Irreversible Hydrolysis of PCP-Supported Rhenium(V) Acetates

Complexes (PCPR)Re(O)(OAc)2 [R = iPr (4a) and tBu (4b); PCP = κ3-P,C,P-2,6-(R2PCH2)2C6H3] undergo unexpected irreversible hydrolysis to yield (PCPR)Re(O)(OAc)(OH) (3a/3b) and free AcOH. 3a and 3b are highly fluxional in solution, possibly via AcOH loss and the intermediacy of (PCPR)Re(O)2, which was isolated for R = tBu (5b).