On the mechanism of palladium-catalyzed coupling of haloaryls to biaryls in water with zinc

Organic Letters

Volumn 2, Issue 2, 2000, Pages 211-214

  Mukhopadhyay, Sudip ^a   Rothenberg, Gadi ^b   Gitis, Diana ^a   Sasson, Yoel ^a  

^a HEBREW UNIVERSITY OF JERUSALEM   (Israel)

^b UNIVERSITY OF YORK   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0038325003     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol9912938     Document Type: Article

References (27)

1. For representative reviews on biaryl preparation methods and applications, see: (a) Bringmann, G.; Walter, R.; Weirich, R. Angew. Chem., Int. Ed. Engl. 1990, 29, 977.
2. (b) Sainsbury, M. Tetrahedron 1980, 36, 3327.
3. See also: (c) Stinson, S. C. Chem. Eng. News 1999, 69.
4. (a) Ullmann, F. Ber. 1903, 36, 2389.
5. (b) Fanta, P. E. Synthesis 1974, 9.
6. (a) Miyamura, N.; Yanagi, T.; Suzuki, A. Synth. Commun. 1981, 11, 513.
7. (b) Suzuki, A. Pure Appl. Chem. 1991, 63, 419.
8. (c) Moreno-Mañas, M.; Pérez, M.; Pleixats, R. J. Org. Chem. 1996, 61, 2346.
9. For an excellent recent monograph on palladium catalysis see: Tsuji, J. Palladium Reagents and Catalysts: Wiley: New York, 1993.
10. (a) Hennings, D. D.; Iwama T.; Rawal, V. H. Org. Lett. 1999, 1, 1205.
11. (b) Hassan, J.; Penalva, V.; Lavenot, L.; Gozzi, C.; Lemaire, M. Tetrahedron 1998, 54, 13793.
12. Mukhopadhyay, S.; Rothenberg, G.; Wiener H.; Sasson, Y. Tetrahedron 1999, 55, 14763.
13. (a) Bamfield, P.; Quan, P. M. Synthesis 1978, 537.
14. (b) Mukhopadhyay, S.; Rothenberg, G.; Gitis, D.; Wiener H.; Sasson, Y. J. Chem. Soc., Perkin Trans. 2 1999, 2481.
15. Venkatraman, S.; Li, C.-J. Org. Lett. 1999, 1, 1133.
16. 4Si) 7.39 (2H, tt, aromatic 4,4′-H), 7.46 (4H, qt, aromatic 3,3′,5,5′-H), 7.59 (4H, dq, aromatic 2,2′,6,6′-H). Good agreement was found with literature values (Kamewaza, N. J. Magn. Reson. 1973, 11, 88). Please refer to the Supporting Information for details of the synthesis of compounds 2b and 2d.
17. 4Si) 7.39 (2H, tt, aromatic 4,4′-H), 7.46 (4H, qt, aromatic 3,3′,5,5′-H), 7.59 (4H, dq, aromatic 2,2′,6,6′-H). Good agreement was found with literature values (Kamewaza, N. J. Magn. Reson. 1973, 11, 88). Please refer to the Supporting Information for details of the synthesis of compounds 2b and 2d.
18. Please refer to the Supporting Information for details of the kinetic studies.
19. (a) To ensure that reaction rates were not mass transfer controlled, agitation speed was varied from 200 to 950 rpm. Above 800 rpm, no increase in conversion was detected. Thus, all measurements pertain to 950 rpm stirring. (b) For reactions at different chlorobenzene concentrations, xylene was added to make up for the volume of the organic phase.
20. (a) Cf. Marques, C. A.; Selva, M.; Tundo, P. J. Org. Chem. 1994, 59, 3830, where hydro-dehalogenation was found to be of zero order in the substrate.
21. (b) Blackmond, D. G.; Rosner, T.; Pfaltz, A. Org. Proc. Res. Dev. 1999, 3, 275.
22. (a) Rothenberg, G.; Barak, G.; Sasson, Y. Tetrahedron 1999, 55, 6301.
23. (b) Aït-Mohand, S.; Hénin, F.; Muzart, J. Tetrahedron Lett. 1995, 36, 2473.
24. (c) Bouquillon, S.; du Moulinet d'Hardemare, A.; Averbuch-Pouchot, M.; Hénin, F.; J. Muzart, J. Polyhedron 1999, 18, 3511-3516.
25. For a detailed discussion of this reaction see: Mukhopadhyay, S.; Rothenberg, G.; Wiener, H.; Sasson, Y. J. Chem. Soc., Perkin Trans. 2, 1999, in press. See also ref 6.
26. No chlorobiphenyls were observed, so we may disregard the possibility of phenyl radicals attacking substrate molecules in this system. Thus, it is probable that the aryl radicals couple on the catalyst surface, followed by desorption of biphenyl.
27. 2O (3 × 40 mL) and MeOH (3 × 10 mL). The catalyst retained >78% of its activity on a consecutive run with fresh zinc.