A Polymer-Supported Phosphazine as a Stable and Practical Reagent in the Three-Component Synthesis of Substituted (Cyclopentadienyl)tricarbonylrhenium Complexes

A very stable heterogenized difunctional cyclopentadienyl-ring precursor , storable under ambient conditions, readily participates in the simultaneous formation of a η⁵ bond with a [fac-Re(CO)₃]⁺ species and a σ bond with heteroatom (halides, carboxylates) or carbon nucleophiles (boronic acids) to produce halo-, acyloxy-, or carbon-substituted cyclopentadienyl–Re(CO)₃ complexes in a one-pot reaction in yields of between 41 and 71 % [Eq. (1)]. No catalyst is required and unprotected (usually) sensitive functional groups are well tolerated.