PROTONATION OF AN YLIDE LEADS TO A UNIQUE C-H-CENTER-DOT-CENTER-DOT-CENTER-DOT-O HYDROGEN-BONDED DIMER - THE FIRST SYNTHESIS, ISOLATION ANDX-RAY STRUCTURAL CHARACTERIZATION OF A PHOSPHONIUM ARYLOXIDE

The phosphonium ylide triphenylphosphonium methylide Ph(3)PCH(2) react s with 2,4,6-trimethylphenol to give the phosphonium aryloxide dimer [ (Ph(3)PMe)(+)(OC(6)H(2)Me(3)-2,4,6)(-)](2) 1, in the solid state, in w hich aggregation is solely through C-H ... O hydrogen bonding from bot h alkyl and aryl donors within the phosphonium cation, resulting in ea ch phenoxide oxygen acceptor being five-coordinate (tetrafurcated).