Synthesis 2011(22): 3687-3691  
DOI: 10.1055/s-0030-1260250
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Synthesis of Mono- and Bis-N-Heterocyclic Carbene Copper(I) Complexes via Decarboxylative Generation of Carbenes

Tatiana Le Gall, Sandra Baltatu, Shawn K. Collins*
Department of Chemistry and the Centre for Green Chemistry and Catalysis, Université de Montréal, C.P. 6128 Succursale Centre-ville, Montréal, QC, H3C 3J7, Canada
e-Mail: shawn.collins@umontreal.ca;
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Publikationsverlauf

Received 7 July 2011
Publikationsdatum:
05. Oktober 2011 (online)

Abstract

Zwitterionic carboxylates can be thermally decarboxylated in the presence of copper salts to form NHC-copper com­plexes. The selective formation of either mono- or bis-NHC complexes is possible through simple control of the molar equivalents of the copper salt. A variety of different NHC ligands with either saturated or unsaturated backbones or bearing N-aryl or N-alkyl substituents can be complexed to copper.

    References

  • 1a Kaur H. Zinn FK. Stevens ED. Nolan SP. Organometallics  2004,  23:  1157 
  • 1b Díez-González S. Kaur H. Zinn FK. Stevens ED. Nolan SP. J. Org. Chem.  2005,  70:  4784 
  • 1c Díez-González S. Scott NM. Nolan SP. Organometallics  2006,  25:  2355 
  • 1d Díez-González S. Stevens ED. Scott NM. Petersen JL. Nolan SP. Chem. Eur. J.  2008,  14:  158 
  • 2 Welle A. Díez-González S. Tinant B. Nolan SP. Riant O. Org. Lett.  2006,  8:  6059 
  • 3a Delp SA. Munro-Leighton C. Goj LA. Ramírez MA. Gunnoe TB. Petersen JL. Boyle PD. Inorg. Chem.  2007,  46:  2365 
  • 3b Munro-Leighton C. Blue ED. Gunnoe TB. J. Am. Chem. Soc.  2006,  128:  1446 
  • 3c Munro-Leighton C. Delp SA. Blue ED. Gunnoe TB. Organometallics  2007,  26:  1483 
  • 4a Trost BM. Dong G. J. Am. Chem. Soc.  2006,  128:  6054 
  • 4b Liu R. Herron SR. Fleming SA. J. Org. Chem.  2007,  72:  5587 
  • 5 Fructos MR. Belderrain TR. Nicasio MC. Nolan SP. Kaur H. Díaz-Requejo MM. Pérez PJ. J. Am. Chem. Soc.  2004,  126:  10846 
  • 6 Lebel H. Davi M. Díez-González S. Nolan SP. J. Org. Chem.  2007,  72:  144 
  • 7 Díez-González S. Correa A. Cavallo L. Nolan SP. Chem. Eur. J.  2006,  12:  7558 
  • 8a Dupuy S. Lazreg F. Slawin AMZ. Cazin CSJ. Nolan SP. Chem. Commun.  2011,  47:  5455 
  • 8b Boogaerts IIF. Nolan SP. Chem. Commun.  2011,  47:  3021 
  • 8c Boogaerts IIF. Fortman GC. Furst MRL. Cazin CSJ. Nolan SP. Angew. Chem. Int. Ed.  2010,  49:  8674 
  • 8d Fortman GC. Poater A. Levell JW. Gaillard S. Slawin AMZ. Samuel IDW. Cavallo L. Nolan SP. Dalton Trans.   2010,  39:  10382 
  • 9a Van Veldhuizen JJ. Campbell JE. Giudici RE. Hoveyda AH. J. Am. Chem. Soc.  2005,  127:  6877 
  • 9b Tominaga S. Oi Y. Kato T. An DK. Okamoto S. Tetrahedron Lett.  2004,  45:  5585 
  • 9c Winn CL. Guillen F. Pytkowicz J. Roland S. Mangeney P. Alexakis A. J. Organomet. Chem.  2005,  690:  5672 
  • 9d Martin D. Kehrli S. d’Augustin M. Clavier H. Mauduit M. Alexakis A. J. Am. Chem. Soc.  2006,  128:  8416 
  • 9e Brown MK. May TL. Baxter CA. Hoveyda AH. Angew. Chem. Int. Ed.  2007,  46:  1097 
  • 9f Lee K.-S. Brown MK. Hird AW. Hoveyda AH. J. Am. Chem. Soc.  2006,  128:  7182 
  • 10 Grandbois A. Mayer M.-E. Bedard M. Collins SK. Michel T. Chem. Eur. J.  2009,  15:  9655 
  • For examples using Cu(I) see:
  • 11a Mankad NP. Gray TG. Laitar DS. Sadighi JP. Organometallics  2004,  23:  1191 
  • 11b Schneider N. César V. Bellemin-Laponnaz S. Gade LH. J. Organomet. Chem.  2005,  690:  5556 
  • 11c Michon C. Ellern A. Angelici RJ. Inorg. Chim. Acta  2006,  359:  4549 
  • For examples using Cu(II) see:
  • 11d Hu X. Castro-Rodriguez I. Meyer K. J. Am. Chem. Soc.  2003,  125:  12237 
  • 11e Yun J. Kim D. Yun H. Chem. Commun.  2005,  5181 
  • For examples using Cu(I) see:
  • 12a Arnold PL. Scarisbrick AC. Blake AJ. Wilson C. Chem. Commun.  2001,  2340 
  • 12b Wan X.-J. Xu F.-B. Li Q.-S. Song H.-B. Zhang Z.-Z. Inorg. Chem. Commun.  2005,  8:  1053 
  • 12c Winkelmann O. Näther C. Lüning U. J. Organomet. Chem.  2008,  693:  923 
  • For an example using Cu(II) see:
  • 12d Larsen AO. Leu W. Nieto Oberhuber C. Campbell JE. Hoveyda AH. J. Am. Chem. Soc.  2004,  126:  11130 
  • 13a Citadelle CA. Le Nouy E. Bisaro F. Slawin AMZ. Cazin CSJ. Dalton Trans.   2010,   39:   4489 
  • 13b Tulloch AAD. Danopoulos AA. Kleinhenz S. Light ME. Hursthouse MB. Eastham G. Organometallics  2001,  20:  2027 
  • 13c Simonovic S. Whitwood AC. Clegg W. Harrington RW. Hursthouse MB. Male L. Douthwaite RE. Eur. J. Inorg. Chem.  2009,  1786 
  • 14a Sauvage X. Demonceau A. Delaude L. Macromol. Symp.  2010,  293:  28 
  • 14b Sauvage X. Demonceau A. Delaude L. Adv. Synth. Catal.  2009,  351:  2031 
  • 14c Delaude L. Sauvage X. Demonceau A. Wouters J. Organometallics  2009,  28:  4056 
  • 14d Voutchkova AM. Feliz M. Clot E. Eisenstein O. Crabtree RH. J. Am. Chem. Soc.  2007,  129:  12834 
  • 14e Voutchkova AM. Appelhans LN. Chianese AR. Crabtree RH. J. Am. Chem. Soc.  2005,  127:  17624 
  • 18 Tudose A. Delaude L. André B. Demonceau A. Tetrahedron Lett.  2006,  47:  8529 
  • 19 Duong H. Tekavec T. Arif A. Louie J. Chem. Commun.  2004,  112 
  • 21 Diez-Gonzalez S. Scott N. Nolan S. Organometallics  2006,  25:  2355 
  • 22 Kaur H. Kauer Zinn F. Stevens E. Nolan S. Organometallics  2004,  23:  1157 
  • 23 Goj L. Blue E. Delp S. Gunnoe T. Cundari T. Pierpont A. Peterson J. Boyle P. Inorg. Chem.  2006,  45:  9032 
  • 24 Diez-Gonzalez S. Stevens ED. Nolan SP. Chem. Commun.  2008,  4747 
  • 25 Diez-Gonzalez S. Escudero-Adan EC. Benet-Buchholz J. Stevens ED. Slawin AMZ. Nolan SP. Dalton Trans.  2010,  39:  7595 
  • 26 Broggi J. Diez-Gonzalez S. Petersen J. Berteina-Raboin S. Nolan S. P. Agrofoglio L. Synthesis  2008,  141 
15

One advantage of the decarboxylation method is the absence of strong bases such as potassium tert-butoxide, which has been shown to react with Cu(NHC)2X complexes to form an unwanted byproduct Cu(NHC)(Ot-Bu). See ref. 7.

16

Although complexes 6a-c are depicted as ionic, at this time there is yet no proof as to whether the halide counterions are ligated to the copper atom or not.

17

The ¹H and ¹³C NMR spectra for Cu(NHC)X and Cu(NHC)2X complexes are very similar. The complexes can be easily distinguished by TLC [the Cu(NHC)2X complexes are much more polar than the analogous Cu(NHC)X complexes] and by MS.

20

Pevere V.; FR 2,921,924, 2009