Metal carbonyl complexes of the trindenyl ligand: crystal structure of trans-[Re(CO)3]3(trindenyl)

A rhenium carbonyl bonded to highly dealuminated zeolite Y: structure determination by infrared and X-ray absorption spectroscopies

“…71 Some molecular rhenium carbonyls are also characterized by a high-frequency n CO band at relatively high wavenumbers and may be considered as analogues of the zeolite-supported complex (e.g., 2034 cm À1 for [Re(CO) 3 ] 3 Td in THF (Td ¼ a trindenyl trianion containing three conjugated cyclopentadienyl rings). 41,72 [Re(CO) 3 ] 3 Td in THF is characterized by two major n CO bands, at 2034 cm À1 and 2022 cm À1 , which almost exactly match the 2036 cm À1 and 2022 cm À1 bands representing Re(CO) 3 in zeolite DAY 773 . 74 Similarly, ruthenium tricarbonyls bonded to zeolite DAY are also characterized by three n CO bands: 2151 vs, 2091 vs, and 2086 vs cm À1 .…”

“…36 Table 2 is a summary of the IR absorption bands of rhenium carbonyls on various supports 11,15,16,[37][38][39] and in solution. [40][41][42] A rhenium carbonyl bonded to three equivalent surface sites has C 3v symmetry, resulting in a spectrum with two main n CO bands. [11][12][13][15][16][17]43,44 The literature of oxide-supported rhenium carbonyls typically indicates such bands; the surface sites are typically inferred to be O 2À or OH À .…”

“…64 The EXAFS data indicate that the rhenium carbonyl in zeolite DAY 773 is well approximated as Re(CO) 3 bonded to three surface oxygen atoms. The IR spectra of Re(CO) 3 (Table 2) 11,15,16,37,40,41 typically include two or three major n CO bands, which vary in position depending on the support pretreatment conditions (and degree of dehydroxylation). Two n CO bands indicate a rhenium carbonyl on surface sites with three identical surface ligands, and three n CO bands indicate surface sites presenting nonequivalent ligands.…”

“…2) and its similarity to the spectra of molecular metal carbonyls. 41 Thus, we model the supported rhenium carbonyl as a crystallographically unique species. A key issue is where in the zeolite the rhenium carbonyls are bound.…”

Synthesis of the Prototypical Cyclic Metallocene Triad: Mixed‐Valence Properties of [(FeCp)3(trindenyl)] Isomers

“…The use of Td as a metal bridging ligand is particularly favorable because strain is minimal as a consequence of the presence of only five‐ and six‐membered rings. In spite of this, no trimetallocene complexes of Td have been reported11 and only a handful of homo‐ and heterotrimetallic derivatives of [Re(CO) 3 ],12 [Mn(CO) 3 ],12 and [Rh(cod)]13 have been synthesized and studied by cyclic voltammetry (CV) 14…”