Reinhard Nast

Coordination chemistry of metal alkynyl compounds

A. Introduction 90 B. Ionic complex acetylides 90 (i) Anionic complexes of metals 90 (ii) Cationic alkynyl complexes 94 (iii) Zwitterionic alkynyl complexes 94 C. Uncharged low-molecular weight alkynyl complexes 95 (i) Four-coordinate compounds 95 (ii) Fiveand six-coordinate complexes 102 D. Alkynyl compounds of metal-cyclopentadienyl systems 103 (i) Compounds of group IVA metals 103 (ii) Compounds of group IIIA metals 104 (iii) Monocyclopentadienyl compounds of metallocene-forming metals ....... 104 E. Polynuclear complexes of the types [MER], and [M(mR),], 107 F. Alkynyl complexes of d-metal clusters 109 G. Structure and bonding 113 (i) Alkynyl groups as terminal ligands 114 (ii) Alkynyl groups as bridging ligands 117 Acknowledgement 119 Note added in proof 119 References 120

Arylkomplexe des typs trans-[Ir(Ar)(CO)(PPh3)2]

Abstract The preparation and properties as well as some reactions of a series of arylcarbonylbis(triphenylphosphine)iridium(I) complexes [Ir(Ar)(CO)(PPh 3 ) 2 ] (Ar  C 6 H 5 , C 6 F 5 , 2-C 6 H 4 CH 3 , 3-C 6 H 4 CH 3 , 4-C 6 H 4 CH 3 , 2-C 6 H 4 OCH 3 , 2,6-C 6 H 3 -(OCH 3 ) 2 , 4-C 6 H 4 N(CH 3 ) 2 , 3-C 6 H 4 Cl, 4-C 6 H 4 Cl, 4-C 6 H 4 Cl, 3-C 6 H 4 CF 3 , 4-C 6 H 4 CF 3 ) are described, and the most important IR data as well as the 31 P NMR parameters of these, without exception trans -planar, compounds are given. Some of the complexes react with molecular oxygen to form well defined dioxygen adducts [Ir(Ar)(O 2 )(CO)(PPh 3 ) 2 ] (Ar  C 6 H 5 , 3-C 6 H 4 CH 3 , 4-C 6 H 4 CH 3 ). Complexes with ortho -substituted aryl ligands are not oxygenated. This effect is referred to as a steric shielding of the metal center by the corresponding ortho -substituents. With SO 2 the similar irreversible addition compound [Ir(4-C 6 H 4 CH 3 )-(SO 2 )(CO)(PPh 3 ) 2 ] is obtained. Sulfur dioxide insertion into the IrC bond cannot be observed. The first step of the reaction between [Ir(4-C 6 H 4 CH 3 )(CO)(PPh 3 ) 2 ] and hydrogen chloride involves an oxidative addition of HCl to give [Ir(H)(Cl)(4-C 6 -H 4 CH 3 )(CO)(PPh 3 ) 2 ]. IrC bond cleavage by reductive elimination of toluene from the primary adduct does not occur except at elevated temperature.

Alkinylverbindungen von übergangsmetallen : XXXXIII. Ein- und zweikernige alkinylkomplexe von gold(I)

Abstract Preparation and properties of the diamagnetic gold(I) complexes [(C 6 H 5 ) 4 P][RAuR] (R  CN, C 6 H 5 CC) and [(C 6 H 5 ) 4 P] 2 [RAuCCAuR] (R  CN, C 6 H 5 CC, CH 3 CC, HCC) are described. The vibrational spectra and the 31 P NMR spectra of these compounds confirm the linear structure of the complex anions and the existence of discrete phosphonium cations.

Alkinylverbindungen von übergangsmetallen : XXXI. Planare platin(II)koplexe mit p-phenylendiacetylidionen als brückenliganden☆

Abstract By the reaction of cis-[PtCl2(PEt32] with the disodium salt of p-phenylenediethynyl, 1,4-NaCCC6H4CNa, the binuclear planar complex trans-[(Et3P)2(Cl)PtCCC6H4CCPt(Cl)(PEt3)2] has been obtained. Other neutral comlexes of the type trans-[(Et3P)2(X)PtC2C6H4C2Pt(X)(PEt3)2] (X = Br, I, NCS, H) and cationic complexes of the trype trans-[(Et3P)2(L)PtC2C6H4C2Pt(L) (PEt3)2](ClO4)2 (L = CO, PEt3, pyridin) can be prepared from this compound by substitution reactions. The structures of these compounds have been determined by 31P and 1H NMR spectroscopy and that of th N-thiocyanato complex has been confirmed by X-ray studies. The IR and Raman spectra are discussed.

Alkinylverbindungen von übergangsmetallen

The preparation and the properties of the diamagnetic planar complexes trans-[Ni(CCR′)2(PR3)2] (R′ = o-C6H4CCH, p-C6H4CCH; R = n-C4H9, C6H5) are described. The trans-planar structure of the complex Ia (R′ = o-C6H4CCH, R = n-C4H9) recently demonstrated by X-ray studies, is confirmed also for the other compounds by IR, NMR (1H, 31P, 13C) and dipole measurements. The NiC distances observed in Ia indicate some double bond character of this bond.

Metallorganische verbindungen des 1,4-diethinylbenzols vom typ p-C6Hn4(C=CMR3)2 (M = Si, Ge, Sn, Pb)

Abstract The preparation and properties of the compounds 1, 4-C6H4(CCMR3)2 (M  Si, Ge, Sn, Pb, R  CH3; M  Sn, Pb, R  C6H5) are described. The structures and bondings proposed for these molecules are supported by mass spectroscopy, IR, Raman, 1H NMR and 13C NMR data.

Alkinylverbindungen von übergangsmetallen : XXXIII. Planare palladium(II)-komplexe mit o-ethinylphenylacetylid-ionen als liganden

Abstract By the reaction of trans-[Pd(PEt 3 ) 2 X 2 ] with solutions of o -diethynylbenzene 1,2-HCCC 6 H 4 CCH in liquid ammonia the complexes trans -[Pd(PEt 3 ) 2 (X)-( o -C 2 C 6 H 4 C 2 H)] (X  Cl, Br, I) have been prepared. The corresponding pseudo-halide complexes trans -[Pd(PEt 3 ) 2 (X′)( o -C 2 C 6 H 4 C 2 H)] X′  NCS, CN) could be formed from these complexes by substitution reactions. The molecular structures of all these complexes have been determined by 31 P and 1 H NMR data, that of the N -thiocyanato complex has been confirmed by X-ray studies. The IR and Raman spectra as well as the dipole moments of the complexes are discussed.

Alkinylverbindungen des thalliums

Zusammenfassung Durch Umsetzung von (CH 3 ) 2 TlNH 2 mit Alkinen in fl. NH 3 konnten die Dimethylthalliumacetylide (CH 3 ) 2 TlC (R = C 6 H 5 , CH 3 ) sowie das (CH 3 ) 2 TlCCTl(CH 3 ) 2 dargestellt werden. Ausgehend von TlCl 3 ·4NH 3 wurden ferner durch Umsetzung mit MCCR komplexe Acetylide des Typs M[Tl(CCR) 4 ] [R = C 6 H 5 , CH 3 ; M = Na, K, (C 6 H 5 ) 4 P] erhalten. Auf Grund kryoskopischer Untersuchungen und Leitfahigkeitsmessungen erweisen sich die Verbindungen als einkernige schwache Elektrolyte. Ihre IR-Spektren werden diskutiert.

Alkinylverbindungen von übergangsmetallen : XXXIX. Planare palladium(II) komplexe des typs trans-[p-C6H4(CCPd(X)(PEt3)2)2](n+2)+ (n = summe der ionenladungen von X)

Abstract Preparation and properties of the diamagnetic planar complexes trans-[p-C6H4(CCPd(X)(PEt3)2)2] (X = Cl, Br, I, NCS) and trans-[p-C6H4(CCPd(X)(PEt3)2)2](ClO4)2 (X = PEt3, pyridine) are described. The structures of the compounds have been determined by 31P and 1H NMR spectroscopy. The IR spectra are discussed.

Metallorganische verbindungen des 1,2-diethinylbenzols vom typ o-C6H4(CCMR3)2 (M = Si, Ge, Pb)

Abstract The preparation of the compounds o -C 6 H 4 (CCMR 3 ) 2 (M = Si, Ge, Pb; R = CH 3 ; M = Pb; R = C 6 H 5 ) is described. Their properties are compared with those of o -C 6 H 4 (CCSnR 3 ) 2 (R = CH 3 , C 6 H 5 ) and those of their p -isomers. The structures and bonding conditions proposed for these molecules are supported by dipole measurements, mass spectroscopy, IR, Raman, 1 H NMR and 13 C NMR data.