1267964-51-1Relevant articles and documents
Regioselectivity in the aryne cross-coupling of aryllithiums with functionalized 1,2-dibromobenzenes
Diemer, Vincent,Begaud, Manon,Leroux, Frederic R.,Colobert, Fracoise
experimental part, p. 341 - 354 (2011/02/28)
Tri- and tetrasubstituted ortho-bromobiaryls have been synthesized in good-to-excellent yields by aryne cross-coupling reactions starting from 1,3-dimethoxybenzene and functionalized 1,2-dibromobenzenes. This study outlines the influence of the 1,2-dibromobenzene precursor as well as the reaction temperature on the outcome of the aryl-aryl bond formation and indicates, in the case of dissymmetrical benzyne precursors, how structural parameters (electronic effects, steric hindrance, temperature, etc.) control the regioselectivity of the aryne cross-coupling reactions. A wide range of o,o′-tri- and-tetrasubstituted biphenyls have been prepared by a transition-metal-free "aryne" cross-coupling starting from 2,6-dimethoxyphenyllithium and various functionalized 1,2-dibromobenzenes. Mechanistic investigations outline the key parameters that govern both the aryl-aryl bond formation and the regioselectivity of the reaction with dissymmetrical aryne precursors. Copyright
