Ag[Fe(CO) 5 ] 2 + : A Bare Silver Complex with Fe(CO) 5 as a Ligand

Attempts to prepare Fe(CO) 5 + from Ag[Al(OR F ) 4 ] (R F =C(CF 3 ) 3 ) and Fe(CO) 5 in CH 2 Cl 2 yielded the first complex of a neutral metal carbonyl bound to a simple metal cation. The Ag[Fe(CO) 5 ] 2 + cation consists of two Fe(CO) 5 molecules coordinating Ag + in an almost linear fashion. The ν(CO) modes are blue‐shifted compared to Fe(CO) 5 , with one band above 2143 cm −1 indicating that back‐bonding is heavily decreased in the Ag[Fe(CO) 5 ] 2 + cation.