V.N. Postnov

The behaviour of 2-methylene-3-ferrocenylmethylenecamphane under conditions leading to the cyclodimerization of ferrocenyl-1,3-butadienes

The behaviour of 2-methylene-3-ferrocenylmethylenecamphane under proton cyclodimerization conditions has been investigated. The stage involving the formation of the dimeric linear allylic cation has been confirmed in these interactions by isolating of corresponding diene. Its structure has been established unambiguously by X-ray methods. All substances isolated have been characterized by elemental analyses and 1H and 13C NMR spectral data.

Fragmentation reactions of 1,3,5-triferrocenyl-4-(1-ferrocenylvinyl)-, 1-aryl-4-(1-arylvinyl)-3,5-diferrocenyl-, and 3,5-diaryl-1-ferrocenyl-4-(1-ferrocenylvinyl) cyclohexenes

Abstract Monocyclic ferrocenylsubstituted terpenoids, produced upon proton-induced cyclodimerization of ferrocenyl-1,3-dienes, undergo fragmentation under the action of electrophilic agents (HBF 4 , [PhCHFc]BF 4 , or [MeOC 6 H 4 CHCHCHC 6 H 4 OMe]BF 4 ) to give two molecules of methyl-, (2-ferrocenyl-2-phenylethyl)-, or 2,4-bis(p-methoxyphenyl)-3-butenyl-ferrocenylallylium tetrafluoroborates. Treatment of these salts with dimethylaniline yields, depending on their structure, the starting cyclodimers, seven-membered cyclic compounds, dimethylaniline alkylation products, or tricyclic compounds.

Asymmetric induction in the synthesis of metallocenylpyrazolines

The asymmetric induction in the synthesis of pyrazolines with ferrocenyl and phenylbutadienyliron tricarbonyl substituents is estimated. Diastereomeric selectivity is shown to be sufficiently high both by the induction of a chiral centre by a chirality plane and vice versa. The molecular geometry of diastereomeric 1-acetyl-3-[4-phenylbutadienyliron tricarbonyl]-5-ferrocenylpyrazolines is discussed.

Mass spectrometry of γ-Complexes of transition metals : XXII. Fragmentations of ferrocenyl-substituted pyrazolines-2 under electron impact

Abstract The mass spectra of 1- N -acetyl- and 1- N -phenyl-3-ferrocenyl-5-arylpyrazolines-2, their 5-ferrocenyl-3-aryl isomers and their 3,5-diferrocenyl analogues have been studied. The “pyrazoline” type of the molecular ion fragmentation involves various processes of heterocyclic nucleus destruction and elimination of the substituents or their fragments. The directions and intensifies of the processes observed are interpreted in terms of preferred positive charge localization on the transition metal atom. Interactions between the acetyl and ferrocenyl groups manifest themselves by the appearance of intense [P  C 5 H 5 ] + ions (ferrocenyl type fragmentation products) in the mass spectra of 1- N -acetyl-3-aryl-5-ferrocenylpyrazolines-2 only. The fragmentation mechanism leading from [ P  C 5 H 5 ] + to C 7 H 7 OFe + is discussed.

Cyclopropanes with a ferrocenyl group

Abstract 1-Ferrocenyl-2-arylcyclopropanes have been synthesized by catalytic thermolysis of ferrocenylpyrazolines. An X-ray diffraction study of trans-1-ferrocenyl-2-p-methoxyphenylcyclopropane isolated in an individual form was carried out.

Interaction of CH3MgI with β-dicarbonyl compounds

Abstract The reaction of CH3MgI with the ferrocene-containing α-monosubstituted β-dicarbonyl compounds is studied; a general reaction scheme is proposed. The addition reaction to a carbonyl group, the enolization and the CαCβ-cleavage prove to be non-specific by D-labelling.

Reaction of CαCβ-cleavage in the series of monosubstituted β-dicarbonyl compounds

Abstract Interaction of PhMgBr with α-monosubstituted β-dicarbonyl compounds, β-diketones, β-ketonic esters and β-diesters, is studied. A new reaction route, C α C β -cleavage, the course of which is determined by the p K R + value of the α-substituent and the p K a value of the corresponding proton analog of the β-substituent is found.

On the stereochemistry of pyrazolines: 1-Acetyl-3,5-disubstituted pyrazolines-2

Abstract The geometries of the molecules of the isomeric N -acetyl derivatives of 3-ferrocenyl-5- p -bromophenyl- and 3- p -bromophenyl-5-ferrocenylpyrazolines-2 with a chiral centre in position 5 of pyrazoline have been determined by an X-ray study.

Intermolecular hydrogen bonding in β-hydroxycarbonyl ferrocene compounds

Conclusions1.IR and PMR spectroscopy was used to study the different types of hydrogen bonds formed in solutions of β-hydrocarbonyl ferrocene compounds. The observed spectral behavior can be explained by the formation on an intramolecular hydrogen bond of the OH group with the iron atom only in the case of a dilute solution of the ethyl ester of 3-hydroy-2-(phenylferrocenylmethyl)-3-methylbutanoic acid.2.Only OH⋯OH− and OH⋯O=C interactions were found for this isomer in the crystalline state.