[(C5Me4R)Co(As2)]-Molekülbausteine

Open Chain Polyarsenides of the Lanthanides

“…The analogous arsenic species [(Cp'''Co) 2 (m,h 2:2 -As 2 ) 2 ]h as recently been synthesized by the reaction of As 4 with [{Cp'''Co} 2 {m,h 4:4 -toluene}] [21] representing a triple decker complex with two As 2 units as am iddle deck. This compound is similar to the earlier described species [((C 5 Me 4 R)Co) 2 (m,h 2:2 -As 2 ) 2 ]( R = Me, Et) [22] but different to the cation [(Cp tBu Co) 2 As 4 ] 2 + ,w hich possesses as quare planar arranged As 4 ring in the centre. [23] Herein, we show that the proposed strategy can be transferred to the heavier congener arsenic for the synthesis of a series of unique complexes containing an As 4 chain as the ligand in the coordination sphere of f-block elementc omplexes.…”

“…The analogous arsenic species [(Cp′′′Co) 2 ( μ,η 2 :2 ‐As 2 ) 2 ] has recently been synthesized by the reaction of As 4 with [{Cp′′′Co} 2 {μ,η 4:4 ‐toluene}] representing a triple decker complex with two As 2 units as a middle deck. This compound is similar to the earlier described species [((C 5 Me 4 R)Co) 2 ( μ,η 2 :2 ‐As 2 ) 2 ] (R=Me, Et) but different to the cation [(Cp t Bu Co) 2 As 4 ] 2+ , which possesses a square planar arranged As 4 ring in the centre …”

“…IR spectra were obtained on a Bruker Tensor 37 FTIR spectrometer equipped with a room temperature DLaTGS detector and a diamond ATR (attenuated total reflection) unit; for the mid‐infrared region, a KBr beamsplitter was used. [(Cp′′′Co) 2 ( μ,η 2:2 ‐As 2 ) 2 ], [Cp* 2 Sm(THF) 2 ], [Cp* 2 Sm] and [(C 5 Me 4 n Pr) 2 Sm] were prepared according to literature procedures.…”

Arsenic‐Rich Polyarsenides Stabilized by Cp*Fe Fragments

“…[12] An outstanding example is the synthesis of [PBu 4 ] 3 [As@Ni 12 @As 20 ], which contains an icosahedral [Ni 12 (m 12 -As)] 3À core incorporated into af ullerenelike As 20 cage. [12d] In 1988, Haushalter and co-workers reported on [Rb(crypt)] 4 [As 22 ]·dmf (dmf = dimethylformamide,c rypt = 4,7,13,16,21,24-hexaoxa-1,10-diazatricyclo- [8.8.8]hexacosane), which is,t ot he best of our knowledge, the largest polyarsenide that has been reported thus far. [12b] Apart from the use of Zintl ions as starting materials,w hich usually led to charged polyarsenides,only few neutral arseniccontaining complexes could be obtained starting from yellow Scheme 1.…”

“…As the (As 2 ) 2 units are severely disordered, the bonding parameters cannot be discussed in detail. [15] Additionally,t he central (As 2 ) 2 ligands can be compared with neutral complexes of the general formulae [{Cp R Co(m,h 2:2 -As 2 )} 2 ]( Cp R = Cp*, [22] Cp + (h 5 -C 5 EtMe 4 ), [22] Cp''' [14] ). [15] Additionally,t he central (As 2 ) 2 ligands can be compared with neutral complexes of the general formulae [{Cp R Co(m,h 2:2 -As 2 )} 2 ]( Cp R = Cp*, [22] Cp + (h 5 -C 5 EtMe 4 ), [22] Cp''' [14] ).…”