Steric congestion in a cyclopentadienyl ligand bearing tert-butyl groups on three contiguous carbon atoms: crystal and molecular structure of (.eta.5-1,2,3-tri-tert-butylcyclopentadienyl)(.eta.5-indenyl)rhodium(III) hexafluorophosphate

Rhodocenium Complexes Bearing the 1,2,3-Tri-tert-butylcyclopentadienyl Ligand: Redox-Promoted Synthesis and Mechanistic, Structural and Computational Investigations

“…The bond angles (C(7)−C(6)−C(11) and C(7)−C(8)-C(19)) involving the lateral tert -butyl substituents are significantly larger than the analogous bond angles (C(16)−C(7)−C(6) and C(16)−C(7)−C(8)) encompassing the central tert -butyl group. These observations are in agreement with the results of the previously reported crystal structure of 5a + 4b…”

“…Hughes and co-workers recently reported the first example of a complex bearing the novel 1,2,3-tri- tert -butylcyclopentadienyl ligand . The crystallographically characterized 4b rhodocenium complex 5a + (Scheme ) was synthesized by a metal-promoted ring-expansion reaction of tri- tert -butylvinylcyclopropene 1a .…”

Metallocenium Chemistry and Its Emerging Impact on Synthetic Macromolecular Chemistry

“…Another substituted rhodocenium derivative reported in the literature is the (η 5 -1,2,3-tri-tert-butylcyclopentadienyl)(η 5 -indenyl)rhodium(III) cation reported by Donovan-Merkert et al 93 As shown in Figure 43…”

Facile, Redox-Promoted Formation of Rhodocenium Complexes Bearing the 1,2,3-Tri-tert-butylcyclopentadienyl Ligand

“…As shown in Scheme , indenyl derivative 6a reacts in a two-step process to afford 7a + , the only complex bearing the 1,2,3- t Bu 3 Cp ligand reported to date . Chloride-bridged dimer 5 , however, produces η 4 -cyclopentadiene complex 8 on prolonged standing in methylene chloride solution .…”

“…The transition-metal-promoted reactions of 3-vinyl-1-cyclopropenes are of synthetic use and mechanistic interest . Products of these reactions include complexes containing substituted η 4 -cyclopentadiene or η 5 -cyclopentadienyl ligands, − free cyclopentadienes, 1,2,3,5-η- or 1,5-η-pentadienediyl complexes, 2,4,5,7,8 and, after incorporation of CO, phenols and cyclohexadienones. 4,9,10 These transformations are relevant to the synthetically useful Dötz reaction in which five- and six-membered organic rings are produced by treating Fischer carbenes with alkynes. , The production of complexes containing substituted η 5 -cyclopentadienyl ligands is illustrated by the reaction of 1,2,3-triphenyl-3-vinyl-1-cyclopropene ( 1 ) (Scheme ) with Rh(I) to generate complexes 3a , b …”