Oxotrichlorobis(triphenylphosphine)rhenium(V) is the chemical compound with the formula ReOCl₃(PPh₃)₂. This yellow, air-stable solid solid is is a precursor to a variety of other rhenium complexes. In this diamagnetic compound, Re has an octahedral coordination environment with one oxo, three chloro and two mutually trans triphenylphosphine ligands. The oxidation state of rhenium is +5 and its configuration is d².

Synthesis

ReOCl₃(PPh₃)₂ is commercially available, but it is readily synthesized by reaction of perrhenic acid with triphenylphosphine in a mixture of hydrochloric acid and acetic acid. In this reaction, Re(VII) is reduced to Re(V), and triphenylphosphine is oxidized to its oxide.

HReO₄ + 3 HCl + 3 PPh₃ → ReOCl₃(PPh₃)₂ + Ph₃PO + 2 H₂O

The required perrhenic acid solution can be prepared in situ from rhenium(VII) oxide.

Uses

ReOCl₃(PPh₃)₂ is a precursor to a variety of other oxo-, nitridio, and hydrido complexes. It converts to ReH₇(PPh₃)₂ by a treatment with LiAlH₄.

ReOCl₃(PPh₃)₂ catalyzes the selective oxidation of secondary alcohols by DMSO, producing the corresponding ketals.

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