87556-65-8Relevant academic research and scientific papers
Preparation and reactivity of (μ-hydrido)(μ-phenylacetylido)dirhenium octacarbonyl, (μ-H)(μ-C≡CPh)Re2(CO)8
Nubel, Philip O.,Brown, Theodore L.
, p. 29 - 32 (2008/10/08)
(μ-Hydrido)(μ-phenylacetylido)dirhenium octacarbonyl, I, is prepared by the room-temperature reaction of phenylacetylene with (μ-hydrido)(μ-propenyl)dirhenium octacarbonyl. I undergoes remarkably facile CO substitution by pyridine, triphenylphosphine, or triisobutylphosphine. Kinetics results for the reaction with pyridine are consistent with a CO dissociative mechanism; the first-order rate constant at 26°C is 4.9 × 10-4 s-1. Structures for the mono- and disubstituted derivatives of I are proposed on the basis of IR data. The bridging acetylide ligand of I and its derivatives undergoes a rapid fluxional process at 20° C in which the σ and π bonds are interchanged between the bridged rhenium atoms. Treatment of I with trimethylphosphine rapidly generates a dipolar addition product via nucleophilic attack of PMe3 at the μ-acetylide ligand. This reactivity is not observed with the larger phosphines, PPh3 and P(i-Bu)3.
