Transition metal ether complex

Structure of the ether complex HfCl4(thf)2fwn

In chemistry, a transition metal ether complex is a coordination complex consisting of a transition metal bonded to one or more ether ligand. The inventory of complexes is extensive. Common ether ligands are diethyl ether and tetrahydrofuran. Common chelating ether ligands include the glymes, dimethoxyethane (dme) and diglyme, and the crown ethers. Being lipophilic, metal-ether complexes often exhibit solubility in organic solvents, a property of interest in synthetic chemistry. In contrast, the diether 1,4-dioxane is generally a bridging ligand.

Bonding, structure, reactions

In almost all of its complexes, dioxane is a bridging, not chelating, ligand. Structure of the coordination polymer of cobalt(II) chloride and 1,4-dioxane.

Ethers are L-type ligands. They are σ-donors that exert weak field ligands. They resemble water ligands as seen in aquo complexes. They do not, however, readily participate in hydrogen bonding. The ether oxygen is nearly trigonal planar in its complexes.

Being weakly basic, ether ligands tend to be easily displaceable. Otherwise, ether ligands are relatively unreactive. Cyclic ethers such as thf can ring-open or even deoxygenated when bound to highly electrophilic metal halides. Thus treatment of tungsten hexachloride with one equivalent of thf gives 1,4-dichlorobutane:

WCl6 + OC4H8 → WOCl4 + ClCH2CH2CH2CH2Cl

At higher concentrations of thf, polytetrahydrofuran is produced.

Examples

Homoleptic complexes

Ethers are relatively bulky ligands, thus homoleptic (all ligands being the same) ether complexes are uncommon. Examples often feature weakly coordinating anions such as B(ArF)−4 and Al(ORF)−4.

Metal halide complexes

Structure of NiI2(dme)2 as determined by X-ray crystallography. The sum of the angles at O is 352°, indicating a nearly planar ether oxygen. Color code: O = red, I = purple, Ni = blue, C = black.
Structure of FeCl3(diethylether)2. Color code: Cl=green, Fe = blue, O = red.

Metal chloride-tetrahydrofuran complexes are especially studied. These compounds are reagents because they are "organic-soluble" source of anhydrous halides. The following trends are observed: for diethyl ether forms isolable complexes with only highly electrophilic halides, thf forms more extensive set of complexes with a more extensive set of metal chlorides. Heavier, late metal halides (RuCl3 to CdCl2 and OsCl4 to HgCl2) do not form isolable complexes with simple ethers.

Formula of
M–Cl–ether complexes		Coordination
sphere		color and comment
ScCl3(thf)3mer-ScO3Cl3colorless
TiCl4(Et2O)2cis-TiO2Cl4yellow
TiCl4(thf)2cis and trans-TiO2Cl4yellow Both cis and trans isomers have been reported
TiCl3(thf)3mer-TiO3Cl3 blue
[TiCl3(thf)2]2TiO2Cl4green
ZrCl4(Et2O)2trans-ZrO2Cl4white
ZrCl4(thf)2cis-ZrO2Cl4white
HfCl4(thf)2cis-HfO2Cl4white
VCl3(thf)3mer-VO3Cl3 pink
[VCl3(thf)2]2trans-VO2Cl4red
NbCl4(Et2O)2trans-NbO2Cl4yellow
NbCl4(thf)2trans-NbO2Cl4yellow
Ta3Cl9(thf)4TaO2Cl4 and TaOCl5green
CrCl3(thf)3mer-CrO3Cl3pink
MoCl4(thf)2trans-MoO2Cl4pink
MoCl4(Et2O)2trans-MoO2Cl4beige
MoCl3(thf)3mer-MoO3Cl3red
WCl3(thf)3mer-WO3Cl3yellow
WCl4(Et2O)2trans-WO2Cl4yellow
MnCl3(thf)3mer-MnO3Cl3brown-purple
TcCl4(thf)2cis-TcO2Cl4yellow
ReCl4(thf)2cis-ReO2Cl4green See also: ReCl4(dme)
Fe4Cl8(thf)6FeO2Cl3, FeO2Cl4brown
FeCl3(thf)2FeO2Cl3the related diethyl ether complex is brown
FeCl3(OEt2)2FeO2Cl3brown
Co4Cl8(thf)6CoO2Cl3, CoO2Cl4blue isostructural with Fe analogue
[CoCl2(dme)]2CoO2Cl3pink
NiCl2(dimethoxyethane)2cis-NiCl2O4yellow
[Cu2Cl4(thf)3]nCuO2Cl4, CuOCl4orange
ZnCl2(thf)2ZnO2Cl2white

Metal carbonyl complexes

Ethers are widely used as ligands beyond transition metal chemistry. Few alkali metal halides form isolable adducts, but the divalent alkaline earth complexes are well known, such as BeCl2(OEt2)2.

References

  1. ↑ Duraj, S. A.; Towns; Baker; Schupp, J. (1990). "Structure of cis-Tetrachlorobis(tetrahydrofuran)hafnium(IV)". Acta Crystallographica C. 46 (5): 890–892. Bibcode:1990AcCrC..46..890D. doi:10.1107/S010827018901382X.
  2. ↑ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8.
  3. ↑ Duan, Zhiming; Zhang, Yan; Zhang, Bin; Zhu, Daoben (2009). "Crystal-to-Crystal Transformation from Antiferromagnetic Chains into a Ferromagnetic Diamondoid Framework". Journal of the American Chemical Society. 131 (20): 6934–6935. Bibcode:2009JAChS.131.6934D. doi:10.1021/ja902101x. PMID 19402661.
  4. 1 2 Schubert, U.; Friedrich, P.; Orama, O. (1978). "Kristall- und Molekülstruktur von Pentacarbonyltetrahydrofuran-Chrom(0)". Journal of Organometallic Chemistry. 144 (2): 175–179. doi:10.1016/S0022-328X(00)84160-1.
  5. ↑ Bianchi, Sabrina; Bortoluzzi, Marco; Castelvetro, Valter; Marchetti, Fabio; Pampaloni, Guido; Pinzino, Calogero; Zacchini, Stefano (2016). "The reactivity of tungsten hexachloride with tetrahydrofuran and 2-methoxyethanol". Polyhedron. 117: 769–776. doi:10.1016/j.poly.2016.07.024. hdl:11568/803763.
  6. ↑ Choukroun, Robert; Moumboko, Pierre; Chevalier, Sandrine; Etienne, Michel; Donnadieu, Bruno (1998). "Cationic Homoleptic Vanadium(II), (IV), and (V) Complexes Arising from Protonolysis of [V(NEt2)4]". Angewandte Chemie International Edition. 37 (22): 3169–3172. doi:10.1002/(SICI)1521-3773(19981204)37:22<3169::AID-ANIE3169>3.0.CO;2-0. PMID 29711321.
  7. ↑ Kong, Gapgoung; Harakas, George N.; Whittlesey, Bruce R. (1995). "An Unusual Transition Metal Cluster Containing a Seven Metal Atom Plane. Syntheses and Crystal Structures of [Mn][Mn7(THF)6(CO)12]2, Mn3(THF)2(CO)10, and [Mn(THF)6][Mn(CO)5]2". Journal of the American Chemical Society. 117 (12): 3502–3509. Bibcode:1995JAChS.117.3502K. doi:10.1021/ja00117a019.
  8. ↑ Lichtenberg, Crispin; Adelhardt, Mario; Wörle, Michael; Büttner, Torsten; Meyer, Karsten; Grützmacher, Hansjörg (2015). "Mono- and Dinuclear Neutral and Cationic Iron(II) Compounds Supported by an Amidinato-diolefin Ligand: Characterization and Catalytic Application". Organometallics. 34 (12): 3079–3089. doi:10.1021/acs.organomet.5b00395.
  9. ↑ Schwab, Miriam M.; Himmel, Daniel; Kacprzak, Sylwia; Radtke, Valentin; Kratzert, Daniel; Yassine, Zeinab; Weis, Philippe; Weber, Stefan; Krossing, Ingo (2018). "Reactivity of [Ni(cod)2][Al(ORF)4] towards Small Molecules and Elements". Zeitschrift für Anorganische und Allgemeine Chemie. 644 (1): 50–57. Bibcode:2018ZAACh.644...50S. doi:10.1002/zaac.201700367.
  10. ↑ Crochet, Aurélien; Fromm, Katharina M. (2010). "Polyether Adducts of d-Block Metal Compounds as Starting Materials for New Cluster Compounds" (PDF). Zeitschrift für anorganische und allgemeine Chemie. 636 (8): 1484–1496. Bibcode:2010ZAACh.636.1484C. doi:10.1002/zaac.201000022.
  11. 1 2 Spandl, Johann; Kusserow, M.; Brüdgam, I. (2003). "Alkoxo-Verbindungen des dreiwertigen Eisen: Synthese und Charakterisierung von [Fe2(OtBu)6], [Fe2Cl2(OtBu)4], [Fe2Cl4(OtBu)2] und [N(nBu)4]2[Fe6OCl6(OMe)12]". Zeitschrift für anorganische und allgemeine Chemie. 629 (6): 968–974. Bibcode:2003ZAACh.629..968S. doi:10.1002/zaac.200300008.
  12. 1 2 3 4 5 6 Manzer, L. E. (1982). "Tetrahydrofuran Complexes of Selected Early Transition Metals". Inorganic Syntheses. 21: 135–140. doi:10.1002/9780470132524.ch31.
  13. ↑ Atwood, J. L.; Smith, K. D. (1974). "Crystal and Molecular Structure of Trichlorotris(tetrahydrofuran)scandium(III)". Journal of the Chemical Society, Dalton Transactions (9): 921. doi:10.1039/dt9740000921.
  14. ↑ S. I. Troyanov, G. N. Mazo, V.B. Rybakov, K.V.Budkina (1990). "title unknown". Koord. Khim. 16: 466.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  15. ↑ T. Lis, J. Ejfler, J. Utko, P. Sobota (1992). "unknown". Pol. J. Chem. 66: 93. {{cite journal}}: Cite uses generic title (help)CS1 maint: multiple names: authors list (link)
  16. ↑ C. Krempner, H. Reinke. K. Weichert (2007). "Synthesis and structure of titanium and zirconium disilane-1,2-diolates". Polyhedron. 31 (14): 3633–3637. doi:10.1016/j.poly.2007.03.043.
  17. ↑ Handlovič, M.; Mikloš, D.; Zikmund, M. (1981). "The Structure of Trichlorotris(tetrahydrofuran)titanium(III)". Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry. 37 (4): 811–814. Bibcode:1981AcCrB..37..811H. doi:10.1107/S056774088100438X.
  18. 1 2 Sobota, Piotr; Ejfler, Jolanta; Szafert, Sławomir; Szczegot, Krzysztof; Sawka-Dobrowolska, Wanda (1993). "New intermediates for the Synthesis of Olefin Polymerization Catalysts: The Complexes [M2(μ-Cl)2Cl4(THF)4] (M = Ti or V, THF = Tetrahydrofuran); Crystal Structures and Properties". Journal of the Chemical Society, Dalton Transactions (15): 2353–2357. doi:10.1039/dt9930002353.
  19. ↑ E.V.Avtomonov, K.A.Rufanov (1999). "title unknown". Z. Naturforsch. B. 54: 1563. doi:10.1515/znb-1999-1214.
  20. 1 2 Albert Cotton, F.; Duraj, Stan A.; Powell, Gregory L.; Roth, Wieslaw J. (1986). "Comparative structural studies of the first row early transition metal(III) chloride tetrahydrofuran solvates". Inorganica Chimica Acta. 113: 81–85. doi:10.1016/S0020-1693(00)86863-2.
  21. ↑ Shaw, Thomas E.; Stern, Charlotte L.; Sattelberger, Alfred P.; Jurca, Titel (2023). "Facile Access to Mid-Valent Group 5 and 6 Metal Synthons". Inorganic Chemistry Frontiers. 10 (19): 5584–5590. doi:10.1039/D3QI00910F.
  22. 1 2 Babaian-Kibala, Elizabeth; Cotton, F. Albert; Shang, Maoyu (1990). "New Synthetic Routes for the Preparation of Niobium(III) and Tantalum(III) Triangular Cluster Compounds". Inorganic Chemistry. 29 (26): 5148–5156. doi:10.1021/ic00351a005.
  23. 1 2 Boudjouk, Philip; So, Jeung-Ho (1992). "Solvated and Unsolvated Anhydrous Metal Chlorides from Metal Chloride Hydrates". Inorganic Syntheses. Vol. 29. pp. 108–111. doi:10.1002/9780470132609.ch26. ISBN 9780470132609.
  24. 1 2 Dilworth, Jonathan R.; Richards, Raymond L. (1990). "The Synthesis of Molybdenum and Tungsten Dinitrogen Complexes". Inorganic Syntheses. Vol. 28. pp. 33–43. doi:10.1002/9780470132593.ch7. ISBN 9780470132593.
  25. ↑ Maria, Sébastien; Poli, Rinaldo (2014). "Ether Complexes of Molybdenum(III) and Molybdenum(IV) chlorides" (PDF). Inorganic Syntheses. Vol. 36. pp. 15–18. doi:10.1002/9781118744994.ch03. ISBN 9781118744994.
  26. ↑ P.Hofacker, C.Friebel, K.Dehnicke, P.Bauml, W.Hiller, J.Strahle (1989). "Über die Reduktion von Alkinkomplexen des Molybdäns und Wolframs in hohen Oxidationsstufen. Die Kristallstruktur von MoCl3(THF)3 / On the Reduction of Alkyne Complexes of Molybdenum and Tungsten in High Oxidation States. The Crystal Structure of MoCl3(THF)3". Z. Naturforsch. B. 44 (10): 1161. doi:10.1515/znb-1989-1002.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  27. ↑ Kim, Esther; Odom, Aaron L.; Cummins, Christopher C. (1998). "Synthesis of mer-trichlorotris(tetrahydrofuran) tungsten(III) by intermetal chlorine atom transfer". Inorganica Chimica Acta. 278: 103–107. doi:10.1016/S0020-1693(97)06157-4.
  28. ↑ Kim, Esther; Odom, Aaron L.; Cummins, Christopher C. (1998). "Synthesis of mer-Trichlorotris(tetrahydrofuran) Tungsten(III) by Intermetal Chlorine Atom Transfer". Inorganica Chimica Acta. 278: 103–107. doi:10.1016/S0020-1693(97)06157-4.
  29. ↑ Schäfer, André (2021). "The Decades-Old Mystery of Bis(diethyl ether)tungsten(IV) Chloride Solved". Acta Crystallographica Section C Structural Chemistry. 77 (4): 167–168. Bibcode:2021AcCrC..77..167S. doi:10.1107/S2053229621002461. PMC 8020884. PMID 33818437.
  30. ↑ Shaw, Thomas E.; Diethrich, Timothy J.; Stern, Charlotte L.; Scott, Brian L.; Jurca, Titel; Gilbert, Thomas M.; Sattelberger, Alfred P. (2022). "Synthesis, characterization, X-ray and electronic structures of diethyl ether and 1,2-dimethoxyethane adducts of molybdenum(iv) chloride and tungsten(iv) chloride". Dalton Transactions. 51 (20): 7856–7863. doi:10.1039/D2DT00787H. PMID 35531983.
  31. ↑ Nachtigall, Olaf; Pataki, Astrid; Molski, Matthias; Lentz, Dieter; Spandl, Johann (2015). "Solvates of Manganese Trichloride Revisited - Synthesis, Isolation, and Crystal Structure of MnCl3(THF)3". Zeitschrift für Anorganische und Allgemeine Chemie. 641 (6): 1164–1168. Bibcode:2015ZAACh.641.1164N. doi:10.1002/zaac.201500106.
  32. ↑ Hagenbach, Adelheid; Yegen, Eda; Abram, Ulrich (2006). "Technetium Tetrachloride as a Precursor for Small Technetium(IV) Complexes". Inorganic Chemistry. 45 (18): 7331–7338. doi:10.1021/ic060896u. PMID 16933935.
  33. ↑ Swidersky, H.-W.; Pebler, J.; Dehnicke, K.; Fenske, D. (1990). "Technetium Tetrachloride as a Precursor for Small Technetium(IV) Complexes". Inorganic Chemistry. 45 (18): 7331–8. doi:10.1021/ic060896u. PMID 16933935.
  34. ↑ von Gudenberg, Dorothea Wolff; Sens, Irina; Müller, Ulrich; Neumüller, Bernhard; Dehnicke, Kurt (1992). "Chelatkomplexe von Rheniumtetrachlorid. Die Kristallstrukturen von ReCl4(DME) und ReCl4(DPPE) · Tolan". Zeitschrift für Anorganische und Allgemeine Chemie. 613 (7): 49–54. doi:10.1002/zaac.19926130108.
  35. ↑ Cotton, F. Albert; Luck, Rudy L.; Son, Kyung-Ae (1991). "New polynuclear compounds of iron(II) chloride with oxygen donor ligands Part I. Fe4Cl8(THF)6: Synthesis and a single crystal X-ray structure determination". Inorganica Chimica Acta. 179: 11–15. doi:10.1016/S0020-1693(00)85366-9.
  36. ↑ L. V. Ivakina, N. R. Strel'tsova, V. K. Bel'skii, P. A. Storozhenko, B. M. Bulychev, A. B. Tarasov (1987). Zh. Obshch. Khim. (Russ. J. Gen. Chem.). 57: 1600. {{cite journal}}: Missing or empty |title= (help)CS1 maint: multiple names: authors list (link)
  37. ↑ Sobota, Piotr; Olejnik, Zofia; Utko, Józef; Lis, Tadeusz (1993). "Synthesis, Magnetic Properties and Structure of the [Co4(μ3-Cl)2(μ2-Cl)4Cl2(THF)6] Complex". Polyhedron. 12 (6): 613–616. doi:10.1016/S0277-5387(00)84976-1.
  38. ↑ Petriček, Saša (2011). "Octahedral and Tetrahedral Cobalt(II) Sites in Cobalt Chloride Complexes with Polyethers". Croatica Chemica Acta: 515–520. doi:10.5562/cca1747.
  39. ↑ Ward, Laird G. L. (1972). "Anhydrous Nickel(II) Halides and their Tetrakis(ethanol) and 1,2-Dimethoxyethane Complexes". Inorganic Syntheses. Vol. 13. pp. 154–164. doi:10.1002/9780470132449.ch30. ISBN 9780470132449.
  40. ↑ Becker, Sabine; Dürr, Maximilian; Miska, Andreas; Becker, Jonathan; Gawlig, Christopher; Behrens, Ulrich; Ivanović-Burmazović, Ivana; Schindler, Siegfried (2016). "Copper Chloride Catalysis: Do μ4-Oxido Copper Clusters Play a Significant Role?". Inorganic Chemistry. 55 (8): 3759–3766. doi:10.1021/acs.inorgchem.5b02576. PMID 27045752.
  41. ↑ Ruhlandt-Senge, Karin; Bartlett, Ruth A.; Olmstead, Marilyn M.; Power, Philip P. (1993). "Synthesis and structural characterization of the beryllium compounds [Be(2,4,6-Me3C6H2)2(OEt2)], [Be{O(2,4,6-tert-Bu3C6H2)}2(OEt2)], and [Be{S(2,4,6-tert-Bu3C6H2)}2(THF)]·PhMe and determination of the structure of [BeCl2(OEt2)2]". Inorganic Chemistry. 32 (9): 1724–1728. doi:10.1021/ic00061a031.