Subscribe to RSS
Please copy the URL and add it into your RSS Feed Reader.
https://www.thieme-connect.de/rss/thieme/en/10.1055-s-00000083.xml
Synlett 2019; 30(15): 1765-1775
DOI: 10.1055/s-0037-1611887
DOI: 10.1055/s-0037-1611887
account
Stable Carbon-Centered Radicals Based on N-Heterocyclic Carbenes
Funding from the Deutsche Forschungsgemeinschaft (GH 129/4) is gratefully acknowledged.Further Information
Publication History
Received: 25 May 2019
Accepted after revision: 23 June 2019
Publication Date:
12 July 2019 (online)
Abstract
Carbon-centered radicals and diradicaloids based on classical N-heterocyclic carbene (NHC) scaffolds are readily accessible as crystalline solids. The presence of an aryl (Ar) substituent at the C2-position is the key to the remarkable stability of these open-shell species as it provides appropriate room for the spin-density delocalization. Two catalytic as well as high-yielding protocols have been developed to install a suitable aryl group at the C2-position of NHCs. The spin-density in mono-radicals (NHCAr)• is mostly located on the parent carbene carbon (C2) atom. The bridging of two NHCs through a phenylene spacer (C6H4) n enables the isolation of various p-quinodimethane (p-QDM) derivatives, which may be considered as open-shell Kekulé diradicaloids. The diradical character of these NHC-analogues of Thiele (n = 1), Chichibabin (n = 2), and Müller (n = 3) hydrocarbons [(NHC)(C6H4) n (NHC)] can be tuned by a rational choice of the size and/or the topology of spacers. In this account, the synthesis, structure, and properties of this new class of radical hydrocarbons is presented.
1 Introduction
2 NHC-Monoradicals
3 NHC-Diradicaloids
4 Conclusion
-
References
- 1 Renaud P, Sibi MP. Radicals in Organic Synthesis . Wiley-VCH; Weinheim: 2008
- 2a Halliwell B, Gutteridge JM. C. Free Radicals in Biology and Medicine, 5th ed. Oxford University Press; UK: 2015
- 2b Chatgilialoglu C, Studer A. Encyclopedia of Radicals in Chemistry, Biology and Materials. Wiley-VCH; Weinheim: 2012
- 2c Berliner LJ. Spin Labeling: A Modern Perspective . In Stable Radicals . John Wiley & Sons; Hoboken: 2010. 521–534
- 2d Goldstein S, Samuni A. Biologically Relevant Chemistry of Nitroxides . In Stable Radicals . John Wiley & Sons; Hoboken: 2010. 567–576
- 3a Bielawski CW, Grubbs RH. Prog. Polym. Sci. 2007; 32: 1–29
- 3b Tomlinson EP, Hay ME, Boudouris BW. Macromolecules 2014; 47: 6145
- 4 Newcomb M. Radicals . In Reactive Intermediate Chemistry . Moss RA, Platz MS, Jones MJr. John Wiley & Sons; Hoboken: 2005. 121–163
- 5 The term ‘stable’ refers to a molecular entity that persists for many days in solution and can be isolated (or stored) at room temperature (25 °C) under an inert gas (nitrogen or argon) atmosphere without appreciable decomposition.
- 6a Hicks RG. Can. J. Chem. 2004; 82: 1119
- 6b Hicks RG. Stable Radicals: Fundamentals and Applied Aspects of Odd-Electron Compounds. John Wiley & Sons Ltd; Weinheim: 2010
- 6c Sloan GJ, Vaughan WR. J. Org. Chem. 1957; 22: 750
- 7a Ai X, Chen Y, Feng Y, Li F. Angew. Chem. Int. Ed. 2018; 57: 2869
- 7b Wilcox DA, Agarkar V, Mukherjee S, Boudouris BW. Annu. Rev. Chem. Biomol. Eng. 2018; 9: 83
- 7c Wang Y, Frasconi M, Stoddart JF. ACS Cent. Sci. 2017; 3: 927
- 8a Salem L, Rowland C. Angew. Chem. Int. Ed. Engl. 1972; 11: 92
- 8b Borden WT. Diradicals – A Fifty Year Fascination. In The Foundations of Physical Organic Chemistry: Fifty Years of the James Flack Norris Award, Vol. 1209. American Chemical Society; Washington, DC: 2015. p 251–303
- 8c Abe M. Chem. Rev. 2013; 113: 7011
- 9a Zeng Z, Shi X, Chi C, Lopez Navarrete JT, Casado J, Wu J. Chem. Soc. Rev. 2015; 44: 6578
- 9b Ratera I, Veciana J. Chem. Soc. Rev. 2012; 41: 303
- 9c Hu X, Wang W, Wang D, Zheng Y. J. Mater. Chem. C 2018; 6: 11232
- 10a Suga T, Nishide H. Rechargeable Batteries Using Robust but Redox Active Organic Radicals. In Stable Radicals. John Wiley & Sons, Ltd; Weinheim: 2010. 507–518
- 10b Luo J, Hu B, Debruler C, Liu TL. Angew. Chem. Int. Ed. 2018; 57: 231
- 10c Kim DJ, Hermann KR, Prokofjevs A, Otley MT, Pezzato C, Owczarek M, Stoddart JF. J. Am. Chem. Soc. 2017; 139: 6635
- 11 Muench S, Wild A, Friebe C, Häupler B, Janoschka T, Schubert US. Chem. Rev. 2016; 116: 9438
- 12a Beeson TD, Mastracchio A, Hong J.-B, Ashton K, MacMillan DW. C. Science 2007; 316: 582
- 12b Studer A, Curran DP. Angew. Chem. Int. Ed. 2016; 55: 58
- 13 Gomberg M. J. Am. Chem. Soc. 1900; 22: 757
- 14a Alcon I, Bromley ST. RSC Adv. 2015; 5: 98593
- 14b Tidwell TT. Triarylmethyl and Related Radicals . In Stable Radicals . John Wiley & Sons, Ltd; Weinheim: 2010. 1–3
- 14c Veciana J, Ratera I. Polychlorotriphenylmethyl Radicals: Towards Multifunctional Molecular Materials. In Stable Radicals. John Wiley & Sons, Ltd; Weinheim: 2010. 33–76
- 15a Jung Y, Head-Gordon M. ChemPhysChem 2003; 4: 522
- 15b Seierstad M, Kinsinger CR, Cramer CJ. Angew. Chem. Int. Ed. 2002; 41: 3894
- 15c Abe M, Ye J, Mishima M. Chem. Soc. Rev. 2012; 41: 3808
- 15d Grützmacher H, Breher F. Angew. Chem. Int. Ed. 2002; 41: 4006
- 15e Breher F. Coord. Chem. Rev. 2007; 251: 1007
- 16 Thiele J, Balhorn H. Ber. Dtsch. Chem. Ges. 1904; 37: 1463
- 17 Tschitschibabin AE. Ber. Dtsch. Chem. Ges. 1907; 40: 1810
- 18a Kanzaki Y, Shiomi D, Sato K, Takui T. J. Phys. Chem. B 2012; 116: 1053
- 18b McConnell HM. J. Chem. Phys. 1960; 33: 1868
- 19 Montgomery LK, Huffman JC, Jurczak EA, Grendze MP. J. Am. Chem. Soc. 1986; 108: 6004
- 20a Solà M.; Front. Chem.; 2013, 1; DOI: 10.3389/fchem.2013.00022 .
- 20b Clar E. The Aromatic Sextet . In Mobile Source Emissions Including Policyclic Organic Species . Rondia D, Cooke M, Haroz RK. Springer Netherlands; Dordrecht: 1983. 49–58
- 21 Müller E, Pfanz H. Ber. Dtsch. Chem. Ges. B 1941; 74: 1051
- 22a Kamada K, Ohta K, Kubo T, Shimizu A, Morita Y, Nakasuji K, Kishi R, Ohta S, Furukawa S.-i, Takahashi H, Nakano M. Angew. Chem. Int. Ed. 2007; 46: 3544
- 22b Sun Z, Ye Q, Chi C, Wu J. Chem. Soc. Rev. 2012; 41: 7857
- 22c Morita Y, Suzuki S, Sato K, Takui T. Nat. Chem. 2011; 3: 197
- 22d Nakano M, Champagne B. J. Phys. Chem. Lett. 2015; 6: 3236
- 23 Tan G, Wang X. Acc. Chem. Res. 2017; 50: 1997
- 24a Li G, Phan H, Herng TS, Gopalakrishna TY, Liu C, Zeng W, Ding J, Wu J. Angew. Chem. Int. Ed. 2017; 56: 5012
- 24b Liu J, Ma J, Zhang K, Ravat P, Machata P, Avdoshenko S, Hennersdorf F, Komber H, Pisula W, Weigand JJ, Popov AA, Berger R, Müllen K, Feng X. J. Am. Chem. Soc. 2017; 139: 7513
- 25 Wang J, Xu X, Phan H, Herng TS, Gopalakrishna TY, Li G, Ding J, Wu J. Angew. Chem. Int. Ed. 2017; 56: 14154
- 26 Kato K, Osuka A. Angew. Chem. Int. Ed. 2019; 58: 8978
- 27a Hopkinson MN, Richter C, Schedler M, Glorius F. Nature 2014; 510: 485
- 27b Rottschäfer D, Blomeyer S, Neumann B, Stammler H.-G, Ghadwal RS. Chem. Eur. J. 2018; 24: 380
- 28a Ghadwal RS, Azhakar R, Roesky HW. Acc. Chem. Res. 2013; 46: 444
- 28b Wang Y, Robinson GH. Inorg. Chem. 2014; 53: 11815
- 28c Wang Y, Robinson GH. Dalton Trans. 2012; 337
- 28d Yao S, Xiong Y, Driess M. Acc. Chem. Res. 2017; 50: 2026
- 29a Walton JC, Brahmi MM, Monot J, Fensterbank L, Malacria M, Curran DP, Lacote E. J. Am. Chem. Soc. 2011; 133: 10312
- 29b Ueng SH, Solovyev A, Yuan X, Geib SJ, Fensterbank L, Lacote E, Malacria M, Newcomb M, Walton JC, Curran DP. J. Am. Chem. Soc. 2009; 131: 11256
- 29c Walton JC, McFadden TR, Curran DP. J. Am. Chem. Soc. 2017; 139: 16514
- 30a Melaimi M, Jazzar R, Soleilhavoup M, Bertrand G. Angew. Chem. Int. Ed. 2017; 56: 10046
- 30b Soleilhavoup M, Bertrand G. Acc. Chem. Res. 2015; 48: 256
- 30c Martin CD, Soleilhavoup M, Bertrand G. Chem. Sci. 2013; 4: 3020
- 30d Mondal KC, Roy S, Roesky HW. Chem. Soc. Rev. 2016; 45: 1080
- 30e Hansmann MM, Melaimi M, Munz D, Bertrand G. J. Am. Chem. Soc. 2018; 140: 2546
- 30f Hansmann MM, Melaimi M, Bertrand G. J. Am. Chem. Soc. 2018; 140: 2206
- 31a Vummaleti SV. C, Nelson DJ, Poater A, Gomez-Suarez A, Cordes DB, Slawin AM. Z, Nolan SP, Cavallo L. Chem. Sci. 2015; 6: 1895
- 31b Mondal KC, Roy S, Maity B, Koley D, Roesky HW. Inorg. Chem. 2016; 55: 163
- 32 Viehe HG, Janousek Z, Merenyi R, Stella L. Acc. Chem. Res. 1985; 18: 148
- 33a Li Y, Chan Y.-C, Leong B.-X, Li Y, Richards E, Purushothaman I, De S, Parameswaran P, So C.-W. Angew. Chem. Int. Ed. 2017; 56: 7573
- 33b Gu L, Zheng Y, Haldón E, Goddard R, Bill E, Thiel W, Alcarazo M. Angew. Chem. Int. Ed. 2017; 56: 8790
- 33c Kundu S, Sinhababu S, Luebben AV, Mondal T, Koley D, Dittrich B, Roesky HW. J. Am. Chem. Soc. 2018; 140: 151
- 33d Kundu S, Samuel PP, Sinhababu S, Luebben AV, Dittrich B, Andrada DM, Frenking G, Stückl AC, Schwederski B, Paretzki A, Kaim W, Roesky HW. J. Am. Chem. Soc. 2017; 139: 11028
- 33e Braunschweig H, Krummenacher I, Légaré M.-A, Matler A, Radacki K, Ye Q. J. Am. Chem. Soc. 2017; 139: 1802
- 34a Mahoney JK, Martin D, Moore CE, Rheingold AL, Bertrand G. J. Am. Chem. Soc. 2013; 135: 18766
- 34b Hansmann MM, Melaimi M, Bertrand G. J. Am. Chem. Soc. 2017; 139: 15620
- 34c Styra S, Melaimi M, Moore CE, Rheingold AL, Augenstein T, Breher F, Bertrand G. Chem. Eur. J. 2015; 21: 8441
- 34d Mahoney JK, Martin D, Thomas F, Moore CE, Rheingold AL, Bertrand G. J. Am. Chem. Soc. 2015; 137: 7519
- 35a Eymann LY. M, Tskhovrebov AG, Sienkiewicz A, Bila JL, Živković I, Rønnow HM, Wodrich MD, Vannay L, Corminboeuf C, Pattison P, Solari E, Scopelliti R, Severin K. J. Am. Chem. Soc. 2016; 138: 15126
- 35b Back J, Park J, Kim Y, Kang H, Kim Y, Park MJ, Kim K, Lee E. J. Am. Chem. Soc. 2017; 139: 15300
- 35c Wang Y, Hickox HP, Xie Y, Wei P, Blair SA, Johnson MK, Schaefer HF, Robinson GH. J. Am. Chem. Soc. 2017; 139: 6859
- 35d Kim Y, Lee E. Chem. Eur. J. 2018; 24: 19110
- 36a Ghadwal RS, Lamm J.-H, Rottschäfer D, Schürmann CJ, Demeshko S. Dalton Trans. 2017; 7664
- 36b Ho NK. T, Neumann B, Stammler H.-G, Menezes da Silva VH, Watanabe DG, Braga AA. C, Ghadwal RS. Dalton Trans. 2017; 12027
- 36c Ho NK. T, Reichmann SO, Rottschäfer D, Herbst-Irmer R, Ghadwal RS. Catalysts 2017; 7: 262
- 36d Rottschäfer D, Schürmann CJ, Lamm J.-H, Paesch AN, Neumann B, Ghadwal RS. Organometallics 2016; 35: 3421
- 36e Ghadwal RS, Reichmann SO, Herbst-Irmer R. Chem. Eur. J. 2015; 21: 4247
- 37a Rottschäfer D, Ebeler F, Strothmann T, Neumann B, Stammler H.-G, Mix A, Ghadwal RS. Chem. Eur. J. 2018; 24: 3716
- 37b Rottschäfer D, Neumann B, Stammler H.-G, Ghadwal RS. Chem. Eur. J. 2017; 23: 9044
- 37c Rottschäfer D, Neumann B, Stammler H.-G, Kishi R, Nakano M, Ghadwal RS. Chem. Eur. J. 2019; 25: 3244
- 37d Sharma M, Blomeyer S, Neumann B, Stammler H.-G, Ghadwal RS. Chem. Eur. J. 2019; 25: 8249
- 37e Rottschäfer D, Sharma MK, Neumann B, Stammler H.-G, Andrada DM, Ghadwal RS. Chem. Eur. J. 2019; 25: 8127
- 38 Ghadwal RS. Dalton Trans. 2016; 16081
- 39 Gorodetsky B, Ramnial T, Branda NR, Clyburne JA. C. Chem. Commun. 2004; 1972
- 40 McKenzie I, Brodovitch J.-C, Percival PW, Ramnial T, Clyburne JA. C. J. Am. Chem. Soc. 2003; 125: 11565
- 41 Ghadwal RS, Rottschäfer D, Schürmann CJ. Z. Anorg. Allg. Chem. 2016; 642: 1236
- 42 Aldeco-Perez E, Rosenthal AJ, Donnadieu B, Parameswaran P, Frenking G, Bertrand G. Science 2009; 326: 556
- 43 Rottschäfer D, Neumann B, Stammler H.-G, van Gastel M, Andrada DM, Ghadwal RS. Angew. Chem. Int. Ed. 2018; 57: 4765
- 44 Giffin NA, Hendsbee AD, Masuda JD. Acta Crystallogr., Sect. E: Struct. Rep. Online 2010; 66: o2194
- 45 Rottschäfer D, Ho NK. T, Neumann B, Stammler H.-G, van Gastel M, Andrada DM, Ghadwal RS. Angew. Chem. Int. Ed. 2018; 57: 5838
- 46 Rottschäfer D, Neumann B, Stammler H.-G, Andrada DM, Ghadwal RS. Chem. Sci. 2018; 9: 4970
- 47 Rottschäfer D, Busch J, Neumann B, Stammler H.-G, van Gastel M, Kishi R, Nakano M, Ghadwal RS. Chem. Eur. J. 2018; 24: 16537
- 48 Barry BM, Soper RG, Hurmalainen J, Mansikkamaki A, Robertson KN, McClennan WL, Veinot AJ, Roemmele TL, Werner-Zwanziger U, Boere RT, Tuononen HM, Clyburne JA. C, Masuda JD. Angew. Chem. Int. Ed. 2018; 57: 749
- 49a Antoni PW, Bruckhoff T, Hansmann MM. J. Am. Chem. Soc. 2019; 141: 9701
- 49b Antoni PW, Hansmann MM. J. Am. Chem. Soc. 2018; 140: 14823
- 50 Ravat P, Baumgarten M. Phys. Chem. Chem. Phys. 2015; 17: 983
- 51 Kamada K, Ohta K, Shimizu A, Kubo T, Kishi R, Takahashi H, Botek E, Champagne B, Nakano M. J. Phys. Chem. Lett. 2010; 1: 937
- 52a Ito S, Nagami T, Nakano M. J. Photochem. Photobiol., C 2018; 34: 85
- 52b Nakano M. Chem. Rec. 2017; 17: 27
- 52c Minami T, Ito S, Nakano M. J. Phys. Chem. Lett. 2013; 4: 2133
- 53a Messelberger J, Grünwald A, Pinter P, Hansmann MM, Munz D. Chem. Sci. 2018; 9: 6107
- 53b Chen M, Bae YJ, Mauck CM, Mandal A, Young RM, Wasielewski MR. J. Am. Chem. Soc. 2018; 140: 9184
- 53c Casanova D. Chem. Rev. 2018; 118: 7164
- 54 Fukuda K, Suzuki Y, Matsui H, Nagami T, Kitagawa Y, Champagne B, Kamada K, Yamamoto Y, Nakano M. ChemPhysChem 2017; 18: 142