Decasubstituted decaphenylmetallocenes

Abstract

Pentaphenylcyclopentadienes that are para-substituted at each phenyl group prove to be valuable new ligands. They are easily prepared in good yield and high purity from pentaphenylcyclopentadiene by acetylation and subsequent acetalation. Owing to the ease with which the electronic properties of these ligands can be modified and due to the solubility and the facile characterization of their complexes it is now possible to explore the whole field of decaatylmetallocenes. The first soluble decaaryhnetallocenes with tin and lead as the metal atom are described.

Insight in cyclopentadienyl metal complexes with superbulky ligands: The crystal structure of [CpBIGK]∞

“…The ligand (4-nBu-C 6 H 4 ) 5 Cp, which we abbreviate as Cp BIG , gave access to various sandwich complexes (1-Ca, 1-Sr, 1-Ba, 1-Yb and 1-Sm) which are well-soluble in hexane at room temperature [7,8]. All complexes crystallize from this solvent isomorphously and their crystal structures show surprisingly ordered nBusubstituents.…”

“…These problems have been circumvented by slight modification of the ligand: substituents in the aryl ring greatly increase the solubility of the organometallic complexes [5][6][7][8]. Also, modification of the synthetic procedures gave access to single crystals of (Ph 5 Cp) 2 Ca, (Ph 5 Cp) 2 Ba and (Ph 5 Cp) 2 Yb [9].…”

“…Although the sterically congested cyclopentadienyl (Cp) ligand Ph 5 CpH is one of the cheapest commercially available substituted Cp ligands, its organometallic chemistry has hardly been developed [1]. Until recently, only few metallocene complexes (Ph 5 Cp) 2 M have been structurally characterized (M = Sn [2], Fe [3]) and a handful of structures for ionic metallocenes [(Ph 5 Cp) 2 M + ][X À ] were known [4].…”

Remarkable Stability of Metallocenes with Superbulky Ligands: Spontaneous Reduction of SmIII to SmII

“…Complexes containing the Ph 5 C 5 ligand are very insoluble on account of their rigidity and high symmetry. [1] Therefore, we used the modified perarylated cyclopentadiene (4-nBu-C 6 H 4 ) 5 C 5 H (Cp BIG H), which can be obtained in a simple highyield, one-pot procedure. [10] This ligand can be smoothly deprotonated by [(4-tBu-benzyl) 2 (thf) 4 Ca] in benzene at 60 8C (Scheme 1).…”

Piano stool complexes containing the bulky pentaphenylcyclopentadienyl(C5Ph5) ligand: Preparation, characterization and X-ray structure of C5Ph5Zr(N(CH3)2)3 (I)

“…Complex I is of interest as it is one of few structurally characterized group 4 complexes with the pentaphenylcyclopentadienyl ligand [16,1] whereas later transition metal complexes of this ligand have been more extensively studied [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34]. In addition, the structural data suggest an agostic interaction with one of the amido methyl groups.…”