Studies in the tetraarylborates

Abstract The stability of sodium tetraarylborates toward acid attack can be enhanced by placing electron-withdrawing substituents at the m - or p -positions of the phenyl rings, thus rendering them less susceptible to electrophilic attack. A series of tetraarylborates has been studied, and the following order of decreasing resistance toward acid attack has been established: m -fluorophenyl > p -trifluoromethylphenyl > m -trifluoromethylphenyl > p -fluorophenyl ≧ p -chlorophenyl ⋍ phenyl > p -methylphenyl > p -methoxyphenyl. Sodium tetrakis ( m -fluorophenyl) borate does not undergo acid decomposition at pH 2.0 and 50.0°, but it is partially decomposed under these conditions via other pathways.