Phosphane-free Suzuki-Miyaura coupling of aryl imidazolesulfonates with arylboronic acids and potassium aryltrifluoroborates under aqueous conditions

Aryl imidazole-1-sulfonates are efficiently cross-coupled with arylboronic acids and potassium aryltrifluoroborates using only 0.5 mol % of oxime palladacycles 1 under aqueous conditions at 110 °C. Under these simple phosphane-free reaction conditions a wide array of biaryl derivatives has been prepared in high yields. This methodology allows in situ phenol sulfonation and one-pot Suzuki arylation as well as the employment of microwave irradiation conditions.

Financial support from the MICINN (Projects CTQ2007-62771/BQU, CTQ2010-20387, and Consolider INGENIO 2010 CSD2007-00006), FEDER, the Generalitat Valenciana (Projects GV/2007/142 and PROMETEO/2009/038), and the University of Alicante is acknowledged. M. G. thanks Shiraz University and University of Alicante for grants.