Synthesis and cyclic voltammetry of some new metal carbene substituted cyclopentadienyliron half sandwich complexes

Recent advances in the field of multicarbene and multimetal carbene complexes of the Fischer-type

“…31). In all cases, only one reduction and only one oxidation were observed (so that both metal atoms participate in one molecular orbital) although there are two redox active metal atoms in the molecule [139]. This was in direct contrast to the recent electrochemical results obtained where heterodimetallic carbene complexes with a π-aryl metal carbene substituent showed that the two metal moieties in each complex function as separate, localized redox centres [140].…”

“…37) [11,158], the tethered biscarbene complexes (95) in Fig. 37 are two of the scarce examples with two cyclopentadienylcarbene moieties [139]. ( Fig.…”

New metal aminocarbene-substituted cyclopentadienyliron half sandwich complexes

“…This contrasts the structure of 3, in which the cyclopentadienyl system and the carbene complex moiety are more or less coplanar [23]. In addition, the configuration of the carbene carbon-nitrogen bond is Z as revealed from the dihedral angle C7-N1-C1-W1 [À8(2)°].…”

“…Prior to our work only one half sandwich cyclopentadienylcarbene complex [20] and a related thiophene complex had been reported [21]. Some bimetallic half sandwich iron cyclopentadienyl alkoxycarbene complexes were reported by our group [22,23], and these complexes showed interesting structural and electrochemical behavior. Half sandwich cyclopentadienyl aminocarbene complexes have so far not been reported.…”

“…Here, ethoxycarbene complexes 3-5 served as starting materials [22,23]. Generally, the solutions of the ethoxycarbene complex and of the amine in THF were mixed at À78°C and stirred for 1.5 h. After warming to 25°C over 1 h the product was isolated chromatographically at silica gel.…”