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Synlett 2011(7): 951-954  
DOI: 10.1055/s-0030-1259723
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Efficient Aqueous-Phase Heck Reaction Catalyzed by a Robust Hydrophilic Pyridine-Bridged Bisbenzimidazolylidene-Palladium Pincer Complex

Zhixun Wang, Xike Feng, Weiwei Fang, Tao Tu*
Department of Chemistry, Fudan University, 220 Handan Road, 200433 Shanghai, P. R. of China
Fax: +86(21)55664250; e-Mail: taotu@fudan.edu.cn;
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Publication History

Received 20 December 2010
Publication Date:
10 March 2011 (online)

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Abstract

The first efficient example of NHC-palladium pincer complex catalyzed aqueous Heck reaction with extremely low catalyst loading was realized without obvious hydrolysis of products by using a robust hydrophilic pyridine-bridged bisbenzimidazolylidene-palladium complex as a molecular catalyst, which tolerated various electronic properties of substituted functional groups in arenes.

Key words

aqueous phase - benzimidazole - Heck reaction - N-heterocyclic carbene - palladium

    References and Notes

  • 1a Heck RF. Acc. Chem. Res.  1979,  12:  146 
    Google Scholar
  • 1b Heck RF. Nolley JP. J. Org. Chem.  1972,  37:  2320 
    Google Scholar
  • 1c Mizoroki T. Mori K. Ozaki A. Bull. Chem. Soc. Jpn.  1971,  44:  581 
    Google Scholar
  • For selected recent reviews of Heck reaction, see:
  • 2a Torborg C. Beller M. Adv. Synth. Catal.  2009,  351:  3027 
    Google Scholar
  • 2b Nicolaou KC. Bulger PG. Sarlah D. Angew. Chem. Int. Ed.  2005,  44:  4442 
    Google Scholar
  • 2c Dounay AB. Overman LE. Chem. Rev.  2003,  103:  2945 
    Google Scholar
  • 2d Whitcombe NJ. Hii KK. Gibson SE. Tetrahedron  2001,  57:  7449 
    Google Scholar
  • 2e Beletskaya IP. Cheprakov AV. Chem. Rev.  2000,  100:  3009 
    Google Scholar
  • 3a Metal-Catalyzed Cross-Coupling Reactions   2nd ed.:  de Meijere A. Diederich F. John Wiley and Sons; New York: 2004. 
    Google Scholar
  • 3b Transition Metals for Organic Synthesis Building Blocks and Fine Chemicals   Vol. 1:  Beller M. Bolm C. Wiley-VCH; Weinheim: 1998. 
    Google Scholar
  • 3c Comprehensive Organic Synthesis   Vol. 4:  Trost BM. Fleming I. Pergamon Press; Oxford: 1991. 
    Google Scholar
  • 3d Heck RF. Org. React.  1982,  27:  345 
    Google Scholar
  • 4 Birkholz M.-N. Freixa Z. van Leeuwen PWNM. Chem. Soc. Rev.  2009,  38:  1099 ; and references therein
    CrossrefGoogle Scholar
  • 5a Alonso DA. Nájera C. Chem. Soc. Rev.  2010,  39:  2891 
    Google Scholar
  • 5b Pan D. Jiao N. Synlett  2010,  1577 
    Google Scholar
  • 5c Modern Arylation Methods   Ackermann L. Wiley-VCH; Weinheim: 2009. 
    Google Scholar
  • 6a Chanda A. Fokin VV. Chem. Rev.  2009,  109:  725 
    Google Scholar
  • 6b Carril M. SanMartin R. Dominguez E. Chem. Soc. Rev.  2008,  37:  639 
    Google Scholar
  • 6c Comprehensive Organic Reactions in Aqueous Media   2nd ed.:  Li CJ. Chan TH. Wiley; New York: 2007. 
    Google Scholar
  • 6d Li CJ. Chem. Rev.  2005,  105:  3095 
    Google Scholar
  • 6e Aqueous-Phase Organometallic Catalysis: Concepts and Applications   2nd ed.:  Cornils B. Herrmann WA. Wiley-VCH; Weinheim: 2004. 
    Google Scholar
  • 6f Organic Synthesis in Water   Grieco PA. Blackie Academic and Professional; London: 1998. 
    Google Scholar
  • 7a Mauger CC. Mignani GA. Aldrichimica Acta  2006,  39:  17 
    Google Scholar
  • 7b Zapf A. Beller M. Chem. Commun.  2005,  431 
    Google Scholar
  • 7c Jeffery T. Tetrahedron Lett.  1994,  35:  3051 
    Google Scholar
  • For recent reviews, see:
  • 8a Hahn FE. Jahnke MC. Angew. Chem. Int. Ed.  2008,  47:  3122 
    Google Scholar
  • 8b Crabtree RH. Coord. Chem. Rev.  2007,  251:  596 
    Google Scholar
  • 8c N-Heterocyclic Carbenes in Transition Metal Catalysis, In Topics in Organometallic Chemistry   Vol. 21:  Glorius F. Springer; Berlin: 2007.  p.1-218  
    Google Scholar
  • 8d Marion N. Díez-González S. Nolan SP. Angew. Chem. Int. Ed.  2007,  46:  2988 
    Google Scholar
  • 8e Kühl O. Chem. Soc. Rev.  2007,  36:  592 
    Google Scholar
  • 8f Hahn FE. Angew. Chem. Int. Ed.  2006,  45:  1348 
    Google Scholar
  • 9 Fleckenstein C. Roy S. Leuthäußer S. Plenio H. Chem. Commun.  2007,  2870 
    Google Scholar
  • 10a Tu T. Bao X. Assenmacher W. Peterlik H. Daniels J. Dötz KH. Chem. Eur. J.  2009,  15:  1853 
    Google Scholar
  • 10b Tu T. Assenmacher W. Peterlik H. Schnakenburg G. Dötz KH. Angew. Chem. Int. Ed.  2008,  47:  7127 
    Google Scholar
  • 10c Tu T. Assenmacher W. Peterlik H. Weisbarth R. Nieger M. Dötz KH. Angew. Chem. Int. Ed.  2007,  46:  6368 
    Google Scholar
  • 11a Tu T. Feng X. Wang Z. Liu X. Dalton Trans.  2010,  10598 
    Google Scholar
  • 11b Tu T. Mao H. Herbert C. Xu M. Dötz KH. Chem. Commun.  2010,  46:  7796 
    Google Scholar
  • 11c Tu T. Malineni J. Bao X. Dötz KH. Adv. Synth. Catal.  2009,  351:  1029 
    Google Scholar
  • 11d Tu T. Malineni J. Dötz KH. Adv. Synth. Catal.  2008,  350:  1791 
    Google Scholar
  • 13a Peris E. Crabtree RH. Coord. Chem. Rev.  2004,  248:  2239 
    Google Scholar
  • 13b Peris E. Loch JA. Mata J. Crabtree RH. Chem. Commun.  2001,  201 
    Google Scholar
12

General Procedure for the Aqueous Heck Reactions Catalyzed by Palladium Complex 2
Palladium pincer complex 2 (50 ppm) was added to the 5 mL flask containing iodoarene (1 mmol), acrylate (1.5 mmol), Et3N (2.5 mmol), and TBAI (1 mmol) in H2O (2 mL) under air. After heating at 100 ˚C for certain time (monitored by TLC), the reaction mixture was allowed to cool to r.t., and the aqueous layer was extracted with EtOAc (5 × 3 mL). The combined organic extracts were dried over anhydrous Na2SO4. After evaporation under vacuum, the crude product was purified by flash column chromatography (hexane-EtOAc, 100:1).