Shahid A. Kazi, E. Campi, M. Hearn
Apr 12, 2018
Citations
1
Influential Citations
11
Citations
Journal
Tetrahedron
Abstract
Abstract A synthetic procedure has been developed to enable the sequential regio-selective Suzuki-Miyaura cross-coupling of 1,4-dibromo-2-nitrobenzene with a variety of arylboronic acids. The first Suzuki coupling step, using a phosphine-free palladium catalyst at room temperature, gave selective coupling at the position ortho to the nitro group, opening a convenient synthetic route to unsymmetrical para-terphenyls. The bromobiaryl product was then subjected directly to the second coupling step, in situ, using preferred aryl-boronic acids to give by this one-pot batch procedure unsymmetrically substituted para-terphenyls in excellent overall isolated yields. This methodology should be particularly suited for the generation of targeted chemical libraries, as well as for the synthesis of precursors of biologically active compounds or natural products which are derived from the unsymmetrical para-terphenyl core.