The site-selective functionalization of halogen-bearing phenols: an exercise in diversity-oriented organometallic synthesis

The organometallic approach to diversity-oriented org. synthesis was subjected to a further test, this time in the phenol series. The model compds. selected were 2,3,6-trifluorophenol, the three isomers of (trifluoromethoxy)phenol and the three isomers of chlorophenol. A combination of optionally site selective metalations and protective group-controlled metalations enabled the selective generation of several isomeric intermediates in each case and their subsequent conversion into functionalized derivs., in particular hydroxybenzoic acids. [on SciFinder (R)]