PROCEEDINGS OF THE SHEVCHENKO SCIENTIFIC SOCIETY

Chemical Sciences

Archive / Том LVI 2019

Nikolai KOROTKIKH1, Gennady RAYENKO2, Vagiz SABEROV1, Оles SHVAIKA2

1Institute of Organic Chemistry of UNAS, Murmanskaya, 5, 02094 Kyiv, Ukraine
2L.M. Litvinenko Institute of Physical Organic and Coal Chemistry of UNAS, Kharkiv road, 50, 02160 Kyiv, Ukraine

DOI: https://doi.org/10.37827/ntsh.chem.2019.56.007

DIMERIZATION ENERGIES AS AN IMPORTANT FACTOR OF CARBENE STABILITY. I. IMIDAZOL-2-YLIDENES.

A review of the dimerization reactions of carbenes and methods for their studies is given. The basic types of heterocyclic carbene dimers, which have been isolated and described up today, the types of carbenes that do not undergo dimerization, dimeric biscarbenes, cyclophanic dimers and polycarbenes, are presented. The mechanism of dimers formation on the example of interaction of carbenes of different nature is determined including the cases of recyclization reactions of cyclopropenylidene derivatives. It was described the approaches to the determination of the dimerization energy via the singlet-triplet splitting energies (the approach of Carter and Goddard, Kassaee), via the enthalpies of isodesmic reactions with methane and the linear equations between the electron and steric parameters of substituents for relatively simple carbenes (Nyulaszi). The energy of dimerization (electronic and steric parameter ESP) is first used in the work to assess the stability of the complicated substituted carbenic system of imidazol-2-ylidenes. The quantum-chemical calculation results of the dimerization energies of known and new promising carbenes of a series of imidazol-2-ylidenes are estimated in this work using the DFT method (B3LYP5, 3-21G та 6-31G, RHF). The scale of influence of substituents on the stability of carbenes in a series of imidazol-2-ylidenes has been developed. For 1-tert-butyl substituted compounds, the following range of substituents is observed for the ESP: Dbp > Dipp > Mes > CPh3 > PAd2 ≈ t-C4F9 > PtBu2 > 1-Ad ≈t-Bu> NMe2> Np> NiРr2 > i–Pr > Me. For 1-benzhydryl substituted substituted the series is as follows: Dbp > Dipp > t-Bu > Mes > Me > i-Pr. For 1-methyl substituted compounds the next row is given: СPh3 > Dipp > 1-Ad > PAd2 > РtBu2 > t-Bu > Np > Dbp > Mes > NiРr2 > NMe2 > Ph > i-Pr > Me > P(i-Pr2N)2). Based on the values of the dimerization energies, conclusions are made regarding the effect of the heterocyclic nucleus on the stability of carbenes. Imidazol-2-ylidenes are among the most stable according to this property. It is shown that the steric influence of the substituents affects not only the kinetic, but also the thermodynamic stabilization of the carbenes.

Keywords: dimerization energies, heterocyclic carbenes, effect of structure.

References:

  1. Kirmse W. Chemistry of carbenes. Мoscow: Mir. 1966. 324 p.
  2. Nefedov О.М., Ioffe А.I., Menchikov L.G. Chemistry of carbenes. Мoscow: Khimiya. 1990. 303 p.
  3. Herrmann W.A., Kocher K. N-Heterocyclic carbenes. Angew. Chem. Int. Ed. 1997. Vol. 36. Р. 2162–2187 (https://doi.org/10.1002/anie.199721621).
  4. Bourissou D., Guerret O., Gabbai F. P., Bertrand G. Stable carbenes. Chem. Rev. 2000. Vol. 100. P. 39–92 (https://doi.org/10.1021/cr940472u).
  5. Vignolle J., Cattoen X., Bourissou D. Stable Noncyclic Singlet Carbenes. Chem. Rev. 2009. Vol. 109. P. 3333–3384 (https://doi.org/10.1021/cr800549j).
  6. Melaimi M., Soleilhavoup M., Bertrand G. Stable cyclic carbenes and related species beyond diaminocarbenes. Angew. Chem. Int. Ed. 2010. Vol. 49. P. 8810–8849 (http://doi.org/10.1002/anie.201000165).
  7. Martin D., Melaimi M., Soleilhavoup M., Bertrand G. A brief survey of our contribution to stable carbene chemistry. Organometallics. 2011. Vol. 30. P. 5304–5313 (http://doi.org/10.1021/om200650x).
  8. Jahnke M. C., Hahn F. E. RSC Catalysis, Ser. 6: N-Heterocyclic carbenes: from laboratory curiosities to efficient synthetic tools, Dıez-Gonzalez, S. Ed.; RSC. 2011; Chapter 1. P. 1–41 (http://doi.org/10.1039/9781782626817).
  9. Carbene chemistry. From fleeting intermediates to powerful reagent, Bertrand G. Ed.; Fontis Media. 2002. 303 p. (https://doi.org/10.1021/ja0252882).
  10. Kirmse W. The Beginnings of N-Heterocyclic Carbenes. Angew. Chem. Int. Ed. 2010. Vol. 49. P. 8798–8801 (http://doi.org/10.1002/anie.201001658).
  11. Hopkinson M. N., Richter C., Schedler M., Glorius F. An overview of N-heterocyclic carbenes. Nature. 2014. Vol. 510. P. 485–496 (http://doi.org/10.1038/nature13384).
  12. Kühl O. Functionalised N-heterocyclic carbene complexes. John Wiley & Sons Ltd. 2010. 353 p.
  13. Korotkikh N., Shvaika O. Organic reactions catalysis by carbenes and metal carbene complexes. LAP Lambert Academic Publishing. 2015. 385 p.
  14. Korotkikh N. І., Cowley А. H., Clyburne J. A.C., Robertson K. N., Saberov V. Sh., Glinyanaya N. V., Rayenko G. F., Shvaika О. P. Synthesis and properties of heteroaromatic carbenes of the imidazole and triazole series and their fused analogues. Arkivoc. 2017. Vol. 1, P. 257–355 (https://doi.org/10.24820/ark.5550190.p010.110).
  15. Shvaika О.P., Korotkikh N.I., Aslanov А.F. Heteroaromatic carbenes. Chem. Heter. Compd. 1992. Vol. 9. P. 1155 – 1170 (in Russian) (https://doi.org/10.1007/BF00531470).
  16. Wanzlick H.-W. Aspects of Nucleophilic Carbene Chemistry. Angew. Chem. Int. Ed. 1962. Vol. 1. P. 75–80 (https://doi.org/10.1002/anie.196200751).
  17. Wanzlick H.-W., Schikora E. Ein neuer Zugang zur Carben-Chemie. Angew. Chem. 1960. Vol. 72. P. 494–500 (https://doi.org/10.1002/ange.19600721409).
  18. Igau A., Grutzmacher H., Baceiredo A., Bertrand G. Analogous α,α′-Bis-Carbenoid Triply Bonded Species: Synthesis of a Stable λ3-P hosphinocarbene-λ5-Phosphaacetylene. J. Amer. Chem. Soc. 1988. Vol. 110. P. 6463–6466 (http://doi.org/10.1021/ja00227a028).
  19. Igau A., Baceiredo A., Trinquier G., Bertrand G. [Bis(diisopropylamino)phosphino]trimethylsilylcarbene: A Stable Nucleophilic Carbene. Angew. Chem. Int. Ed. 1989. Vol. 28. P. 621–622 (http://doi.org/10.1002/anie.198906211).
  20. Gillette G.R., Baceiredo A., Bertrand G. Spontaneous formation of stable phosphino-(silyl)carbenes from unstable diazocompounds. Angew. Chem. 1990. Vol. 102. P. 1486–1488 ( https://doi.org/10.1002/anie.199014291).
  21. Arduengo A.J., Harlow R.L., Kline M. A stable crystalline carbene. J. Amer. Chem. Soc. 1991. Vol. 113. P. 361–363 (http://doi.org/10.1021/ja00001a054).
  22. Arduengo A.J., Dias H.V.R., Harlow R.L., Kline M. Electronic stabilization of nucleophilic carbenes. J. Amer. Chem. Soc. 1992. Vol. 114. P. 5530–5534 (http://doi.org/10.1021/ja00040a007).
  23. Hahn F. E., Jahnke M. C. Heterocyclic Carbenes: Synthesis and Coordination Chemistry. Angew. Chem. Int. Ed. 2008. Vol. 47. P. 3122 – 3172 (http://doi.org/10.1002/anie.200703883).
  24. Wanzlick H. W., Kleiner H. J. Energiearme Carbene. Angew. Chem. 1963. Vol. 75. P. 1204 (https://doi.org/10.1002/ange.19630752406).
  25. Wiberg N. Tetraaminoethylenes as Strong Electron Donors. Angew. Chem. Int. Ed. 1968. Vol. 7. P. 766–779 (https://doi.org/10.1002/anie.196807661).
  26. Denk M. K., Hatano K., Ma M. Nucleophilic carbenes and the Wanzlick equilibrium: a reinvestigation. Tetrahedron Lett. 1999. Vol. 40. P. 2057–2060 (https://doi.org/10.1016/S0040-4039(99)00164-1).
  27. Liu Y., Lindner P. E., Lemal D. M. Thermodynamics of a Diaminocarbene-Tetra-aminoethylene Equilibrium. J. Am. Chem. Soc. 1999. Vol. 121. P. 10626–10627 (https://doi.org/10.1021/ja9922678).
  28. Arduengo A. J., III, Goerlich J. R., Marshall W. J. A stable thiazol-2-ylidene and its dimer. Lieb. Ann. Chem. Rec. 1997. P. 365–374 (https://doi.org/10.1002/jlac.199719970213).
  29. Alder R. W., Blake M. E., Oliva J.M. Diaminocarbenes; Calculation of Barriers to Rotation about Ccarbene-N Bonds, Barriers to Dimerization, Proton Affinities, and 13C NMR Shifts. J. Phys. Chem. A. 1999. Vol. 103. P. 11200–11211 (https://doi.org/10.1021/jp9934228).
  30. Alder R. W., Chaker L., Paolini F. P. V. Bis(diethylamino)carbene and the mechanism of dimerisation for simple diaminocarbenes. Chem. Commun. 2004. P. 2172–2173 (http://doi.org/10.1039/B409112D).
  31. Ma Y., Wei S., Lan J., Wang J., Xie R., You J. Pyrido[1,2-a][1,2,4]triazol-3-ylidenes as a New Family of Stable Annulated N-Heterocyclic Carbenes: Synthesis, Reactivity, and Their Application in Coordination Chemistry and Organocatalysis. J. Org. Chem. 2008. Vol. 73. P. 8256–8264 (http://doi.org/10.1021/jo801349d).
  32. Hahn F.E., Wittenbecher L., Van D.L., Frolich R. Evidence for an equilibrium between an N-heterocyclic carbene and its dimer in solution. Angew. Chem. Int. Ed. 2000. Vol. 39. P. 541–544 (https://doi.org/10.1002/(SICI)1521-3773(20000204)39:3<541::AID-ANIE541>3.0.CO;2-B).
  33. Taton T. A., Chen P. A stable tetraazafulvalene. Angew. Chem. Int. Ed. 1996. Vol. 35. P. 1011–1013 (https://doi.org/10.1002/anie.199610111).
  34. Jolly P. I., Zhou S., Thomson D. W., Garnier J., Parkinson J. A., Tuttle T., Murphy J. A. Imidazole-derived carbenes and their elusive tetraazafulvalene dimers. Chem. Sci. 2012. Vol. 3. P. 1675–1679 (http://doi.org/10.1039/C2SC20054F).
  35. Cetinkaya E., Hitchcock P. B., Kucuukbay H., Lappert M. F., Al-Juaid S. Carbene complexes. XXIV. Preparation and characterization of two enetetramine-derived carbenerhodium(I) chloride complexes RhCl(LR)3 and [RhCl(COD)LR] (LR = dCN(Me)(CH)4Me-o) and the preparation and X-ray structures of the enetetramine L2R and its salt [L2R][BF4]. J. Organomet. Chem. 1994. Vol. 481. P. 89–95 (https://doi.org/10.1016/0022-328X(94)85013-5).
  36. Shi Z., Thummel R. P. Bridged Dibenzimidazolinylidenes as New Derivatives of Tetra-aminoethylene. Tetrahedron Lett. 1995. Vol. 36. P. 2741–2744 (https://doi.org/10.1016/0040-4039(95)00386-Q).
  37. Shi Z., Thummel R. P. N,N'-Bridged Derivatives of 2,2'-Bibenzimidazole. J. Org. Chem. 1995. Vol. 60. P. 5935–5945 (https://doi.org/10.1021/jo00123a034).
  38. Shi Z., Thummel R. P. An aza-analogue of TTF: 1,1′;3,3′-bistrimethylene-2,2′-diimidazoli-nylidene. Tetrahedron Lett. 1996. Vol. 37. P. 2357–2360 (https://doi.org/10.1016/0040-4039(96)00290-0).
  39. Kamplane J.W., Bielawski C. Dynamic covalent polymers based upon carbene dimerization. Chem. Commun. 2006. P. 1727–1729 (https://doi.org/10.1039/b518246h).
  40. Kamplane J.W., Lynch V.M., Bielawski C. Synthesis and Study of Differentially Substituted Dibenzotetraazafulvalenes. Org. Lett. 2007. Vol. 9. P. 5401–5404 (https://doi.org/10.1021/ol702230r).
  41. Weinstein C. M., Martin C. D., Liu L., Bertrand G. Cross-Coupling Reactions between Stable Carbenes. Angew. Chem. Int. Ed. 2014. Vol. 53. P. 6550–6553 (https://doi.org/10.1002/anie.201404199).
  42. Carter E.A., Goddard W.A. Relation between Singlet-Triplet Gaps and Bond Energies. J. Phys. Chem. 1986. Vol. 90. P. 998–1001 (https://doi.org/10.1021/j100278a006).
  43. Malrieu J. P., Trinquier G. Trans-bending at double bonds. Occurrence and extent. J. Am. Chem. Soc. 1989. Vol. 111. P. 5916–5921 (https://doi.org/10.1021/ja00197a061).
  44. Rezaee N., Ahmadi A., Kassae M. Z. Nucleophilicity of normal and abnormal N-heterocyclic carbenes at DFT: steric effects on tetrazole-5-ylidenes RSC Adv. 2016. Vol. 6. P. 13224–13233 (https://doi.org/10.1039/C5RA21247B).
  45. Nyulaszi L., Veszpremi T., Forro A. Stabilized carbenes do not dimerize. Phys. Chem. Chem. Phys. 2000. Vol. 2. P. 3127–3129 (https://doi.org/10.1039/B003588M).
  46. Olah J., Veszpremi T. Relationship between stability and dimerization ability of silylenes. J. Organomet. Chem. 2003. Vol. 686. P. 112–117 (https://doi.org/10.1016/S0022-328X(03)00534-5).
  47. Poater A., Ragone F., Giudice S., Costabile C., Dorta R., Nolan S. P., Cavallo L. Thermodynamics of N-Heterocyclic Carbene Dimerization: The Balance of Sterics and Electronics. Organometallics. 2008. Vol. 27. P. 2679–2681 (https://doi.org/10.1021/om8001119).
  48. Hammond G. A correlation of reaction rates. J. Am. Chem. Soc. 1955. Vol. 77. P. 334–338 (https://doi.org/10.1021/ja01607a027).
  49. Gordon А., Ford R. The chemist’s companion, New-York: Wiley. 1972. 541 p (in Russian).
  50. Clavier H., Nolan S. P. Percent buried volume for phosphine and N-heterocyclic carbene ligands: steric properties in organometallic chemistry. Chem. Commun. 2010. Vol. 46. P. 841–861 (https://doi.org/10.1039/B922984A).
  51. Nelson D. J., Nolan S. P. Quantifying and understanding the electronic properties of N-heterocyclic carbenes. Chem. Soc. Rev. 2013. Vol. 42. P. 6723–6753 (https://doi.org/10.1039/C3CS60146C).
  52. Tolman C. A. Steric Effects of Phosphorus Ligands in Organometallic Chemistry and Homogeneous Catalysis. Chem. Rev. 1977. Vol. 77. P. 313–348 (https://doi.org/10.1021/cr60307a002).
  53. Korotkikh N. І., Saberov V. Sh., Rayenko G. F., Shvaika О. P. Proton affinity of heterocyclic carbenes. Scientific notes of V. Gnatyuk Ternopil national pedagogic university. 2016. Vol. 23. P. 3–11 (in Ukrainian) (http://catalog.library.tnpu.edu.ua/naukovi_zapusku/himiya/2016_23.pdf).
  54. Korotkikh N.І., Rayenko G.F., Saberov V.Sh., Popov А.F., Shavaka О.P. Proton affinity of a series of heterocyclic carbenes and their ionic forms. Ukrainian chemical journal. 2018. Vol. 84(11). P. 31–43 (in Ukrainian) (https://ucj.org.ua/index.php/journal/issue/view/10/1-2018).

How to Cite

Korotkikh N., Rayenko G., Saberov V., Shvaika О. DIMERIZATION ENERGIES AS AN IMPORTANT FACTOR OF CARBENE STABILITY. I. IMIDAZOL-2-YLIDENES. Proc. Shevchenko Sci. Soc. Chem. Sci. 2019 Vol. LVI. P. 7-22.

Download the pdf