Palladium-Catalyzed Homocoupling of Arylboronic Acids and Esters Using Fluoride in Aqueous Solvents

Abstract

Homocoupling of both arylboronic acids and esters has been found to proceed using catalytic amounts of Pd^II and stoichiometric amounts of TBAF under air atmosphere at room temperature, offering a mild and efficient protocol for the synthesis of symmetrical biaryls via C(sp ²)-C(sp ²) bond formation. Aryl boronic acids bearing bromide substitution form polyphenylenes.

Key words

boronic acids - palladium - fluoride - biaryls - water

References

• 1a Miyaura N. Suzuki A. Chem. Rev.  1995,  95:  2457 ; and references cited therein
• 1b Suzuki A. In Metal-Catalyzed Cross-Coupling Reaction   Diederich F. Stang P. Wiley-VCH; Weinheim: 1998.  p.49-97  
• 1c Suzuki A. J. Organomet. Chem.  1999,  576:  147 
• 2a Hassan J. Penalva V. Lavenot L. Gozzi C. Lemaire M. Tetrahedron  1998,  54:  13793 
• 2b Nicolaou KC. Boddy CNC. Braso S. Winssinger N. Angew. Chem. Int. Ed.  1999,  38:  2096 
• 3a Taylor PN. O’Connell MJ. McNeill LA. Hall MJ. Aplin RT. Anderson HL. Angew. Chem. Int. Ed.  2000,  39:  3456 
• 3b Step Growth Polymers for High-Performance Materials   Hedrick JL. Labadie JW. ACS Symposium Series 624; American Chemical Society; Washington, DC: 1996. 
• 4 Mézlová M. Petříčková H. Maloň P. Kozmík V. Svoboda J. Collect. Czech. Chem. Commun.  2003,  68:  1020 
• 5 Stearman CJ. Behar V. Tetrahedron Lett.  2002,  43:  1943 ; and references cited therein
• See for example:
• 6a Floyd AJ. Dyke SF. Ward SE. Chem. Rev.  1976,  76:  509 
• 6b Lourak M. Vanderese R. Fort Y. Caubère P. J. Org. Chem.  1989,  54:  4840 
• 6c Percec V. Bae J.-Y. Zhao M. Hill DH. J. Org. Chem.  1995,  60:  176 ; and references therein
• 7 Wong MS. Zhang XL. Tetrahedron Lett.  2001,  42:  4087 
• 8 Parrish JP. Jung YC. Floyd RJ. Jung KW. Tetrahedron Lett.  2002,  43:  7899 ; and references therein
• 9 Lei A. Zhang X. Tetrahedron Lett.  2002,  43:  2525 
• 10 Fang H. Yan J. Wang B. Molecules  2004,  9:  178 
• 11a Yoshida H. Yamaryo Y. Ohshita J. Kunai A. Tetrahedron Lett.  2003,  44:  1541 
• 11b The same authors also reported homocoupling reactions with arylsilanes using a biphasic system DMSO-H₂O at 50 °C: Yoshida H. Yamaryo Y. Ohshita J. Kunai A. Chem. Commun.  2003,  1510 
• 12 Demir AS. Reis O. Emrullahoglu M. J. Org. Chem.  2003,  68:  578 
• 13a Shen W. Tetrahedron Lett.  1997,  38:  5575 ; and references cited therein
• 13b Kabalka GW. Namboodiri V. Wang L. Chem. Commun.  2001,  775 
• 13c Basu B. Das P. Bhuiyan MMH. Jha S. Tetrahedron Lett.  2003,  44:  3817 
• For the formation of hyperbranched polyphenylenes by Pd(0)-catalyzed aryl-aryl coupling reactions, see:
• 14a Kim YH. Webster OW. Macromolecules  1992,  25:  5561 
• 14b Kim S. Jackiw J. Robinson E. Schanze KS. Reynolds JR. Baur J. Rubner MF. Boils D. Macromolecules  1998,  31:  964 ; and references cited therein
• 15a Jung YC. Mishra RK. Yoon CH. Jung KW. Org. Lett.  2003,  5:  2231 
• 15b Rh-catalyzed coupling of arylboronic acids to olefins has been reported to be crucially dependent on the presence of water and base: Lautens M. Roy A. Fukuoka K. Fagnou K. Martín-Matute B. J. Am. Chem. Soc.  2001,  123:  5358 
• 16 Pierre Genet J. Savignac M. J. Organomet. Chem.  1999,  576:  305 
• 17a Springsteen G. Wang B. Tetrahedron  2002,  58:  5291 
• 17b Ni W. Fang H. Springsteen G. Wang B. J. Org. Chem.  2004,  69:  1999 
• 19 Vedejs E. Chapman RW. Fields SC. Lin S. Schrimpf MR. J. Org. Chem.  1995,  60:  3020 ; and references therein

18

Water may simply assist the substitution steps, although dissociation of chloride from Pd(PPh₃)₂Cl₂ was not detected by NMR in D₂O in the absence of boron component.