Synlett 2010(2): 313-316  
DOI: 10.1055/s-0029-1219184
CLUSTER
© Georg Thieme Verlag Stuttgart ˙ New York

Iron-Catalyzed Direct Arylation of Aryl Pyridines and Imines Using Oxygen as an Oxidant

Naohiko Yoshikai, Arimasa Matsumoto, Jakob Norinder, Eiichi Nakamura*
Department of Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
Fax: +81(3)58006889; e-Mail: nakamura@chem.s.u-tokyo.ac.jp;
Further Information

Publication History

Received 2 October 2009
Publication Date:
08 January 2010 (online)

Abstract

An iron-catalyzed ortho C-H bond arylation reaction of an aryl pyridine or imine with an arylzinc reagent, which previously required the use of a rather expensive organodichloride as an oxidant, can now be achieved under oxygen atmosphere. By slowly introducing oxygen into the reaction, oxidative cross-coupling of the two reactants took place smoothly to give a biaryl product in moderate to good yield.

    References and Notes

  • 2a Kakiuchi F. Kochi T. Synthesis  2008,  3013 
  • 2b Godula K. Sames D. Science  2006,  312:  67 
  • 2c Handbook of C-H Transformations   Dyker G. Wiley-VCH; Weinheim: 2005. 
  • 2d Kakiuchi F. Chatani N. Adv. Synth. Catal.  2003,  345:  1077 
  • 3a Chen X. Engle KM. Wang D.-H. Yu J.-Q. Angew. Chem. Int. Ed.  2009,  48:  5094 
  • 3b Li B.-J. Yang S.-D. Shi Z.-J. Synlett  2008,  949 
  • 3c Alberico D. Scott ME. Lautens M. Chem. Rev.  2007,  107:  174 
  • 4a Oi S. Fukita S. Inoue Y. Chem. Commun.  1998,  2439 
  • 4b Chen X. Li J.-J. Hao X.-S. Goodhue CE. Yu J.-Q. J. Am. Chem. Soc.  2006,  128:  78 
  • 4c Kawai H. Kobayashi Y. Oi S. Inoue Y. Chem. Commun.  2008,  1464 
  • 5a Kakiuchi F. Kan S. Igi K. Chatani N. Murai S. J. Am. Chem. Soc.  2003,  125:  1698 
  • 5b Kakiuchi F. Matsuura Y. Kan S. Chatani N. J. Am. Chem. Soc.  2005,  127:  5936 
  • 5c Park YJ. Jo E.-A. Jun C.-H. Chem. Commun.  2005,  1185 
  • 5d Chen X. Goodhue CE. Yu J.-Q. J. Am. Chem. Soc.  2006,  128:  12634 
  • 5e Giri R. Maugel N. Li J.-J. Wang D.-H. Breazzano SP. Saunders LB. Yu J.-Q. J. Am. Chem. Soc.  2007,  72:  3600 
  • 5f Ueno S. Chatani N. Kakiuchi F. J. Org. Chem.  2007,  130:  7190 
  • 5g Pastine SJ. Gribkov DV. Sames D. J. Am. Chem. Soc.  2007,  129:  14220 
  • 5h Wang D.-H. Wasa M. Giri R. Yu J.-Q. J. Am. Chem. Soc.  2008,  130:  7190 
  • 5i Yang S.-D. Sun C.-L. Fang Z. Li B.-J. Li Y.-Z. Shi Z.-J. Angew. Chem. Int. Ed.  2008,  47:  1473 
  • 5j Shi B.-F. Maugel N. Zhang Y.-H. Yu J.-Q. Angew. Chem. Int. Ed.  2008,  47:  4882 
  • 5k Wang D.-H. Mei T.-S. Yu J.-Q. J. Am. Chem. Soc.  2008,  130:  17676 
  • 5l Vogler T. Studer A. Org. Lett.  2008,  10:  129 
  • 5m Ban I. Sudo T. Taniguchi T. Itami K. Org. Lett.  2008,  10:  3607 
  • 5n Kirchberg S. Vogler T. Studer A. Synlett  2008,  2841 
  • 5o Miyamura S. Tsurugi H. Satoh T. Miura M. J. Organomet. Chem.  2008,  693:  2438 
  • 5p Ueno S. Kochi T. Chatani N. Kakiuchi F. Org. Lett.  2009,  11:  855 
  • 5q Kitazawa K. Kochi T. Sato M. Kakiuchi F. Org. Lett.  2009,  11:  1951 
  • 5r Wei Y. Kan J. Su W. Hong M. Org. Lett.  2009,  11:  3346 
  • 5s Zhou H. Chung W.-J. Xu Y.-H. Loh T.-P. Chem. Commun.  2009,  3472 
  • 6a Yang S.-D. Li B.-J. Wan X.-B. Shi Z.-J. J. Am. Chem. Soc.  2007,  129:  6066 
  • 6b Zhou H. Xu Y.-H. Chung W.-J. Loh T.-P. Angew. Chem. Int. Ed.  2009,  48:  5355 
  • 7a Nakamura M. Hirai A. Nakamura E. J. Am. Chem. Soc.  2000,  122:  978 
  • 7b Nakamura M. Matsuo K. Inoue T. Nakamura E. Org. Lett.  2003,  5:  1373 
  • 7c Nakamura M. Matsuo K. Ito S. Nakamura E. J. Am. Chem. Soc.  2004,  126:  3686 
  • 7d Nakamura M. Ito S. Matsuo K. Nakamura E. Synlett  2005,  1794 
  • 7e Hatakeyama T. Kondo Y. Fujiwara Y.-i. Takaya H. Ito S. Nakamura E. Nakamura M. Chem. Commun.  2009,  1216 
  • 7f Ito S. Fujiwara Y.-i. Nakamura E. Nakamura M. Org. Lett.  2009,  11:  4306 
  • 8a Bolm C. Legros J. Le Paih J. Zani L. Chem. Rev.  2004,  104:  6217 
  • 8b Enthaler S. Junge K. Beller M. Angew. Chem. Int. Ed.  2008,  47:  3317 
  • 8c Sherry BD. Fürstner A. Acc. Chem. Res.  2008,  41:  1500 
  • 8d Iron Catalysis in Organic Chemistry   Plietker B. Wiley-VCH; Weinheim: 2008. 
  • 9a Norinder J. Matsumoto A. Yoshikai N. Nakamura E. J. Am. Chem. Soc.  2008,  130:  5858 
  • 9b Yoshikai N. Matsumoto A. Norinder J. Nakamura E. Angew. Chem. Int. Ed.  2009,  48:  2925 
  • 9c Ilies L. Tsuji H. Nakamura E. Org. Lett.  2009,  11:  3966 
  • 11 Cahiez G. Moyeux A. Buendia J. Duplais C. J. Am. Chem. Soc.  2007,  129:  13788 
  • 13 Buchwald SL. Bolm C. Angew. Chem. Int. Ed.  2009,  48:  5586 
  • 14 Klein H.-F. Camadanli S. Beck R. Leukel D. Flörke U. Angew. Chem. Int. Ed.  2005,  44:  975 
  • 15a Ferreira EM. Stoltz BM. J. Am. Chem. Soc.  2003,  125:  9578 
  • 15b Beck EM. Grimster NP. Hatley R. Gaunt MJ. J. Am. Chem. Soc.  2006,  128:  2528 
  • 15c Basle O. Li C.-J. Green Chem.  2007,  9:  1047 
  • 15d Zhang Y.-H. Shi B.-F. Yu J.-Q. J. Am. Chem. Soc.  2009,  131:  5072 
1

Present address: N. Yoshikai, Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.

10

The reaction needs 1 equiv of the zinc reagent for removal of the ortho hydrogen atom, 1 equiv for arylation, and small amount for generation of the active catalyst.9a

12

The yields of biphenyl and phenol were typically in the range of 50-150% and 120-180%, respectively (based on the substrate).

16

A Typical Procedure for Arylation of 2-Arylpyridine An oven-dried Schlenk tube was charged with ZnCl2˙TMEDA (505 mg, 2.0 mmol), 2,2′-bipyridine (9.3 mg, 60 µmol), and 2-arylpyridine (0.40 mmol) and cooled in an ice bath, followed by addition of a THF solution of PhMgBr (1.0 M, 4.0 mL, 4.0 mmol). After stirring for 1 h, a THF solution of FeCl3 (0.10 M, 0.60 mL, 60 µmol) was added to the mixture. Then oxygen gas (10 mL, 0.45 mmol) was allowed to diffuse into the reaction by attaching a gastight syringe fitted with a 20G needle (38 mm). The reaction mixture was stirred for 36 h with gradual warming to r.t., while every 12 h the gastight syringe was filled with fresh O2 gas. The reaction was quenched by the addition of sat. aq solution of Rochelle salt and extracted with EtOAc (3 × 5 mL). The organic solution was dried over Na2SO4 and concentrated under reduced pressure. The crude product was purified by silica gel chromatography to afford the arylation product.
A Typical Procedure for Arylation of Aryl Imine The reaction was carried out by the same procedure as above except for the use of 4,4′-di-tert-butyl-2,2′-bipyridine (16.1 mg, 60 µmol) instead of 2,2′-bipyridine. The reaction was quenched by the addition of 3 M HCl aq (5 mL), and the resulting mixture was stirred for 3 h at r.t. Further workup and purification was carried out in a similar manner as above to obtain the biaryl ketone product.
2-(4,5-Dimethoxybiphenyl-2-yl)pyridine (2f)
Mp 97.4-98.2 ˚C. IR (powder): 3062, 3035, 3008, 2964, 2933, 2838, 1688, 1598, 1580, 1520, 1478, 1453, 1441, 1385, 1351, 1320, 1273, 1260, 1243, 1179, 1113, 1081, 1038, 1011, 973, 924, 888, 818, 791, 770, 743, 702 cm. ¹H NMR (500 MHz, CDCl3): δ = 8.54 (d, J = 5.8 Hz, 1 H), 7.24-7.21 (m, 2 H), 7.15-7.12 (m, 3 H), 7.09-7.07 (m, 2 H), 6.98-6.95 (m, 1 H), 6.82 (s, 1 H), 6.71 (d, J = 8.0 Hz, 1 H), 3.89 (s, 3 H), 3.85 (s, 3 H). ¹³C NMR (125 MHz, CDCl3): δ = 158.7, 149.2, 148.8, 148.3, 141.2, 135.0, 133.3, 131.8, 129.7 (2 C), 128.0 (2 C), 126.5, 125.5, 120.9, 113.3, 113.1, 55.9, 55.8. HRMS (APCI): m/z calcd for C19H18NO2 + [M + H]+: 292.13375; found: 292.13331.
2-(5,6-Dimethoxybiphenyl-2-yl)pyridine (2g)
Mp 102.0-103.2 ˚C. IR (powder): 3058, 3000, 2962, 2931, 2834, 1582, 1563, 1519, 1485, 1428, 1407, 1279, 1256, 1219, 1162, 1117, 1108, 1009, 797, 776, 747, 718, 700, 685 cm. ¹H NMR (500 MHz, CDCl3): δ = 8.56 (d, J = 5.2 Hz, 1 H), 7.46 (d, J = 8.6 Hz, 1 H), 7.30-7.21 (m, 4 H), 7.18-7.16 (m, 2 H), 7.05 (d, J = 8.6 Hz, 1 H), 7.02-6.95 (m, 1 H), 6.69 (d, J = 8.0 Hz, 1 H), 3.95 (s, 3 H), 3.50 (s, 3 H). ¹³C NMR (125 MHz, CDCl3): δ = 158.6, 153.1, 149.1, 146.4, 136.5, 135.3, 134,9, 133.6, 130.8 (2 C), 127.6 (2 C), 126.7, 126.0, 125.2, 120.8, 111,6, 60.4, 55.9. HRMS (APCI): m/z calcd for C19H18NO2 + [M + H]+: 292.13375; found: 292.13395.
1-(4′-Fluorobiphenyl-2-yl)ethanone (2l)
IR (neat): 3062, 3043, 3025, 3002, 2971, 1684, 1607, 1598, 1513, 1474, 1443, 1355, 1287, 1268, 1221, 1160, 1117, 1096, 1077, 1042, 1017, 1007, 955, 837, 820, 802, 750, 720, 671 cm. ¹H NMR (500 MHz, CDCl3): δ = 7.56-7.54 (m, 1 H), 7.52-7.49 (m, 1 H), 7.43-7.40 (m, 1 H), 7.36-7.34 (m, 1 H), 7.32-7.29 (m, 2 H), 7.14-7.09 (m, 2 H), 2.05 (s, 3 H). ¹³C NMR (125 MHz, CDCl3): δ = 204.4, 162.6 (d, ¹ J C-F = 246.8 Hz), 140.7, 139.3, 136.7 (d, 4 J C-F = 3.6 Hz), 130.7, 130.4 (d, ³ J C-F = 8.4 Hz, 2 C), 130.3, 127.9, 127.5, 115.6 (d, ² J C-F = 21.5 Hz, 2 C), 30.3. HRMS (APCI): m/z calcd for C14H12FO+ [M + H]+: 215.0872; found: 215.0875.