The ability of an atom or molecular fragment to bind multiple carbon monoxide (CO) molecules to form multicarbonyl adducts is a fundamental trait of transition metals. Transition-metal carbonyl complexes are vital to industry, appear naturally in the active sites of a number of enzymes (such as hydrogenases), are promising therapeutic agents1, and have even been observed in interstellar dust clouds2. Despite the wealth of established transition-metal multicarbonyl complexes3, no elements outside groups 4 to 12 of the periodic table have yet been shown to react directly with two or more CO units to form stable multicarbonyl adducts. Here we present the synthesis of a borylene dicarbonyl complex, the first multicarbonyl complex of a main-group element prepared using CO. The compound is additionally stable towards ambient air and moisture. The synthetic strategy used—liberation of a borylene ligand from a transition metal using donor ligands—is broadly applicable, leading to a number of unprecedented monovalent boron species with different Lewis basic groups. The similarity of these compounds to conventional transition-metal carbonyl complexes is demonstrated by photolytic liberation of CO and subsequent intramolecular carbon–carbon bond activation.
Subscribe to Journal
Get full journal access for 1 year
only $3.90 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Simpson, P. V. & Schatzschneider, U. in Inorganic Chemical Biology: Principles, Techniques and Applications (ed. Gasser, G.) Ch.10, 309–340 (Wiley, 2014)
Tielens, A. G. G. M., Wooden, D. H., Allamandola, L. J., Bregman, J. & Witteborn, F. C. The infrared spectrum of the galactic center and the composition of interstellar dust. Astrophys. J. 461, 210–222 (1996)
The Cambridge Crystallographic Database. http://www.ccdc.cam.ac.uk/data_request/cif, Version 5.35 (Cambridge Crystallographic Data Centre, November 2013)
Parry, J., Carmona, E., Coles, S. & Hursthouse, M. Synthesis and single crystal X-ray diffraction study on the first isolable carbonyl complex of an actinide, (C5Me4H)3U(CO). J. Am. Chem. Soc. 117, 2649–2650 (1995)
Puschmann, F. F. et al. Phosphination of carbon monoxide: a simple synthesis of sodium phosphaethynolate (NaOCP). Angew. Chem. Int. Ed. 50, 8420–8423 (2011)
Finze, M. et al. Tris(trifluoromethyl)borane carbonyl, (CF3)3BCO—synthesis, physical, chemical and spectroscopic properties, gas phase, and solid state structure. J. Am. Chem. Soc. 124, 15385–15398 (2002)
Glore, J. D., Rathke, J. W. & Schaeffer, R. Some reactions of triborane(7) and the structure of triborane(7)-carbonyl. Inorg. Chem. 12, 2175–2178 (1973)
Lavallo, V., Canac, Y., Donnadieu, B., Schoeller, W. W. & Bertrand, G. CO fixation to stable acyclic and cyclic alkyl amino carbenes: stable amino ketenes with a small HOMO–LUMO gap. Angew. Chem. Int. Ed. 45, 3488–3491 (2006)
Ellern, A., Drews, T. & Seppelt, K. The structure of carbon suboxide, C3O2, in the solid state. Z. Anorg. Allg. Chem. 627, 73–76 (2001)
Bernhardi, I., Drews, T. & Seppelt, K. Isolation and structure of the OCNCO+ ion. Angew. Chem. Int. Ed. 38, 2232–2233 (1999)
Power, P. P. Main-group elements as transition metals. Nature 463, 171–177 (2010)
Martin, D., Soleilhavoup, M. & Bertrand, G. Stable singlet carbenes as mimics for transition metal centers. Chem. Sci. 2, 389–399 (2011)
Braunschweig, H. et al. Ambient-temperature isolation of a compound with a boron-boron triple bond. Science 336, 1420–1422 (2012)
Wang, Y. & Robinson, G. H. Carbene-stabilized main group diatomic allotropes. Dalton Trans. 41, 337–345 (2012)
Khan, S., Sen, S. S. & Roesky, H. W. Activation of phosphorus by group 14 elements in low oxidation states. Chem. Commun. 48, 2169–2179 (2012)
Braunschweig, H. et al. Metal-free binding and coupling of carbon monoxide at a boron–boron triple bond. Nature Chem. 5, 1025–1028 (2013)
Spikes, G. H., Fettinger, J. C. & Power, P. P. Facile activation of dihydrogen by an unsaturated heavier main group compound. J. Am. Chem. Soc. 127, 12232–12233 (2005)
Frey, G. D., Lavallo, V., Donnadieu, B., Schoeller, W. W. & Bertrand, G. Facile splitting of hydrogen and ammonia by nucleophilic activation at a single carbon center. Science 316, 439–441 (2007)
Tonner, R. & Frenking, G. C(NHC)2: divalent carbon(0) compounds with N-heterocyclic carbene ligands—theoretical evidence for a class of molecules with promising chemical properties. Angew. Chem. Int. Ed. 46, 8695–8698 (2007)
Celik, M. A. et al. Borylene complexes (BH)L2 and nitrogen cation complexes (N+)L2: isoelectronic homologues of carbones CL2 . Chemistry 18, 5676–5692 (2012)
Kinjo, R., Donnadieu, B., Celik, M. A., Frenking, G. & Bertrand, G. Synthesis and characterization of a neutral tricoordinate organoboron isoelectronic with amines. Science 333, 610–613 (2011)
Ruiz, D. A., Melaimi, M. & Bertrand, G. An efficient synthetic route to stable bis(carbene)borylenes [(L1)(L2)BH]. Chem. Commun. 50, 7837–7839 (2014)
Kong, L., Li, Y., Ganguly, R., Vidovic, D. & Kinjo, R. Isolation of a bis(oxazol-2-ylidene)–phenylborylene adduct and its reactivity as a boron-centered nucleophile. Angew. Chem. Int. Ed. 53, 9280–9283 (2014)
Dahcheh, F., Martin, D., Stephan, D. W. & Bertrand, G. Synthesis and reactivity of a CAAC–aminoborylene adduct: a hetero-allene or an organoboron isoelectronic with singlet carbenes. Angew. Chem. Int. Ed. 53, 13159–13163 (2014)
Mondal, K. C. et al. A stable singlet biradicaloid siladicarbene: (L:)2Si. Angew. Chem. Int. Ed. 52, 2963–2967 (2013)
Himmel, D., Krossing, I. & Schnepf, A. Dative bonds in main-group compounds: a case for fewer arrows!. Angew. Chem. Int. Ed. 53, 370–374 (2014)
Frenking, G. Dative bonds in main-group compounds: a case for more arrows!. Angew. Chem. Int. Ed. 53, 6040–6046 (2014)
Himmel, D., Krossing, I. & Schnepf, A. Dative or not dative? Angew. Chem. Int. Ed. 53, 6047–6048 (2014)
Braunschweig, H., Dewhurst, R. D. & Schneider, A. Electron-precise coordination modes of boron-centered ligands. Chem. Rev. 110, 3924–3957 (2010)
Grigsby, W. J. & Power, P. P. Isolation and reduction of sterically encumbered arylboron dihalides: novel boranediyl insertion into C−C σ-bonds. J. Am. Chem. Soc. 118, 7981–7988 (1996)
This work was supported by a European Research Council Advanced Grant to H.B.
The authors declare no competing financial interests.
Crystallographic data have been deposited with the Cambridge Crystallographic Data Center as supplementary publication numbers CCDC 1049463–1049468. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre at http://www.ccdc.cam.ac.uk/data_request/cif.
About this article
Cite this article
Braunschweig, H., Dewhurst, R., Hupp, F. et al. Multiple complexation of CO and related ligands to a main-group element. Nature 522, 327–330 (2015). https://doi.org/10.1038/nature14489
Dalton Transactions (2021)
The Journal of Physical Chemistry Letters (2021)
Angewandte Chemie International Edition (2021)
Dalton Transactions (2021)
Angewandte Chemie (2021)