C—H distance of 0.93 Å for aromatic and vinylic as well as 0.97 Å for methylene protons. The unit cell contains two voids of 34(1.4) Å³. Void volume calculation using the SQUEEZE routine in PLATON (Spek, 2009) gives a total electron count in the voids per cell of 3 e^- Å^-3 suggesting that no solvent molecules occupy these voids. The Flack parameter is –0.051 (9), however, this ambiguity is resolved as the Flack parameter of the inverted structure is calculated to 1.052 (9). This indicates that the original absolute structure has been assigned correctly.

Related literature top

For complexes of 2,2-diallylmalonic acid and its derivatives, see: Berthon-Gelloz et al. (2007); Makino et al. (2004); Jung et al. (1999); Lee et al. (1999). For synthetic methodologies of silver(I) carboxylates and their manifold reaction behaviour, see: Schliebe et al. (2013); Jahn et al. (2010); Wang et al. (2008); Fernández et al. (2007); Olson et al. (2006); Szymańska et al. (2007). For applications of silver(I) carboxylates, see: Jakob et al. (2010); Lang & Dietrich (2013); Steffan et al. (2009); Djokić (2008); Zhu et al. (2003). For Ag₄O₄ heterocubanes, see: Jakob et al. (2011); Zhang et al. (2008); Kühnert et al. (2007). For another tetrakis(triphenylphosphane)silver(I) complex, see: van der Ploeg et al. (1979). For weak intramolecular C—H···O hydrogen bonds, see: Steiner (2002).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis CCD (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012), SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1996); software used to prepare material for publication: WinGX (Farrugia, 2012), publCIF (Westrip, 2010) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The Ag₄O₈P₄ core of the title compound with surrounding atoms. Displacement ellipsoids are displayed at the 50% probability level. The carbon atoms of the phenyl substituents except the ipso-carbon atoms and all hydrogen atoms have been omitted for clarity. [Symmetry codes: (A) –x + 1, –y + 1, z; (B) y, –x + 1, –z + 2; (C) –y + 1, x, –z + 2.]
	Fig. 2. Structure fragment showing the cyclic corner-sharing arrangement of the AgO₃P polyhedra giving the tetranuclear silver core of composition Ag₄O₈P₄.
	Fig. 3. Packing diagram of the title compound along the c axis, voids in the structure are represented by red spheres [drawn using the CAVITYPLOT routine in PLATON (Spek, 2009)]. The hydrogen atoms have been omitted for clarity. Colour code: black (C), red (O), yellow (P), green (Ag).

cyclo-Bis(µ₄-2,2-diallylmalonato- κ⁶O¹,O³:O³:O^1',O^3':O^1')tetrakis(triphenylphosphane-κP)tetrasilver(I) top

Crystal data top

[Ag₄(C₉H₁₀O₄)₂(C₁₈H₁₅P)₄]	D_x = 1.552 Mg m⁻³
M_r = 1844.90	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4	Cell parameters from 14970 reflections
a = 16.0462 (1) Å	θ = 3.2–28.4°
c = 15.3337 (2) Å	µ = 1.12 mm⁻¹
V = 3948.13 (7) Å³	T = 105 K
Z = 2	Block, colourless
F(000) = 1864	0.2 × 0.1 × 0.1 mm

Data collection top

Oxford Gemini S diffractometer	R_int = 0.034
ω scans	θ_max = 28.5°, θ_min = 3.1°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	h = −19→20
T_min = 0.903, T_max = 1.000	k = −21→21
21141 measured reflections	l = −19→20
4571 independent reflections	2 standard reflections every 50 reflections
4425 reflections with I > 2σ(I)	intensity decay: none

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.022	w = 1/[σ²(F_o²) + (0.0226P)² + 1.5165P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.048	(Δ/σ)_max = 0.001
S = 1.04	Δρ_max = 0.40 e Å⁻³
4571 reflections	Δρ_min = −0.52 e Å⁻³
240 parameters	Absolute structure: Flack x determined using 1620 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons & Flack, 2004)
0 restraints	Absolute structure parameter: −0.051 (9)

Crystal data top

[Ag₄(C₉H₁₀O₄)₂(C₁₈H₁₅P)₄]	Z = 2
M_r = 1844.90	Mo Kα radiation
Tetragonal, I4	µ = 1.12 mm⁻¹
a = 16.0462 (1) Å	T = 105 K
c = 15.3337 (2) Å	0.2 × 0.1 × 0.1 mm
V = 3948.13 (7) Å³

Data collection top

Oxford Gemini S diffractometer	4425 reflections with I > 2σ(I)
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	R_int = 0.034
T_min = 0.903, T_max = 1.000	2 standard reflections every 50 reflections
21141 measured reflections	intensity decay: none
4571 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.022	H-atom parameters constrained
wR(F²) = 0.048	Δρ_max = 0.40 e Å⁻³
S = 1.04	Δρ_min = −0.52 e Å⁻³
4571 reflections	Absolute structure: Flack x determined using 1620 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons & Flack, 2004)
240 parameters	Absolute structure parameter: −0.051 (9)
0 restraints

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	0.42916 (19)	0.52013 (18)	1.13083 (19)	0.0162 (6)
C2	0.5000	0.5000	1.1958 (3)	0.0156 (8)
C3	0.4814 (2)	0.4235 (2)	1.2530 (2)	0.0205 (7)
H3A	0.4329	0.4350	1.2889	0.025*
H3B	0.4681	0.3765	1.2157	0.025*
C4	0.5527 (2)	0.4007 (2)	1.3107 (2)	0.0258 (7)
H4	0.6037	0.3908	1.2837	0.031*
C5	0.5502 (3)	0.3933 (3)	1.3962 (3)	0.0394 (9)
H5A	0.5005	0.4026	1.4259	0.047*
H5B	0.5980	0.3787	1.4269	0.047*
C6	0.3546 (2)	0.17708 (19)	0.9260 (2)	0.0189 (6)
C7	0.3733 (2)	0.2094 (2)	0.8438 (2)	0.0252 (7)
H7	0.4161	0.2480	0.8373	0.030*
C8	0.3276 (3)	0.1837 (2)	0.7717 (2)	0.0329 (9)
H8	0.3407	0.2047	0.7168	0.039*
C9	0.2631 (3)	0.1274 (2)	0.7803 (3)	0.0389 (10)
H9	0.2332	0.1102	0.7316	0.047*
C10	0.2434 (2)	0.0970 (2)	0.8615 (3)	0.0346 (9)
H10	0.1995	0.0597	0.8675	0.042*
C11	0.2883 (2)	0.1214 (2)	0.9348 (2)	0.0245 (7)
H11	0.2741	0.1007	0.9894	0.029*
C12	0.52112 (19)	0.17391 (19)	0.9931 (2)	0.0191 (6)
C13	0.58867 (19)	0.21305 (19)	1.0339 (2)	0.0230 (6)
H13	0.5799	0.2591	1.0696	0.028*
C14	0.6692 (2)	0.1829 (2)	1.0208 (2)	0.0295 (8)
H14	0.7140	0.2080	1.0489	0.035*
C15	0.6825 (2)	0.1156 (2)	0.9662 (3)	0.0292 (7)
H15	0.7361	0.0952	0.9580	0.035*
C16	0.6160 (2)	0.0786 (2)	0.9240 (2)	0.0267 (7)
H16	0.6252	0.0339	0.8866	0.032*
C17	0.5356 (2)	0.1078 (2)	0.9370 (2)	0.0223 (7)
H17	0.4913	0.0829	0.9079	0.027*
C18	0.38021 (19)	0.14737 (19)	1.1075 (2)	0.0184 (6)
C19	0.3973 (2)	0.0620 (2)	1.1117 (2)	0.0233 (7)
H19	0.4319	0.0376	1.0703	0.028*
C20	0.3628 (2)	0.0137 (2)	1.1771 (2)	0.0262 (7)
H20	0.3739	−0.0432	1.1794	0.031*
C21	0.3121 (2)	0.0500 (2)	1.2389 (2)	0.0258 (7)
H21	0.2889	0.0174	1.2828	0.031*
C22	0.2956 (2)	0.1343 (2)	1.2362 (2)	0.0264 (7)
H22	0.2616	0.1584	1.2784	0.032*
C23	0.3297 (2)	0.1832 (2)	1.1707 (2)	0.0207 (7)
H23	0.3187	0.2401	1.1690	0.025*
O1	0.36944 (13)	0.47026 (13)	1.12166 (14)	0.0186 (5)
O2	0.43925 (14)	0.58622 (14)	1.08654 (14)	0.0209 (5)
P1	0.41682 (5)	0.21258 (5)	1.01855 (5)	0.01656 (16)
Ag1	0.41599 (2)	0.35747 (2)	1.04012 (2)	0.01949 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0177 (16)	0.0146 (15)	0.0163 (14)	0.0002 (11)	0.0004 (12)	−0.0030 (11)
C2	0.015 (2)	0.016 (2)	0.0154 (19)	−0.0020 (16)	0.000	0.000
C3	0.0228 (17)	0.0192 (16)	0.0195 (15)	−0.0003 (12)	0.0021 (12)	−0.0004 (12)
C4	0.0282 (19)	0.0209 (17)	0.0284 (18)	0.0034 (13)	−0.0007 (14)	0.0035 (14)
C5	0.050 (3)	0.036 (2)	0.032 (2)	0.0070 (18)	−0.0071 (18)	0.0058 (17)
C6	0.0192 (16)	0.0127 (15)	0.0250 (16)	0.0044 (12)	−0.0039 (12)	−0.0018 (12)
C7	0.0280 (19)	0.0247 (18)	0.0229 (17)	0.0059 (14)	−0.0026 (13)	−0.0032 (13)
C8	0.039 (2)	0.035 (2)	0.0250 (19)	0.0123 (17)	−0.0077 (15)	−0.0018 (16)
C9	0.044 (2)	0.030 (2)	0.042 (2)	0.0116 (17)	−0.0237 (18)	−0.0141 (17)
C10	0.030 (2)	0.0236 (19)	0.050 (2)	0.0006 (15)	−0.0192 (18)	0.0006 (16)
C11	0.0211 (16)	0.0192 (16)	0.0332 (19)	0.0003 (12)	−0.0092 (13)	0.0005 (13)
C12	0.0180 (16)	0.0188 (16)	0.0204 (15)	−0.0011 (12)	−0.0030 (12)	0.0062 (12)
C13	0.0220 (16)	0.0202 (15)	0.0270 (16)	−0.0026 (11)	−0.0015 (14)	0.0025 (14)
C14	0.0206 (17)	0.0303 (19)	0.038 (2)	−0.0044 (14)	−0.0021 (15)	0.0055 (15)
C15	0.0167 (15)	0.0308 (19)	0.040 (2)	0.0026 (12)	0.0062 (16)	0.0078 (17)
C16	0.0252 (18)	0.0231 (18)	0.0318 (18)	0.0028 (14)	0.0071 (14)	0.0032 (14)
C17	0.0214 (16)	0.0205 (16)	0.0250 (18)	−0.0005 (12)	−0.0008 (12)	0.0017 (12)
C18	0.0161 (16)	0.0179 (16)	0.0211 (16)	−0.0015 (11)	−0.0029 (12)	0.0004 (12)
C19	0.0237 (18)	0.0207 (17)	0.0256 (17)	0.0010 (13)	−0.0028 (13)	0.0011 (13)
C20	0.0294 (19)	0.0185 (17)	0.0306 (19)	−0.0010 (13)	−0.0052 (14)	0.0057 (14)
C21	0.0230 (18)	0.0268 (18)	0.0274 (18)	−0.0040 (14)	−0.0028 (14)	0.0097 (14)
C22	0.0217 (19)	0.0320 (19)	0.0255 (18)	0.0024 (14)	0.0021 (14)	0.0041 (14)
C23	0.0191 (17)	0.0198 (17)	0.0234 (17)	0.0030 (12)	−0.0014 (13)	0.0026 (13)
O1	0.0154 (11)	0.0168 (11)	0.0236 (12)	−0.0017 (8)	0.0018 (9)	−0.0032 (9)
O2	0.0212 (12)	0.0188 (11)	0.0225 (12)	−0.0024 (9)	−0.0047 (9)	0.0042 (9)
P1	0.0175 (4)	0.0137 (4)	0.0185 (4)	0.0000 (3)	−0.0015 (3)	0.0002 (3)
Ag1	0.02397 (13)	0.01337 (12)	0.02114 (11)	−0.00192 (9)	0.00038 (10)	0.00018 (9)

Geometric parameters (Å, º) top

C1—O1	1.256 (3)	C13—C14	1.394 (5)
C1—O2	1.270 (4)	C13—H13	0.9300
C1—C2	1.545 (4)	C14—C15	1.383 (5)
C2—C3	1.539 (4)	C14—H14	0.9300
C2—C3ⁱ	1.539 (4)	C15—C16	1.382 (5)
C2—C1ⁱ	1.545 (4)	C15—H15	0.9300
C3—C4	1.492 (5)	C16—C17	1.386 (5)
C3—H3A	0.9700	C16—H16	0.9300
C3—H3B	0.9700	C17—H17	0.9300
C4—C5	1.318 (5)	C18—C23	1.387 (5)
C4—H4	0.9300	C18—C19	1.399 (4)
C5—H5A	0.9300	C18—P1	1.817 (3)
C5—H5B	0.9300	C19—C20	1.383 (5)
C6—C7	1.397 (5)	C19—H19	0.9300
C6—C11	1.397 (5)	C20—C21	1.378 (5)
C6—P1	1.825 (3)	C20—H20	0.9300
C7—C8	1.389 (5)	C21—C22	1.380 (5)
C7—H7	0.9300	C21—H21	0.9300
C8—C9	1.380 (6)	C22—C23	1.388 (5)
C8—H8	0.9300	C22—H22	0.9300
C9—C10	1.373 (6)	C23—H23	0.9300
C9—H9	0.9300	Ag1—O1	2.323 (2)
C10—C11	1.391 (5)	Ag1—P1	2.3483 (8)
C10—H10	0.9300	Ag1—O2ⁱ	2.592 (2)
C11—H11	0.9300	Ag1—O2ⁱⁱ	2.344 (2)
C12—C17	1.386 (5)	O2—Ag1ⁱⁱⁱ	2.344 (2)
C12—C13	1.400 (4)	O2—Ag1ⁱ	2.592 (2)
C12—P1	1.827 (3)

O1—C1—O2	124.7 (3)	C15—C14—H14	120.0
O1—C1—C2	120.0 (2)	C13—C14—H14	120.0
O2—C1—C2	115.2 (2)	C16—C15—C14	120.0 (3)
C3—C2—C3ⁱ	110.4 (4)	C16—C15—H15	120.0
C3—C2—C1ⁱ	110.11 (16)	C14—C15—H15	120.0
C3ⁱ—C2—C1ⁱ	113.04 (17)	C15—C16—C17	120.3 (3)
C3—C2—C1	113.04 (17)	C15—C16—H16	119.8
C3ⁱ—C2—C1	110.10 (16)	C17—C16—H16	119.8
C1ⁱ—C2—C1	99.8 (3)	C12—C17—C16	120.3 (3)
C4—C3—C2	112.6 (3)	C12—C17—H17	119.9
C4—C3—H3A	109.1	C16—C17—H17	119.9
C2—C3—H3A	109.1	C23—C18—C19	119.2 (3)
C4—C3—H3B	109.1	C23—C18—P1	118.3 (2)
C2—C3—H3B	109.1	C19—C18—P1	122.4 (2)
H3A—C3—H3B	107.8	C20—C19—C18	120.3 (3)
C5—C4—C3	126.0 (4)	C20—C19—H19	119.9
C5—C4—H4	117.0	C18—C19—H19	119.9
C3—C4—H4	117.0	C21—C20—C19	119.8 (3)
C4—C5—H5A	120.0	C21—C20—H20	120.1
C4—C5—H5B	120.0	C19—C20—H20	120.1
H5A—C5—H5B	120.0	C20—C21—C22	120.5 (3)
C7—C6—C11	119.2 (3)	C20—C21—H21	119.7
C7—C6—P1	118.0 (3)	C22—C21—H21	119.7
C11—C6—P1	122.8 (3)	C21—C22—C23	120.0 (3)
C8—C7—C6	119.7 (3)	C21—C22—H22	120.0
C8—C7—H7	120.2	C23—C22—H22	120.0
C6—C7—H7	120.2	C18—C23—C22	120.1 (3)
C9—C8—C7	120.9 (4)	C18—C23—H23	119.9
C9—C8—H8	119.6	C22—C23—H23	119.9
C7—C8—H8	119.6	C1—O1—Ag1	108.13 (19)
C10—C9—C8	119.5 (3)	C1—O2—Ag1ⁱⁱⁱ	111.05 (19)
C10—C9—H9	120.2	C1—O2—Ag1ⁱ	123.53 (19)
C8—C9—H9	120.2	Ag1ⁱⁱⁱ—O2—Ag1ⁱ	106.22 (8)
C9—C10—C11	120.9 (4)	C18—P1—C6	103.13 (15)
C9—C10—H10	119.6	C18—P1—C12	105.12 (14)
C11—C10—H10	119.6	C6—P1—C12	103.22 (15)
C10—C11—C6	119.8 (3)	C18—P1—Ag1	117.56 (10)
C10—C11—H11	120.1	C6—P1—Ag1	114.54 (10)
C6—C11—H11	120.1	C12—P1—Ag1	111.81 (10)
C17—C12—C13	119.4 (3)	O1—Ag1—P1	148.09 (6)
C17—C12—P1	123.1 (2)	O1—Ag1—O2ⁱ	82.45 (7)
C13—C12—P1	117.5 (2)	O1—Ag1—O2ⁱⁱ	90.28 (8)
C14—C13—C12	119.8 (3)	P1—Ag1—O2ⁱ	112.26 (5)
C14—C13—H13	120.1	O2ⁱⁱ—Ag1—P1	115.95 (6)
C12—C13—H13	120.1	O2ⁱⁱ—Ag1—O2ⁱ	92.63 (10)
C15—C14—C13	120.1 (3)

O1—C1—C2—C3	−8.4 (4)	C19—C20—C21—C22	−0.2 (5)
O2—C1—C2—C3	175.2 (3)	C20—C21—C22—C23	0.3 (5)
O1—C1—C2—C3ⁱ	−132.4 (3)	C19—C18—C23—C22	−1.0 (5)
O2—C1—C2—C3ⁱ	51.2 (4)	P1—C18—C23—C22	175.4 (3)
O1—C1—C2—C1ⁱ	108.5 (3)	C21—C22—C23—C18	0.2 (5)
O2—C1—C2—C1ⁱ	−67.9 (2)	O2—C1—O1—Ag1	100.7 (3)
C3ⁱ—C2—C3—C4	−60.5 (2)	C2—C1—O1—Ag1	−75.4 (3)
C1ⁱ—C2—C3—C4	65.0 (4)	O1—C1—O2—Ag1ⁱⁱⁱ	−17.0 (4)
C1—C2—C3—C4	175.6 (2)	C2—C1—O2—Ag1ⁱⁱⁱ	159.23 (19)
C2—C3—C4—C5	124.2 (4)	O1—C1—O2—Ag1ⁱ	−144.9 (2)
C11—C6—C7—C8	−2.2 (5)	C2—C1—O2—Ag1ⁱ	31.3 (3)
P1—C6—C7—C8	179.7 (3)	C23—C18—P1—C6	−106.6 (3)
C6—C7—C8—C9	1.0 (5)	C19—C18—P1—C6	69.7 (3)
C7—C8—C9—C10	0.5 (6)	C23—C18—P1—C12	145.6 (3)
C8—C9—C10—C11	−0.8 (6)	C19—C18—P1—C12	−38.1 (3)
C9—C10—C11—C6	−0.4 (5)	C23—C18—P1—Ag1	20.5 (3)
C7—C6—C11—C10	1.9 (5)	C19—C18—P1—Ag1	−163.2 (2)
P1—C6—C11—C10	179.9 (3)	C7—C6—P1—C18	−173.8 (2)
C17—C12—C13—C14	−3.0 (5)	C11—C6—P1—C18	8.2 (3)
P1—C12—C13—C14	176.2 (3)	C7—C6—P1—C12	−64.5 (3)
C12—C13—C14—C15	1.4 (5)	C11—C6—P1—C12	117.5 (3)
C13—C14—C15—C16	0.5 (5)	C7—C6—P1—Ag1	57.3 (3)
C14—C15—C16—C17	−1.0 (5)	C11—C6—P1—Ag1	−120.7 (2)
C13—C12—C17—C16	2.5 (5)	C17—C12—P1—C18	85.6 (3)
P1—C12—C17—C16	−176.6 (2)	C13—C12—P1—C18	−93.6 (3)
C15—C16—C17—C12	−0.6 (5)	C17—C12—P1—C6	−22.2 (3)
C23—C18—C19—C20	1.2 (5)	C13—C12—P1—C6	158.7 (2)
P1—C18—C19—C20	−175.1 (3)	C17—C12—P1—Ag1	−145.8 (2)
C18—C19—C20—C21	−0.6 (5)	C13—C12—P1—Ag1	35.1 (3)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13···O2ⁱ	0.93	2.51	3.351 (4)	150

Symmetry code: (i) −x+1, −y+1, z.

Selected bond lengths (Å) and bond angles (°) top

Ag1—O1	2.323 (2)	O1—Ag1—O2ⁱ	82.45 (7)
Ag1—P1	2.3483 (8)	O1—Ag1—O2ⁱⁱ	90.28 (8)
Ag1—O2ⁱ	2.592 (2)	P1—Ag1—O2ⁱ	112.26 (5)
Ag1—O2ⁱⁱ	2.344 (2)	P1—Ag1—O2ⁱⁱ	115.95 (6)
O1—Ag1—P1	148.09 (6)	O2ⁱ—Ag1—O2ⁱⁱ	92.63 (10)

Symmetry codes: (i) -x+1, -y+1, z; (ii) -y+1, x, -z+2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13···O2ⁱ	0.93	2.51	3.351 (4)	150

Symmetry code: (i) −x+1, −y+1, z.

Experimental details

Crystal data
Chemical formula	[Ag₄(C₉H₁₀O₄)₂(C₁₈H₁₅P)₄]
M_r	1844.90
Crystal system, space group	Tetragonal, I4
Temperature (K)	105
a, c (Å)	16.0462 (1), 15.3337 (2)
V (Å³)	3948.13 (7)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.12
Crystal size (mm)	0.2 × 0.1 × 0.1

Data collection
Diffractometer	Oxford Gemini S diffractometer
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.903, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	21141, 4571, 4425
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.671

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.022, 0.048, 1.04
No. of reflections	4571
No. of parameters	240
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.40, −0.52
Absolute structure	Flack x determined using 1620 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons & Flack, 2004)
Absolute structure parameter	−0.051 (9)

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS2013 (Sheldrick, 2008), SHELXL2013 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1996), WinGX (Farrugia, 2012), publCIF (Westrip, 2010) and PLATON (Spek, 2009).

Acknowledgements

Financial support from the Federal Cluster of Excellence EXC 1075 `MERGE Technologies for Multifunctional Lightweight Structures' is gratefully acknowledged. DS thanks the Fonds der Chemischen Industrie for a Chemiefonds fellowship.

References

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Volume 70| Part 10| October 2014| Pages 174-177

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