Bis(alkylcyclopentadienyl)cadmium Complexes and Alkylcyclopentadienyl(mesityl)cadmium:  Synthesis and Structure

Abstract

Cadmium diiodide tetrahydrofuran adduct was prepared from the elements in tetrahydrofuran and converted to bis(alkylcyclopentadienyl)cadmium complexes with sodium tetraisopropylcyclopentadienide or sodium 1,2,4-tri(tert-butyl)cyclopentadienide. Both products are fluxional in solution, and for bis{tri(tert-butyl)cyclopentadienyl}cadmium η1,η1-bonding has been observed in the solid state. With 1 equiv each of sodium 1,2,4-tri(tert-butyl)cyclopentadienide and mesitylmagnesium bromide the aryl complex mesityl{tri(tert-butyl)cyclopentadienyl}cadmium could be obtained from cadmium diiodide in moderate yield.

Amido analogues of zincocenes and cadmocenes

“…In contrast, in 2 the two carbazol-9-yl ligands lie parallel, but are rotated 180 • away from each other with the Cd-N bond lying approximately perpendicular to the plane of the carbazol-9yl ligand [101.6(5), 97.9(5) • ] in a similar configuration to that for (1,2,4-t Bu 3 C 5 H 2 ) 2 Cd (92.5 • ). 28 The bonding between the t Bu 4 carb ligands and the Cd centre in 2 is in sharp contrast to that for the complexes (1,8-Ph 2 -3,6-Me 2 C 12 H 4 N) 2 M (M = Mn, Fe), 12 in which the M-N bonds are almost coincident with the least squares planes of the carbazol-9-yl ligands. The central nitrogen-containing ring in 1 deviates from planarity, leading to significant puckering of the t Bu 4 carbligands, which is much less pronounced in 2.…”

Coupling Reactions of Functionalized Zintl Ions [E9Cd(C6H5)]3− (E = Sn, Pb) with Tributyltinhydride: Synthesis and Isolation of {Sn9CdSn[(CH2)3CH3]3}3−

“…This bonding analysis implies that the reported closo -[E 9 Cd(C 6 H 5 )] 3− clusters are isoelectronic with the hypothetical species (η 5 -Cp)CdPh, which has yet to be isolated because of the relative instability of such organometallic complexes. The dearth of structurally characterized base-free cyclopentadienyl- or alkylcyclopentadienyl-cadmium organometallics is largely due to the high air-, moisture-, and light-sensitivity of such complexes . However, such an absence may also be attributed to the greater main-group character of the cadmium metal center, which makes base-free closed-shell organometallic complexes exhibiting an 18-electron count highly unusual .…”

Investigation into the molecular structure and energetic stability of endohedral and exohedral metallofullerene derivatives of C24

“…In fact, the Hg‐C bonds in phenylcyanamide and phenylmercury complexes are approximately 0.2 Å shorter than what we report for the +2:3 Hg‐C 24 derivative. The bond lengths for Cd‐C for cadmium‐cyclopentadienyl complexes are approximately 2.3 Å and the Zn‐C 24 bond lengths are slightly longer than that reported for Zn‐carbon distances in multidentate N‐heterocyclic carbene complexes and El Mahdy's Zn‐C 60 bond lengths . Charra et al also report that Cu‐C bond lengths are approximately 0.1 Å shorter in the multidentate N‐heterocylic complexes in comparison to the Cu‐C 24 , whereas the Ag‐C 24 bond lengths are comparable to the Ag‐C distances reported for CAg n clusters .…”