Solid-state organometallic chemistry of molecular metal oxide clusters: C―H activation by an iridium polyoxometalate

Hydrogenation of ((Ph/sub 3/P)/sub 2/Ir(C/sub 8/H/sub 12/))/sub 3/PW/sub 12/O/sub 40/ in a solid-gas reaction produces ((Ph/sub 3/P)/sub 2/IrH/sub 2/)/sub 3/PW/sub 12/O/sub 40/. EXAFS studies of the molybdenum analogue indicate the presence of isolated, lattice-stabilized (Ph/sub 3/P)/sub 2/IrH/sub 2//sup +/ ions. H/emdash/D exchange with CD/sub 3/CH/double bond/CH/sub 2/ occurs via a reversible C/emdash/H addition reaction that also produces ((Ph/sub 3/P)/sub 2/IrH(/pi/-C/sub 3/H/sub 5/))/sub 3/PW/sub 12/O/sub 40/ and scrambles the C/sub 3/D/sub 3/H/sub 3/ deuterium label. Exchange with toluene is selective and involves activation of aromatic but not aliphatic C-H bonds. Slow exchange with c-C/sub 6/D/sub 12/ also occurs.