Wolf Peter Fehlhammer

Isonitrilsynthesen am Komplex VII. HX-Eliminierungen AUS carbenkomplexen des typs LnM–C(X)NHR. ZUR Umwandlung von Aryl-In Alkylisocyanidliganden über carbenzwischenstufen

Abstract Reaction conditions for the conversion into isocyanide complexes of the carbenes species Cr(CO) 5 {C(NHC 6 H 5 ) 2 } and [Fe(η-C 5 H 5 ) (CO) 2 {C(NHR)NHR′}]- [PF 6 ] (R = R′ = C 6 H 5 , C 6 H 11 ; R = C 6 H 5 , R′ = CH 3 , i-C 3 H 7 , C 3 H 5 (allyl) ,t-C 4 H 9 , C 6 H 11 ) are established. [Fe(η-C 5 H 5 )(CO) 2 CNC 6 H 5 ][PF 6 ] and [Fe(η-C 5 H 5 )- (CO) 2 CNR′][PF 6 ] (R′= i-C 3 H 7 , C 6 H 11 ), respectively, are formed from the asymmetrically substituted diaminocarbeneiron compounds depending on the nature of the alkyl group. Thus, isocyanide ligands can be transformed into each other at the complex, i.e., without breaking the metal to carbon bond. PtCl 2 {C(OC 2 H 5 )NHC 6 H 5 }P(C 2 H 5 ) 3 is converted into either PtCl 2 (CO)P- (C 2 H 5 ) 3 (with COCl 2 /N(C 2 H 5 ) 3 ) or PtCl 2 (CNC 6 H 5 )P(C 2 H 5 ) 3 (with AlCl 3 /N- (C 2 H 5 ) 3 ).

Isonitrilsynthesen am komplex: VI. Reaktionen von addukten unsymmetrischer carbodiimide an η-cyclopentadienyl(dicarbonyl)ferrat(O). ein einfacher weg zu metallkomplexen mit zwei verschiedenen isocyanidliganden

Abstract The unsymmetrical carbodiimides C 6 H 5 NCNR (R = i-C 3 H 7 , t-C 4 H 9 ) add across the FeC(O) bond in [Fe(η-C 5 H 5 )(CO) 2 ] − to afford [2 + 2] cyclic adducts which, upon reaction with protic acids give the diaminocarbene complexes [Fe(η-C 5 H 5 )(CO) 2 {C(NHR)NHC 6 H 5 }]X (X = Cl, [PF 6 ]. With phosgen in the place of H + , formation in one step of the chiral diisocyanide complexes [Fe(η-C 5 H 5 )(CO)(CNR)CNC 6 H 5 ]X is achieved. Oxidation with Ag[PF 6 ] of [(η-C 5 H 5 )(CO) Fe(CO)N(C 6 H 5 )(C NC 6 H 5 )] − yields [Fe(η-C 5 H 5 )(CO) 2 ] 2 and free C(NC 6 H 5 ) 2 , whereas carbodiimide in excess gives rise to the isocyanide bridged dinuclear species [Fe 2 (η-C 5 H 5 ) 2 (CO) n (CNC 6 H 5 ) 4− n ] ( n = 2, 3).

Isocyanide and heteroallene bridged metal complexes: IV. Reactions of carbon disulfide iron, palladium and plantinum complexes with electrophiles. Evidence for a η2-CS2H ligand

Abstract S -Alkylation of [M(η 2 -CS 2 )(PPh 3 )] 2 (M = Pd, Pt) is achieved using stoichiometric amounts of the ‘hard’ alkylating agents [Et 3 O][BF 4 ] and CF 3 SO 2 OMe, while MeI or 1,2-diiodoethane give [(Ph 3 P) 2 (I)Pt(μ-CS 2 )Pt(PPh 3 ) 2 ]I and [(Ph 3 P) 2 (I)Pt(μ-CS 2 )Pt(I)PPh 3 ], respectively. Protonation of [Fe(η 2 -CS 2 )(CO) 2 L 2 ] (L = PMe 2 Ph, PPh 3 ) affords extremely labile complexes containing the novel η 2 -CS 2 H ligand. The first cationic η 2 : η 1 -CS 2 bridged dinuclear complexes [L 2 (OC) 2 Fe(SCS)Pt(Cl)-(PPh 3 ) 2 [BF 4 ] (L = PMe 2 Ph, PPh 3 ) serve as models for the assumed intermediate in the formation of metallodithiocarboxylato( S , S ′) metal compounds.

Isonitrilsynthesen am komplex: V. Desulfurierung von isothiocyanaten in carbonylmetallat-additions-verbindungen☆☆☆

Abstract The isocyanide complexes [Fe(η-C 5 H 5 )(CO) 2 CNR][PF 6 ] and Cr(CO) 5 CNR (R = CH 3 , C 6 H 11 , C 6 H 5 ) are conveniently prepared at −50°C from carbonyl metallates, isothiocyanates, and phosgene. At room temperature Na[Fe(η-C 5 H 5 )(CO) 2 ] reacts with isothiocyanates ( 1 1 ) to give the isocyanide bridged complexes [Fe 2 (η-C 5 H 5 ) 2 (μ-CO)(μ-CNR)(CO) 2 ].

Synthesen im system {carbonylmetallat/ketenimin/säure} : I. Iminoacyl- und aminocarbenkomplexe

Abstract [Cr(CO) 5 ] 2 - and [Fe(η-C 5 H 5 )(CO) 2 ] react with R 2 CCNR′ (R  CO 2 Et, R′  Ph; R  Ph, R′ CH 3 , Ph, p -Tol; R  CH 3 , R′ Ph) to give primary adducts containing η 1 -C coordinated ketenimine and secondary products of ferraazetidine-type structure which have been isolated using bulky cations like [ ] + On mono-protonation these species yield iminoacyl, on di-protonation aminocarbene complexes.

Isocyanid- und heteroallen-verbrückte metallkomplexe: IV. Die kristall- und molekülstruktur von trans-anti-bis[η-cyclopentadienyl(μ-phenylisocyanid)(phenylisocyanid)eisen] (FeFe), [Fe(η-C5H5)(μ-CNC6H5)CNC6H5]2− direkter stereochemischer vergleich zwischen brücken- und terminalen isocyanidliganden

Abstract trans-anti-[Fe(η-C5H5)(μ-CNC6H5)CNC6H5]2 crystallizes in the monoclinic space group P21/c (a 8.095(2), b 17.39(2), c 11.064(2) A, β 100.00(2)°) with 1 2 molecule in the asymmetric unit (Z = 2). The two halves are linked together through a strictly planar Fe2C2 rhombus with the four edges having an average distance of 1.920(6) A. Major structural differences are established between terminal and bridging isocyanide ligands, the most significant occurring in the CNC angles of 171.1(6)° vs. 126.4(5)°, and in the CN multiple bond lengths of 1.161(8) vs. 1.242(8) A.

Synthesen im system {carbonylmetallat/ketenimin/säure}: II. Stabile ferraazetidine; röntgenstrukturanalyse von [Fe{C[C(C6H5)2]N(CH3)C}(OC2H5)(η-C5H5)CO]

Upon benzoylation or ethylation, the 1-ferra-3-azetidine structure of [Fe(η-C5H5)(CO)2]-/ketenimine adducts is maintained and ascertained by X-ray structure analysis of [Fe{C[C(C6H5)2]N(CH3)C}(OC2H5)(η-C5H5)CO]. The stereochemistry of the four-membered metallacycle (Pbca, a 9.704(4), b 16.199(7), c 26.384(8) A) is essentially determined by the bond distances FeC(vinyl) (1.993(5) A), FeC(carbene) (1.877(6) A), CC (1.329(8) A), bond angles C(vinyl)FeC(carbene) (66.0(2)°), FeC(vinyl)N(92.4(3)°), FeC(carbene)N (101.9(4)°). Protonation of [Fe{C(CPh2)NPhC}(OC2H5) (η-C5H5)CO] occurs at the exo-C atom of the vinyl group to give the cationic dicarbene chelate complex.

Perturbation par l'oxygène de l'oxydation anodique de l'anion complexe Cr(CO)5CN−

Resume Paramagnetic Cr(CO) 5 CN produced by oxidation of Cr(CO) 5 CN − in non-aqueous media reacts with molecular oxygen. Formation with evolution of variable amounts of CO 2 of a postulated μ-peroxodichromium species depends on the nature of the solvent; DMF is oxidized but acetonitrile not since in this case the starting complex Cr(CO) 5 CN − is oxidized, probably by decomposition products of the μ-peroxo compound.

Isocyanid- und heteroallen-verbrückte metallkomplexe : V. μ3-CS2-komplexe

Zusammenfassung Stepwise metallation of CS 2 gives trinuclear complexes containing the novel μ 3 -CS 2 bridging mode.