Peter Eilbracht

CC-einfachbindungsspaltung 1,1-dialkylsubstituierter cyclopentadiene durch Fe2(CO)9 unter ausbildung von π-cyclopentadienyl-σ-alkyl-eisen-komplexen

Zusammenfassung Cleavage of Cue5f8C single bonds within tricarbonyliron complexes of 1,1-dialkyl-substituted cyclopentadienes is promoted by Fe 2 (CO) 9 in boiling benzene and leads to π-cyclopentadienyl-σ-alkyldicarbonyliron complexes. According to crossover experiments the endo -alkyl group is intramolecularly transferred from the diene ligand to the metal.

Ring-opening reactions of spiro[2.4]hepta-4,6-diene and spiro[4.4]nona-1,3-diene induced by tungsten(0) carbonyls

Tungsten(0) carbonyls react with the strained spiro[2.4]hepta-4,6-diene and the less strained spiro[4.4]nona-1,3-diene with Cue5f8C bond cleavage and formation of stable alkylene bridged π-cyclopentadienyl-σ-alkyl complexes. The product containing a two carbon bridge has the same unusual spectroscopic properties as the analogous molybdenum complex.

13C-NMR-spektroskopische untersuchung der tricarbonyl(1,2,3,4,5,2′-η-ethylcyclopentadien-1,2′-diyl)- komplexe des molybdäns und wolframs. deformierte σ-alkyl-π-cyclopentadienyl-metall-komplexe

Summary In order to gain further insight in the bond structure of bridged σ-alkyl-π-cyclopentadienyl complexes, obtained from spiro[2.4]hepta-4,6-diene their13C NMR spectra were recorded, analyzed, and compared with those of analogous compounds. It was concluded that the 3-membered ring of the starting hydrocarbon is completely opened and a “homofulvene” structure can be discarded.13C NMR spectra further suggest strong steric deformations in the ethano bridged compounds.

Reactions of 1-vinylspiro[2.4] hepta-4,6-diene with nickel(0) and molybdenum(0) carbonyls

Abstract 1-Vinylspiro[2.4] hepta-4,6-diene reacts both with nickel(0) and molybdenum(0) carbonyls via C—C bond cleavage and CO insertion, forming bridged π-cyclopentadienyl-σ-alkyl and acyl complexes.

Zur bildungsweise von fulvenkomplexen aus spiro[2.4]heptadien und spiro[4.4]nonadien mit Fe2(CO)9

Zusammenfassung Bridged σ-alkyl- and σ-acyl-π-cyclopentadienyldicarbonyliron complexes derived from spiro[4.4]nonadiene and spiro[2.4]heptadiene are transformed to diiron fulvene complexes by Fe 2 (CO) 9 . A reaction path via insertion of a Fe(CO) 4 unit into the iron—carbon bond is postulated and supported by isolation of a corresponding dinuclear alkyI complex.

Conversion of 6,6-dimethylfulvene into 1-isopropenyl-1′-isopropyl-ferrocene by cocondensation with iron vapour

Cocondensation of dimethylfulvene with iron vapour yields solely 1-isopropenyl-1′-isopropylferrocene by intramolecular disproportionation.

Ring-opening reactions of spiro[2.4]hepta-4,6-diene and spiro[4.4]nona-1,3-diene with Co2(CO)8; a facile access to dicarbonyl-η5-vinylcyclopentadienylcobalt

Abstract Spiro[2.4]hepta-4,6-diene and spiro[4.4]nona-1,3-diene both react with Co2(CO)8, and substituted dicarbonyl-η5-cyclopentadienylcobalt complexes are formed by disproportionation, coupling, or recyclisation of the ring-opened intermediates.