07.01.2016
РОССИЙСКАЯ АКАДЕМИЯ НАУК

УРАЛЬСКОЕ ОТДЕЛЕНИЕ

ИНСТИТУТ ХИМИИ TBEPДОГО ТЕЛА
   
| | | | |
| | | | | |
 07.01.2016   Карта сайта     Language По-русски По-английски
Новые материалы
Экология
Электротехника и обработка материалов
Медицина
Статистика публикаций


07.01.2016

 




Four-electron deoxygenative reductive coupling of carbon monoxide at a single metal site





Journal name:

Nature

Volume:

529,

Pages:

72–75

Date published:


DOI:

doi:10.1038/nature16154



Received


Accepted


Published online









Carbon dioxide is the ultimate source of the fossil fuels that are both central to modern life and problematic: their use increases atmospheric levels of greenhouse gases, and their availability is geopolitically constrained1. Using carbon dioxide as a feedstock to produce synthetic fuels might, in principle, alleviate these concerns. Although many homogeneous and heterogeneous catalysts convert carbon dioxide to carbon monoxide2, further deoxygenative coupling of carbon monoxide to generate useful multicarbon products is challenging3. Molybdenum and vanadium nitrogenases are capable of converting carbon monoxide into hydrocarbons under mild conditions, using discrete electron and proton sources4. Electrocatalytic reduction of carbon monoxide on copper catalysts5 also uses a combination of electrons and protons, while the industrial Fischer–Tropsch process uses dihydrogen as a combined source of electrons and electrophiles for carbon monoxide coupling at high temperatures and pressures6. However, these enzymatic and heterogeneous systems are difficult to probe mechanistically. Molecular catalysts have been studied extensively6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 to investigate the elementary steps by which carbon monoxide is deoxygenated and coupled, but a single metal site that can efficiently induce the required scission of carbon–oxygen bonds and generate carbon–carbon bonds has not yet been documented. Here we describe a molybdenum compound, supported by a terphenyl–diphosphine ligand, that activates and cleaves the strong carbon–oxygen bond of carbon monoxide, enacts carbon–carbon coupling, and spontaneously dissociates the resulting fragment. This complex four-electron transformation is enabled by the terphenyl–diphosphine ligand24, 25, which acts as an electron reservoir and exhibits the coordinative flexibility needed to stabilize the different intermediates involved in the overall reaction sequence. We anticipate that these design elements might help in the development of efficient catalysts for converting carbon monoxide to chemical fuels, and should prove useful in the broader context of performing complex multi-electron transformations at a single metal site.





At a glance




Figures







left


  1. Deoxygenative coupling of CO to produce a C2O1 fragment.
    Figure 1: Deoxygenative coupling of CO to produce a C2O1 fragment.

    The overall reaction (shown at the top) involves the transformation of two Mo-bound carbonyls, with the addition of four reducing equivalents (e) and four equivalents of electrophile (E+), to generate a metal-free C2O1 product. A detailed scheme follows. Starting with compound 1, successive electron loading (to 2, then 3, then 4)—using KC8 and facilitated by electron storage in the pendant arene—leads to substantial CO activation. The addition of the silyl electrophile Me3SiCl to 3 results in C–O cleavage and the formation of silylcarbyne 7, proposed to proceed via a terminal molybdenum carbide, 8. From 7, two electrons are required for the formation of C2 products (6b and 6c), which are spontaneously displaced by N2, providing compound 5. Addition of bulkier silyl electrophiles (i-Pr3SiCl) to 3 or the more-reduced 4 results directly in the generation of compound 5 and a C2 organic fragment (6a). Synthesis of these C2O1 products (6a, 6b and 6c) from two CO ligands represents an overall four-electron transformation. E+, electrophile; e, electron; Mo, molybdenum; OTf, trifluoromethanesulfonate.




  2. X-ray crystal structures of compounds 2, 3, 4 and 7.
    Figure 2: X-ray crystal structures of compounds 2, 3, 4 and 7.

    Structures displaying a full molybdenum terphenyl–diphosphine unit are shown at the top; truncated enlargements of the molybdenum–arene cores of complexes 2 and 3 are shown in the inset. Reduction of compound 2 to generate 3 and 4 leads to deplanarization of the arene, consistent with a partial cyclohexyldienyldianion character. In the more-oxidized compound 7, no metal–arene interaction is observed. The molecular structures are displayed with anisotropic displacement ellipsoids shown at the 50% probability level. Co-crystallized solvent molecules, potassium-bound tetrahydrofuran molecules, and hydrogen atoms are omitted for clarity. A single molybdenum core is represented for the polynuclear clusters 3 and 4.




  3. NMR spectroscopic data.
    Figure 3: NMR spectroscopic data.

    These 13C{1H} NMR spectroscopic data (126 MHz, 25 °C) are for a solution of compound 8, bearing 13C-labels on the CO-derived carbon atoms, dissolved in tetrahydrofuran/benzene-d6. The coupling pattern (2J(C, C) = 3.46 Hz; 2J(P, C) = 3.26 Hz; 2J(P, CO) = 12.55 Hz) and the chemical shifts of the isotopically enriched carbon atoms are consistent with the coordination of carbide (546.20 p.p.m.) and CO ligands (233.16 p.p.m.) to the same metal centre.






right










References




  1. Appel, A. M. et al. Frontiers, opportunities, and challenges in biochemical and chemical catalysis of CO2 fixation. Chem. Rev. 113, 66216658 (2013)


  2. Costentin, C., Robert, M. & Saveant, J.-M. Catalysis of the electrochemical reduction of carbon dioxide. Chem. Soc. Rev. 42, 24232436 (2013)


  3. Gattrell, M., Gupta, N. & Co, A. A review of the aqueous electrochemical reduction of CO2 to hydrocarbons at copper. J. Electroanal. Chem. 594, 119 (2006)


  4. Hu, Y. L., Lee, C. C. & Ribbe, M. W. Extending the carbon chain: hydrocarbon formation catalyzed by vanadium/molybdenum nitrogenases. Science 333, 753755 (2011)


  5. Li, C. W., Ciston, J. & Kanan, M. W. Electroreduction of carbon monoxide to liquid fuel on oxide-derived nanocrystalline copper. Nature 508, 504507 (2014)


  6. West, N. M., Miller, A. J. M., Labinger, J. A. & Bercaw, J. E. Homogeneous syngas conversion. Coord. Chem. Rev. 255, 881898 (2011)


  7. Gardner, B. M. et al. Homologation and functionalization of carbon monoxide by a recyclable uranium complex. Proc. Natl Acad. Sci. USA 109, 92659270 (2012)


  8. Summerscales, O. T., Cloke, F. G. N., Hitchcock, P. B., Green, J. C. & Hazari, N. Reductive cyclotrimerization of carbon monoxide to the deltate dianion by an organometallic uranium complex. Science 311, 829831 (2006)


  9. Miller, R. L., Wolczanski, P. T. & Rheingold, A. L. Carbide formation via carbon monoxide dissociation across a tungsten-tungsten triple bond. J. Am. Chem. Soc. 115, 1042210423 (1993)


  10. LaPointe, R. E., Wolczanski, P. T. & Mitchell, J. F. Carbon monoxide cleavage by (silox)3Ta (silox = tert-Bu3SiO-). J. Am. Chem. Soc. 108, 63826384 (1986)


  11. Evans, W. J., Grate, J. W., Hughes, L. A., Zhang, H. & Atwood, J. L. Reductive homologation of carbon monoxide to a ketenecarboxylate by a low-valent organolanthanide complex: synthesis and x-ray crystal structure of [(C5Me5)4Sm2(O2CCCO)(THF)]2. J. Am. Chem. Soc. 107, 37283730 (1985)


  12. Ballmann, J., Pick, F., Castro, L., Fryzuk, M. D. & Maron, L. Cleavage of carbon monoxide promoted by a dinuclear tantalum tetrahydride complex. Organometallics 31, 85168524 (2012)


  13. Watanabe, T., Ishida, Y., Matsuo, T. & Kawaguchi, H. Reductive coupling of six carbon monoxides by a ditantalum hydride complex. J. Am. Chem. Soc. 131, 34743475 (2009)


  14. Shima, T. & Hou, Z. Hydrogenation of carbon monoxide by tetranuclear rare earth metal polyhydrido complexes. Selective formation of ethylene and isolation of well-defined polyoxo rare earth metal clusters. J. Am. Chem. Soc. 128, 81248125 (2006)


  15. Matsuo, T. & Kawaguchi, H. A synthetic cycle for H2/CO activation and allene synthesis using recyclable zirconium complexes. J. Am. Chem. Soc. 127, 1719817199 (2005)


  16. Belmonte, P. A., Cloke, F. G. N. & Schrock, R. R. Reduction of carbon monoxide by binuclear tantalum hydride complexes. J. Am. Chem. Soc. 105, 26432650 (1983)


  17. Carnahan, E. M., Protasiewicz, J. D. & Lippard, S. J. 15 years of reductive coupling—what have we learned? Acc. Chem. Res. 26, 9097 (1993)


  18. Büchner, W. & Weiss, E. Zur kenntnis sogenannten alkalicarbonyle 4 uber reaktion von geschmolzenem kalium mit kohlenmonoxid. Helv. Chim. Acta 47, 14151423 (1964)


  19. Wayland, B. B., Sherry, A. E. & Coffin, V. L. Selective reductive coupling of carbon-monoxide. J. Chem. Soc. Chem. Commun. 662663 (1989)

  20. Suess, D. L. M. & Peters, J. C. A CO-derived iron dicarbyne that releases olefin upon hydrogenation. J. Am. Chem. Soc. 135, 1258012583 (2013)


  21. Peters, J. C., Odom, A. L. & Cummins, C. C. A terminal molybdenum carbide prepared by methylidyne deprotonation. Chem. Commun. 19951996 (1997)

  22. Kreissl, F. R., Frank, A., Schubert, U., Lindner, T. L. & Huttner, G. Carbonyl-η-cyclopentadienyl-(4-methylphenylketenyl)-bis(trimethylphosphane)tungsten—a novel, stable transition metal-substituted ketene. Angew. Chem. Int. Edn 15, 632633 (1976)


  23. Churchill, M. R., Wasserman, H. J., Holmes, S. J. & Schrock, R. R. Coupling of methylidyne and carbonyl ligands on tungsten. Crystal structure of W(η2-HC≡COAlCl3)(CO)(PMe3)3Cl. Organometallics 1, 766768 (1982)


  24. Buss, J. A., Edouard, G. A., Cheng, C., Shi, J. & Agapie, T. Molybdenum catalyzed ammonia borane dehydrogenation: oxidation state specific mechanisms. J. Am. Chem. Soc. 136, 1127211275 (2014)


  25. Horak, K. T., Velian, A., Day, M. W. & Agapie, T. Arene non-innocence in dinuclear complexes of Fe, Co, and Ni supported by a para-terphenyl diphosphine. Chem. Commun. 50, 44274429 (2014)


  26. Cassani, M. C., Gun’ko, Y. K., Hitchcock, P. B., Lappert, M. F. & Laschi, F. Synthesis and characterization of organolanthanidocene(III) (Ln = La, Ce, Pr, Nd) complexes containing the 1,4-cyclohexa-2,5-dienyl ligand (benzene 1,4-dianion): structures of [K([18]-crown-6)][Ln{η5-C5H3(SiMe3)2-1,3}2(C6H6)] [Cp′′ = η5-C5H3(SiMe3)2-1,3; Ln = La, Ce, Nd]. Organometallics 18, 55395547 (1999)


  27. Ellis, J. E. Adventures with substances containing metals in negative oxidation states. Inorg. Chem. 45, 31673186 (2006)


  28. Enriquez, A. E., White, P. S. & Templeton, J. L. Reactions of an amphoteric terminal tungsten methylidyne complex. J. Am. Chem. Soc. 123, 49925002 (2001)


  29. Carlson, R. G. et al. The metathesis-facilitated synthesis of terminal ruthenium carbide complexes: a unique carbon atom transfer reaction. J. Am. Chem. Soc. 124, 15801581 (2002)


  30. Stewart, M. H., Johnson, M. J. A. & Kampf, J. W. Terminal carbido complexes of osmium: synthesis, structure, and reactivity comparison to the ruthenium analogues. Organometallics 26, 51025110 (2007)






 


Дизайн и программирование N-Studio 
А Б В Г Д Е Ё Ж З И Й К Л М Н О П Р С Т У Ф Х Ц Ч Ш Щ Ъ Ы Ь Э Ю Я
  • Chen Wev   honorary member of ISSC science council

  • Harton Vladislav Vadim  honorary member of ISSC science council

  • Lichtenstain Alexandr Iosif  honorary member of ISSC science council

  • Novikov Dimirtii Leonid  honorary member of ISSC science council

  • Yakushev Mikhail Vasilii  honorary member of ISSC science council

  • © 2004-2024 ИХТТ УрО РАН
    беременность, мода, красота, здоровье, диеты, женский журнал, здоровье детей, здоровье ребенка, красота и здоровье, жизнь и здоровье, секреты красоты, воспитание ребенка рождение ребенка,пол ребенка,воспитание ребенка,ребенок дошкольного возраста, дети дошкольного возраста,грудной ребенок,обучение ребенка,родить ребенка,загадки для детей,здоровье ребенка,зачатие ребенка,второй ребенок,определение пола ребенка,будущий ребенок медицина, клиники и больницы, болезни, врач, лечение, доктор, наркология, спид, вич, алкоголизм православные знакомства, православный сайт творчeства, православные рассказы, плохие мысли, православные психологи рождение ребенка,пол ребенка,воспитание ребенка,ребенок дошкольного возраста, дети дошкольного возраста,грудной ребенок,обучение ребенка,родить ребенка,загадки для детей,здоровье ребенка,зачатие ребенка,второй ребенок,определение пола ребенка,будущий ребенок