research communications\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 10| October 2014| Pages 174-177

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

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 AgI ion is coordinated by one P and three O atoms in a considerably distorted tetra­hedral environment. The two 2,2-di­allyl­malonate anions bridge four AgI ions in a μ4-(κ6O1,O3:O3:O1′,O3′:O1′) 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 d10d10 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.

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[Schliebe, C., Jiang, K., Schulze, S., Hietschold, M., Cai, W.-B. & Lang, H. (2013). Chem. Commun. 49, 3991-3993.]; Jahn et al., 2010[Jahn, S. F., Jakob, A., Blaudeck, T., Schmidt, P., Lang, H. & Baumann, R. R. (2010). Thin Solid Films, 518, 3218-3222.]; Wang et al., 2008[Wang, Y.-L., Liu, Q.-Y. & Xu, L. (2008). CrystEngComm, 10, 1667-1673.]; Fernández et al., 2007[Fernández, E. J., Jones, P. G., Laguna, A., López-de-Luzuriaga, J. M., Monge, M., Olmos, M. E. & Puelles, R. C. (2007). Organometallics, 26, 5931-5939.]; Olson et al., 2006[Olson, L. P., Whitcomb, D. R., Rajeswaran, M., Blanton, T. N. & Stwertka, B. J. (2006). Chem. Mater. 18, 1667-1674.]; Szymańska et al., 2007[Szymańska, I., Piszczek, P., Szczęsny, R. & Szłyk, E. (2007). Polyhedron, 26, 2440-2448.]). 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[Jakob, A., Rüffer, T., Schmidt, H., Djiele, P., Körbitz, K., Ecorchard, P., Haase, T., Kohse-Höinghaus, K., Frühauf, S., Wächtler, T., Schulz, S., Gessner, T. & Lang, H. (2010). Eur. J. Inorg. Chem. 19, 2975-2986.]; Lang & Dietrich, 2013[Lang, H. & Dietrich, S. (2013). 4.10 - Metals - Gas-Phase Deposition and Applications, in Comprehensive Inorganic Chemistry II (Second Edition), edited by J. Reedijk & K. Poeppelmeier, pp. 211-269. Amsterdam: Elsevier.]), catalytic processes (Steffan et al., 2009[Steffan, M., Jakob, A., Claus, P. & Lang, H. (2009). Catal. Commun. 10, 437-441.]) and their use in biological studies (Djokić, 2008[Djokić, S. (2008). Bioinorg. Chem. Appl. pp. 1-7.]; Zhu et al., 2003[Zhu, H.-L., Zhang, X.-M., Liu, X.-Y., Wang, X.-Y., Liu, G.-F., Usman, A. & Fun, H.-K. (2003). Inorg. Chem. Commun. 6, 1113-1116.]).

[Scheme 1]

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)[link], was obtained by the reaction of the silver salt of 2,2-di­allyl­malonic acid with tri­phenyl­phosphane.

2. Structural commentary

The asymmetric unit of (I)[link] 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:O1′,O3′:O1′) mode (Fig. 1[link]). 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[link]) 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[link]). 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]
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)[link] (Fig. 2[link]). The four silver ions are oriented in a butterfly-like arrangement, which delimits the title compound from Ag4O4 heterocubanes (Jakob et al., 2011[Jakob, A., Schmidt, H., Walfort, B., Rüffer, T., Haase, T., Kohse-Höinghaus, K. & Lang, H. (2011). Inorg. Chim. Acta, 365, 1-9.]; Zhang et al., 2008[Zhang, Y.-Y., Wang, Y., Tao, X., Wang, N. & Shen, Y.-Z. (2008). Polyhedron, 27, 2501-2505.], Kühnert et al., 2007[Kühnert, J., Lamač, M., Rüffer, T., Walfort, B., Štěpnička, P. & Lang, H. (2007). J. Organomet. Chem. 692, 4303-4314.]) 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[Ploeg, A. F. M. J. van der, van Koten, G. & Spek, A. L. (1979). Inorg. Chem. 18, 1052-1060.]); however, in the structure of this compound one silver ion is penta­coordinated.

[Figure 2]
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[Steiner, T. (2002). Angew. Chem. Int. Ed. 41, 48-76.]) are observed in the crystal structure of (I)[link] (Table 2[link]), which most likely stabilize the silver core.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA 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)[link]. Furthermore, no obvious ππ stacking inter­actions are observed between the allyl and the phenyl substituents. Therefore, the packing seems to be dominated by dispersion forces (Fig. 3[link]).

[Figure 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[Spek, A. L. (2009). Acta Cryst. D65, 148-155.])]. 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[Berthon-Gelloz, G., Schumers, J.-M., Lucaccioni, F., Tinant, B., Wouters, J. & Markó, I. E. (2007). Organometallics, 26, 5731-5737.]; Makino et al., 2004[Makino, T., Yamamoto, Y. & Itoh, K. (2004). Organometallics, 23, 1730-1737.]; Jung et al., 1999[Jung, O. S., Lee, Y.-A., Park, S. H. & Yoo, K. H. (1999). Bull. Chem. Soc. Jpn, 72, 2091-2096.]; Lee et al., 1999[Lee, Y.-A., Chung, Y. K. & Sohn, Y. S. (1999). Inorg. Chem. 38, 531-537.]). 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)[link] was obtained as a pale-grey solid. Colourless crystals of (I)[link] were obtained by solvent diffusion of a chloro­form solution of (I)[link] 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, 3JHH = 6.5 Hz, CH2CH=CH2), 4.97 (d, 4H, 3JHH = 10.2 Hz, CH2CH=CH2), 5.03 (d, 4H, 3JHH = 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, 1JAgP = 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[link]. C-bonded H atoms were placed in calculated positions and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(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[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) 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]
Mr 1844.90
Crystal system, space group Tetragonal, I[\overline{4}]
Temperature (K) 105
a, c (Å) 16.0462 (1), 15.3337 (2)
V3) 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.])
Tmin, Tmax 0.903, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 21141, 4571, 4425
Rint 0.034
(sin θ/λ)max−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
Δρmax, Δρmin (e Å−3) 0.40, −0.52
Absolute structure Flack x determined using 1620 quotients [(I+)−(I)]/[(I+)+(I)] (Parsons & Flack, 2004[Parsons, S. & Flack, H. (2004). Acta Cryst. A60, s61.])
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[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), ORTEP-3 for Windows and WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), DIAMOND (Brandenburg, 1996[Brandenburg, K. (1996). DIAMOND. University of Bonn, Germany.]), publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


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).

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.

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:O1',O3':O1') 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 CC double bond does not coordinate the transition metal in (I). Furthermore, no obvious ππ 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

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, 3JHH = 6.5 Hz, CH2CHCH2), 4.97 (d, 4H, 3JHH = 10.2 Hz, CH2CHCH2), 5.03 (d, 4H, 3JHH = 17.1 Hz, CH2CHCH2), 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, 1JAgP = 680 Hz). IR (KBr, cm–1): ν = 1637 (w, CC), 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 Uiso(H) = 1.2Ueq(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
[Figure 1] 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.]
[Figure 2] Fig. 2. Structure fragment showing the cyclic corner-sharing arrangement of the AgO3P polyhedra giving the tetranuclear silver core of composition Ag4O8P4.
[Figure 3] 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:O1',O3':O1')tetrakis(triphenylphosphane-κP)tetrasilver(I) top
Crystal data top
[Ag4(C9H10O4)2(C18H15P)4]Dx = 1.552 Mg m3
Mr = 1844.90Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4Cell parameters from 14970 reflections
a = 16.0462 (1) Åθ = 3.2–28.4°
c = 15.3337 (2) ŵ = 1.12 mm1
V = 3948.13 (7) Å3T = 105 K
Z = 2Block, colourless
F(000) = 18640.2 × 0.1 × 0.1 mm
Data collection top
Oxford Gemini S
diffractometer
Rint = 0.034
ω scansθmax = 28.5°, θmin = 3.1°
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2006)
h = 1920
Tmin = 0.903, Tmax = 1.000k = 2121
21141 measured reflectionsl = 1920
4571 independent reflections2 standard reflections every 50 reflections
4425 reflections with I > 2σ(I) intensity decay: none
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.022 w = 1/[σ2(Fo2) + (0.0226P)2 + 1.5165P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.048(Δ/σ)max = 0.001
S = 1.04Δρmax = 0.40 e Å3
4571 reflectionsΔρmin = 0.52 e Å3
240 parametersAbsolute structure: Flack x determined using 1620 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004)
0 restraintsAbsolute structure parameter: 0.051 (9)
Crystal data top
[Ag4(C9H10O4)2(C18H15P)4]Z = 2
Mr = 1844.90Mo Kα radiation
Tetragonal, I4µ = 1.12 mm1
a = 16.0462 (1) ÅT = 105 K
c = 15.3337 (2) Å0.2 × 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)
Rint = 0.034
Tmin = 0.903, Tmax = 1.0002 standard reflections every 50 reflections
21141 measured reflections intensity decay: none
4571 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.022H-atom parameters constrained
wR(F2) = 0.048Δρmax = 0.40 e Å3
S = 1.04Δρmin = 0.52 e Å3
4571 reflectionsAbsolute structure: Flack x determined using 1620 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004)
240 parametersAbsolute 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
xyzUiso*/Ueq
C10.42916 (19)0.52013 (18)1.13083 (19)0.0162 (6)
C20.50000.50001.1958 (3)0.0156 (8)
C30.4814 (2)0.4235 (2)1.2530 (2)0.0205 (7)
H3A0.43290.43501.28890.025*
H3B0.46810.37651.21570.025*
C40.5527 (2)0.4007 (2)1.3107 (2)0.0258 (7)
H40.60370.39081.28370.031*
C50.5502 (3)0.3933 (3)1.3962 (3)0.0394 (9)
H5A0.50050.40261.42590.047*
H5B0.59800.37871.42690.047*
C60.3546 (2)0.17708 (19)0.9260 (2)0.0189 (6)
C70.3733 (2)0.2094 (2)0.8438 (2)0.0252 (7)
H70.41610.24800.83730.030*
C80.3276 (3)0.1837 (2)0.7717 (2)0.0329 (9)
H80.34070.20470.71680.039*
C90.2631 (3)0.1274 (2)0.7803 (3)0.0389 (10)
H90.23320.11020.73160.047*
C100.2434 (2)0.0970 (2)0.8615 (3)0.0346 (9)
H100.19950.05970.86750.042*
C110.2883 (2)0.1214 (2)0.9348 (2)0.0245 (7)
H110.27410.10070.98940.029*
C120.52112 (19)0.17391 (19)0.9931 (2)0.0191 (6)
C130.58867 (19)0.21305 (19)1.0339 (2)0.0230 (6)
H130.57990.25911.06960.028*
C140.6692 (2)0.1829 (2)1.0208 (2)0.0295 (8)
H140.71400.20801.04890.035*
C150.6825 (2)0.1156 (2)0.9662 (3)0.0292 (7)
H150.73610.09520.95800.035*
C160.6160 (2)0.0786 (2)0.9240 (2)0.0267 (7)
H160.62520.03390.88660.032*
C170.5356 (2)0.1078 (2)0.9370 (2)0.0223 (7)
H170.49130.08290.90790.027*
C180.38021 (19)0.14737 (19)1.1075 (2)0.0184 (6)
C190.3973 (2)0.0620 (2)1.1117 (2)0.0233 (7)
H190.43190.03761.07030.028*
C200.3628 (2)0.0137 (2)1.1771 (2)0.0262 (7)
H200.37390.04321.17940.031*
C210.3121 (2)0.0500 (2)1.2389 (2)0.0258 (7)
H210.28890.01741.28280.031*
C220.2956 (2)0.1343 (2)1.2362 (2)0.0264 (7)
H220.26160.15841.27840.032*
C230.3297 (2)0.1832 (2)1.1707 (2)0.0207 (7)
H230.31870.24011.16900.025*
O10.36944 (13)0.47026 (13)1.12166 (14)0.0186 (5)
O20.43925 (14)0.58622 (14)1.08654 (14)0.0209 (5)
P10.41682 (5)0.21258 (5)1.01855 (5)0.01656 (16)
Ag10.41599 (2)0.35747 (2)1.04012 (2)0.01949 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0177 (16)0.0146 (15)0.0163 (14)0.0002 (11)0.0004 (12)0.0030 (11)
C20.015 (2)0.016 (2)0.0154 (19)0.0020 (16)0.0000.000
C30.0228 (17)0.0192 (16)0.0195 (15)0.0003 (12)0.0021 (12)0.0004 (12)
C40.0282 (19)0.0209 (17)0.0284 (18)0.0034 (13)0.0007 (14)0.0035 (14)
C50.050 (3)0.036 (2)0.032 (2)0.0070 (18)0.0071 (18)0.0058 (17)
C60.0192 (16)0.0127 (15)0.0250 (16)0.0044 (12)0.0039 (12)0.0018 (12)
C70.0280 (19)0.0247 (18)0.0229 (17)0.0059 (14)0.0026 (13)0.0032 (13)
C80.039 (2)0.035 (2)0.0250 (19)0.0123 (17)0.0077 (15)0.0018 (16)
C90.044 (2)0.030 (2)0.042 (2)0.0116 (17)0.0237 (18)0.0141 (17)
C100.030 (2)0.0236 (19)0.050 (2)0.0006 (15)0.0192 (18)0.0006 (16)
C110.0211 (16)0.0192 (16)0.0332 (19)0.0003 (12)0.0092 (13)0.0005 (13)
C120.0180 (16)0.0188 (16)0.0204 (15)0.0011 (12)0.0030 (12)0.0062 (12)
C130.0220 (16)0.0202 (15)0.0270 (16)0.0026 (11)0.0015 (14)0.0025 (14)
C140.0206 (17)0.0303 (19)0.038 (2)0.0044 (14)0.0021 (15)0.0055 (15)
C150.0167 (15)0.0308 (19)0.040 (2)0.0026 (12)0.0062 (16)0.0078 (17)
C160.0252 (18)0.0231 (18)0.0318 (18)0.0028 (14)0.0071 (14)0.0032 (14)
C170.0214 (16)0.0205 (16)0.0250 (18)0.0005 (12)0.0008 (12)0.0017 (12)
C180.0161 (16)0.0179 (16)0.0211 (16)0.0015 (11)0.0029 (12)0.0004 (12)
C190.0237 (18)0.0207 (17)0.0256 (17)0.0010 (13)0.0028 (13)0.0011 (13)
C200.0294 (19)0.0185 (17)0.0306 (19)0.0010 (13)0.0052 (14)0.0057 (14)
C210.0230 (18)0.0268 (18)0.0274 (18)0.0040 (14)0.0028 (14)0.0097 (14)
C220.0217 (19)0.0320 (19)0.0255 (18)0.0024 (14)0.0021 (14)0.0041 (14)
C230.0191 (17)0.0198 (17)0.0234 (17)0.0030 (12)0.0014 (13)0.0026 (13)
O10.0154 (11)0.0168 (11)0.0236 (12)0.0017 (8)0.0018 (9)0.0032 (9)
O20.0212 (12)0.0188 (11)0.0225 (12)0.0024 (9)0.0047 (9)0.0042 (9)
P10.0175 (4)0.0137 (4)0.0185 (4)0.0000 (3)0.0015 (3)0.0002 (3)
Ag10.02397 (13)0.01337 (12)0.02114 (11)0.00192 (9)0.00038 (10)0.00018 (9)
Geometric parameters (Å, º) top
C1—O11.256 (3)C13—C141.394 (5)
C1—O21.270 (4)C13—H130.9300
C1—C21.545 (4)C14—C151.383 (5)
C2—C31.539 (4)C14—H140.9300
C2—C3i1.539 (4)C15—C161.382 (5)
C2—C1i1.545 (4)C15—H150.9300
C3—C41.492 (5)C16—C171.386 (5)
C3—H3A0.9700C16—H160.9300
C3—H3B0.9700C17—H170.9300
C4—C51.318 (5)C18—C231.387 (5)
C4—H40.9300C18—C191.399 (4)
C5—H5A0.9300C18—P11.817 (3)
C5—H5B0.9300C19—C201.383 (5)
C6—C71.397 (5)C19—H190.9300
C6—C111.397 (5)C20—C211.378 (5)
C6—P11.825 (3)C20—H200.9300
C7—C81.389 (5)C21—C221.380 (5)
C7—H70.9300C21—H210.9300
C8—C91.380 (6)C22—C231.388 (5)
C8—H80.9300C22—H220.9300
C9—C101.373 (6)C23—H230.9300
C9—H90.9300Ag1—O12.323 (2)
C10—C111.391 (5)Ag1—P12.3483 (8)
C10—H100.9300Ag1—O2i2.592 (2)
C11—H110.9300Ag1—O2ii2.344 (2)
C12—C171.386 (5)O2—Ag1iii2.344 (2)
C12—C131.400 (4)O2—Ag1i2.592 (2)
C12—P11.827 (3)
O1—C1—O2124.7 (3)C15—C14—H14120.0
O1—C1—C2120.0 (2)C13—C14—H14120.0
O2—C1—C2115.2 (2)C16—C15—C14120.0 (3)
C3—C2—C3i110.4 (4)C16—C15—H15120.0
C3—C2—C1i110.11 (16)C14—C15—H15120.0
C3i—C2—C1i113.04 (17)C15—C16—C17120.3 (3)
C3—C2—C1113.04 (17)C15—C16—H16119.8
C3i—C2—C1110.10 (16)C17—C16—H16119.8
C1i—C2—C199.8 (3)C12—C17—C16120.3 (3)
C4—C3—C2112.6 (3)C12—C17—H17119.9
C4—C3—H3A109.1C16—C17—H17119.9
C2—C3—H3A109.1C23—C18—C19119.2 (3)
C4—C3—H3B109.1C23—C18—P1118.3 (2)
C2—C3—H3B109.1C19—C18—P1122.4 (2)
H3A—C3—H3B107.8C20—C19—C18120.3 (3)
C5—C4—C3126.0 (4)C20—C19—H19119.9
C5—C4—H4117.0C18—C19—H19119.9
C3—C4—H4117.0C21—C20—C19119.8 (3)
C4—C5—H5A120.0C21—C20—H20120.1
C4—C5—H5B120.0C19—C20—H20120.1
H5A—C5—H5B120.0C20—C21—C22120.5 (3)
C7—C6—C11119.2 (3)C20—C21—H21119.7
C7—C6—P1118.0 (3)C22—C21—H21119.7
C11—C6—P1122.8 (3)C21—C22—C23120.0 (3)
C8—C7—C6119.7 (3)C21—C22—H22120.0
C8—C7—H7120.2C23—C22—H22120.0
C6—C7—H7120.2C18—C23—C22120.1 (3)
C9—C8—C7120.9 (4)C18—C23—H23119.9
C9—C8—H8119.6C22—C23—H23119.9
C7—C8—H8119.6C1—O1—Ag1108.13 (19)
C10—C9—C8119.5 (3)C1—O2—Ag1iii111.05 (19)
C10—C9—H9120.2C1—O2—Ag1i123.53 (19)
C8—C9—H9120.2Ag1iii—O2—Ag1i106.22 (8)
C9—C10—C11120.9 (4)C18—P1—C6103.13 (15)
C9—C10—H10119.6C18—P1—C12105.12 (14)
C11—C10—H10119.6C6—P1—C12103.22 (15)
C10—C11—C6119.8 (3)C18—P1—Ag1117.56 (10)
C10—C11—H11120.1C6—P1—Ag1114.54 (10)
C6—C11—H11120.1C12—P1—Ag1111.81 (10)
C17—C12—C13119.4 (3)O1—Ag1—P1148.09 (6)
C17—C12—P1123.1 (2)O1—Ag1—O2i82.45 (7)
C13—C12—P1117.5 (2)O1—Ag1—O2ii90.28 (8)
C14—C13—C12119.8 (3)P1—Ag1—O2i112.26 (5)
C14—C13—H13120.1O2ii—Ag1—P1115.95 (6)
C12—C13—H13120.1O2ii—Ag1—O2i92.63 (10)
C15—C14—C13120.1 (3)
O1—C1—C2—C38.4 (4)C19—C20—C21—C220.2 (5)
O2—C1—C2—C3175.2 (3)C20—C21—C22—C230.3 (5)
O1—C1—C2—C3i132.4 (3)C19—C18—C23—C221.0 (5)
O2—C1—C2—C3i51.2 (4)P1—C18—C23—C22175.4 (3)
O1—C1—C2—C1i108.5 (3)C21—C22—C23—C180.2 (5)
O2—C1—C2—C1i67.9 (2)O2—C1—O1—Ag1100.7 (3)
C3i—C2—C3—C460.5 (2)C2—C1—O1—Ag175.4 (3)
C1i—C2—C3—C465.0 (4)O1—C1—O2—Ag1iii17.0 (4)
C1—C2—C3—C4175.6 (2)C2—C1—O2—Ag1iii159.23 (19)
C2—C3—C4—C5124.2 (4)O1—C1—O2—Ag1i144.9 (2)
C11—C6—C7—C82.2 (5)C2—C1—O2—Ag1i31.3 (3)
P1—C6—C7—C8179.7 (3)C23—C18—P1—C6106.6 (3)
C6—C7—C8—C91.0 (5)C19—C18—P1—C669.7 (3)
C7—C8—C9—C100.5 (6)C23—C18—P1—C12145.6 (3)
C8—C9—C10—C110.8 (6)C19—C18—P1—C1238.1 (3)
C9—C10—C11—C60.4 (5)C23—C18—P1—Ag120.5 (3)
C7—C6—C11—C101.9 (5)C19—C18—P1—Ag1163.2 (2)
P1—C6—C11—C10179.9 (3)C7—C6—P1—C18173.8 (2)
C17—C12—C13—C143.0 (5)C11—C6—P1—C188.2 (3)
P1—C12—C13—C14176.2 (3)C7—C6—P1—C1264.5 (3)
C12—C13—C14—C151.4 (5)C11—C6—P1—C12117.5 (3)
C13—C14—C15—C160.5 (5)C7—C6—P1—Ag157.3 (3)
C14—C15—C16—C171.0 (5)C11—C6—P1—Ag1120.7 (2)
C13—C12—C17—C162.5 (5)C17—C12—P1—C1885.6 (3)
P1—C12—C17—C16176.6 (2)C13—C12—P1—C1893.6 (3)
C15—C16—C17—C120.6 (5)C17—C12—P1—C622.2 (3)
C23—C18—C19—C201.2 (5)C13—C12—P1—C6158.7 (2)
P1—C18—C19—C20175.1 (3)C17—C12—P1—Ag1145.8 (2)
C18—C19—C20—C210.6 (5)C13—C12—P1—Ag135.1 (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···AD—HH···AD···AD—H···A
C13—H13···O2i0.932.513.351 (4)150
Symmetry code: (i) x+1, y+1, z.
Selected bond lengths (Å) and bond angles (°) top
Ag1—O12.323 (2)O1—Ag1—O2i82.45 (7)
Ag1—P12.3483 (8)O1—Ag1—O2ii90.28 (8)
Ag1—O2i2.592 (2)P1—Ag1—O2i112.26 (5)
Ag1—O2ii2.344 (2)P1—Ag1—O2ii115.95 (6)
O1—Ag1—P1148.09 (6)O2i—Ag1—O2ii92.63 (10)
Symmetry codes: (i) -x+1, -y+1, z; (ii) -y+1, x, -z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13···O2i0.932.513.351 (4)150
Symmetry code: (i) x+1, y+1, z.

Experimental details

Crystal data
Chemical formula[Ag4(C9H10O4)2(C18H15P)4]
Mr1844.90
Crystal system, space groupTetragonal, I4
Temperature (K)105
a, c (Å)16.0462 (1), 15.3337 (2)
V3)3948.13 (7)
Z2
Radiation typeMo Kα
µ (mm1)1.12
Crystal size (mm)0.2 × 0.1 × 0.1
Data collection
DiffractometerOxford Gemini S
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2006)
Tmin, Tmax0.903, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
21141, 4571, 4425
Rint0.034
(sin θ/λ)max1)0.671
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.022, 0.048, 1.04
No. of reflections4571
No. of parameters240
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.40, 0.52
Absolute structureFlack x determined using 1620 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack, 2004)
Absolute structure parameter0.051 (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

First citationBerthon-Gelloz, G., Schumers, J.-M., Lucaccioni, F., Tinant, B., Wouters, J. & Markó, I. E. (2007). Organometallics, 26, 5731–5737.  CAS Google Scholar
First citationBrandenburg, K. (1996). DIAMOND. University of Bonn, Germany.  Google Scholar
First citationDjokić, S. (2008). Bioinorg. Chem. Appl. pp. 1–7.  Google Scholar
First citationFarrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationFernández, E. J., Jones, P. G., Laguna, A., López-de-Luzuriaga, J. M., Monge, M., Olmos, M. E. & Puelles, R. C. (2007). Organometallics, 26, 5931–5939.  Google Scholar
First citationJahn, S. F., Jakob, A., Blaudeck, T., Schmidt, P., Lang, H. & Baumann, R. R. (2010). Thin Solid Films, 518, 3218–3222.  Web of Science CrossRef CAS Google Scholar
First citationJakob, A., Rüffer, T., Schmidt, H., Djiele, P., Körbitz, K., Ecorchard, P., Haase, T., Kohse-Höinghaus, K., Frühauf, S., Wächtler, T., Schulz, S., Gessner, T. & Lang, H. (2010). Eur. J. Inorg. Chem. 19, 2975–2986.  Web of Science CSD CrossRef Google Scholar
First citationJakob, A., Schmidt, H., Walfort, B., Rüffer, T., Haase, T., Kohse-Höinghaus, K. & Lang, H. (2011). Inorg. Chim. Acta, 365, 1–9.  Web of Science CSD CrossRef CAS Google Scholar
First citationJung, O. S., Lee, Y.-A., Park, S. H. & Yoo, K. H. (1999). Bull. Chem. Soc. Jpn, 72, 2091–2096.  Web of Science CSD CrossRef CAS Google Scholar
First citationKühnert, J., Lamač, M., Rüffer, T., Walfort, B., Štěpnička, P. & Lang, H. (2007). J. Organomet. Chem. 692, 4303–4314.  Google Scholar
First citationLang, H. & Dietrich, S. (2013). 4.10 – Metals – Gas-Phase Deposition and Applications, in Comprehensive Inorganic Chemistry II (Second Edition), edited by J. Reedijk & K. Poeppelmeier, pp. 211–269. Amsterdam: Elsevier.  Google Scholar
First citationLee, Y.-A., Chung, Y. K. & Sohn, Y. S. (1999). Inorg. Chem. 38, 531–537.  Web of Science CSD CrossRef PubMed CAS Google Scholar
First citationMakino, T., Yamamoto, Y. & Itoh, K. (2004). Organometallics, 23, 1730–1737.  Web of Science CSD CrossRef CAS Google Scholar
First citationOlson, L. P., Whitcomb, D. R., Rajeswaran, M., Blanton, T. N. & Stwertka, B. J. (2006). Chem. Mater. 18, 1667–1674.  Web of Science CrossRef CAS Google Scholar
First citationOxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.  Google Scholar
First citationParsons, S. & Flack, H. (2004). Acta Cryst. A60, s61.  CrossRef IUCr Journals Google Scholar
First citationPloeg, A. F. M. J. van der, van Koten, G. & Spek, A. L. (1979). Inorg. Chem. 18, 1052–1060.  Google Scholar
First citationSchliebe, C., Jiang, K., Schulze, S., Hietschold, M., Cai, W.-B. & Lang, H. (2013). Chem. Commun. 49, 3991–3993.  Web of Science CrossRef CAS Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSteffan, M., Jakob, A., Claus, P. & Lang, H. (2009). Catal. Commun. 10, 437–441.  Web of Science CrossRef CAS Google Scholar
First citationSteiner, T. (2002). Angew. Chem. Int. Ed. 41, 48–76.  Web of Science CrossRef CAS Google Scholar
First citationSzymańska, I., Piszczek, P., Szczęsny, R. & Szłyk, E. (2007). Polyhedron, 26, 2440–2448.  Google Scholar
First citationWang, Y.-L., Liu, Q.-Y. & Xu, L. (2008). CrystEngComm, 10, 1667–1673.  Web of Science CSD CrossRef CAS Google Scholar
First citationWestrip, S. P. (2010). J. Appl. Cryst. 43, 920–925.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationZhang, Y.-Y., Wang, Y., Tao, X., Wang, N. & Shen, Y.-Z. (2008). Polyhedron, 27, 2501–2505.  Web of Science CSD CrossRef CAS Google Scholar
First citationZhu, H.-L., Zhang, X.-M., Liu, X.-Y., Wang, X.-Y., Liu, G.-F., Usman, A. & Fun, H.-K. (2003). Inorg. Chem. Commun. 6, 1113–1116.  Web of Science CSD CrossRef CAS Google Scholar

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