Rainer Bartsch

First examples of η5- and η5 η1-coordination in triphosphorus analogues of ferrocene. Crystal structure of the iron sandwich complex [Fe(η5-C5H5) (η5-C2R2P3)W (CO)5] (R But)

Abstract Syntheses of the novel sandwich compounds [Fe(η 5 -C 5 H 5 )(η 5 -C 2 R 2 P 3 )] and [Fe(η 5 -C 5 H 5 )(η 5 -C 2 R 2 P 3 )W(CO) 5 ], (R  Bu t ), are described. The mode of attachment of the [W(CO) 5 ] fragment in the latter compound has been determined by NMR and single crystal X-ray diffraction studies.

Hexa-phosphorus analogues of metallocenes: synthesis of the first paramagnetic sandwich complex containing two η51,2,4-triphosphacyclopentadienyl rings. Crystal and molecular structures of [Cr(η5-C2But2P3)2]

Abstract The first paramagnetic sandwich complex containing η 5 -1,2,4-triphosphacyclopentadienyl rings, has been synthesised, and its molecular structure determined.

Synthesis, crystal and molecular structure of the “slipped” sandwich complex [Ni(η5-P3C2R2)(η3-P2C3R3)] (R = But)

Abstract The synthesis of the novel “slipped” sandwich compound [Ni(η 5 -P 3 C 2 R 2 )(η 3 -P 2 C 3 R 3 )] (R = Bu t ) is described. The mode of attachment of the P 3 C 2 R 2 and P 2 C 3 R 3 rings has been determined by NMR spectroscopy and a single crystal X-ray diffraction study.

Penta- and hexaphospha ferrocenes as ligands : crystal and molecular structures of [Fe(η5-P3C2tBu2)2W(CO)5], [Fe(η5-P3C2tBu2)(η5-P2C3tBu3)W(CO)5] and the novel triruthenium carbonyl cluster complex [Fe(η5-P3C2tBu2)2Ru3(CO)10] containing two interlinked η5-P3C2tBu2 ring systems

Abstract The lone-pair electrons of one of the two directly bonded phosphorus atoms of the P3C2tBu2 ring in the penta- or hexaphosphaferrocene complexes [Fe(η5-P3C2tBu2)(η5-P3C2tBu3)] and [Fe(η5P3 C2tBu2)2] can ligate to other metal centres to afford novel bi- and tetrametallic complexes, whose structures have been elucidated by NMR and single crystal X-ray crystallographic studies.

Syntheses of mixed transition metal clusters containing the coordinated phosphaalkyne tBuCP

Abstract Syntheses of the phosphaalkyne complexes [Ni2(η5-C5H5)2(tBuCP)] and [CoNi(η5-C5H5)(CO)3(tBuCP)] are described. Adducts of the latter with [W(CO)5] and [Mn(CO)2(η5-C5H5)] are also reported. The reactions of tBuCP with [CoMn(CO)9] or [RuCo2(CO)11] lead to the disproportionation products [Co2(CO)6(tBuCP)] and [Mn2(CO)10] or [Ru3(CO)10], respectively.

Novel synthesis of di- and tri-phosphollide ions and their ferrocene analogues

Abstract The preration of di- and tri-phosphollide ions P 3 C 2 R − 2 , P 3 C 2 RR′ − , P 2 C 3 R 2 R′ − , P 2 C 3 RR′ − , P 2 C′ 3 R′ 3 (R = i Pr) and their pentaphospha-ferrocene analogues are described.

Use of coordinated phosphaalkyne ligands in transition metal cluster interlinkage. Synthesis of dimolybdenum-triruthenium and dimolybdenum-triosmium complexes [Mo2M3(η5-C5H5)2(CO)15(tBuCP)], (M = Ru, Os) and crystal and molecular structure of di-η5-cyclopentadienyltetracarbonyl-μ-(3,3-dimethyl-1-phosphabutyne)-triangulo-triosmium(O), [Mo2(η5-C5H5)2(CO)4(μ-tBuCP)Os3(CO)11]

Abstract The phosphaalkyne ligand in [Mo 2 (η-C 5 H 5 ) 2 (CO) 4 ( t BuCP)] can be used in transition metal cluster interlinkage.

Use of Phospha-Alkynes RC[dbnd]P in Organometallic Chemistry

Abstract Novel reactions of phospha-alkynes are described. Phospha-alkynes, RC[dbnd]P, are proving to be important building blocks in inorganic and organometallic chemistry. A variety of ligating modes are exhibited by RC[dbnd]P towards transition metal centres but, interestingly, the preferred bonding interaction is with the P[dbnd]C triple bond, rather than via the phosphorus lone-pair electrons. Previously,1,2 we have shown that n1-phospha-alkyne complexes of Mo(0) and Fe(II) can be synthesised in certain compounds, in which linear molecules can approach the metal centre by virtue of the constraints imposed by the attendant diphosphane ligands.

A study of the molecular and electronic structure of iron(II)and ruthenium(II) 1,3-di- and 1,2,4-tri-phospholyl sandwich compoundsby photoelectron spectroscopy and density functional theory

The synthesis and variable temperature 1H NMR spectrum of the new tetraphosphaferrocene [Fe(η5-P2C3Bu3t)2] are presented and the photoelectron spectra are reported for [Fe(η5-P3C2Bu2t)2] 1a, [Fe(η5-P2C3Bu3t)2] 2a, [Fe(η5-P2C3Bu3t)(η5-P3C2Bu2t)] 3a and [Ru(η5-P3C2Bu3t)2] 4a. Density functional calculations were used to optimise the geometry and calculate the ionization energies of the parent analogues. Good agreement was obtained with the experimental results, giving support to the theoretical modelling of these sandwich compounds. Analysis of their electronic structure showed that replacement of RC fragments by P atoms in the η5-ligated cyclopentadienyl rings increases their acceptor properties. Extensive σπ mixing makes the description of the orbitals complex. Some higher lying Pσ levels are found to have similar ionization energies to the d electrons.

Sulphurisation reactions of P5C5tBu5 and P5C5tBu5H2: crystal and molecular structure of the ethanol adduct of P5C5tBu5H2S3

Abstract Treatment of P 5 C 5 t Bu 5 , and P 5 C 5 t Bu 5 H 2 with an excess of sulphur affords the corresponding mono- and trisulphur compounds P 5 C 5 t BuS and P 5 C 5 t BuH 2 S 3 , respectively, whose structures have been elucidated by NMR spectroscopy; and in the case of the trisulphur derivative confirmed by a single crystal X-ray study of its EtOH adduct, P 5 C 5 t Bu 5 H 3 S 3 (OEt).