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2,6-Di-tert-butyl-4-iodophenol (1) does not react to the keto carbene 4 under strongly basic conditions and exclusion of oxygen, in contrast to a report in the literature. In the presence of oxygen, however, oxidation takes place. Reaction times and product pattern strongly depend on the concentration of O2. Besides biphenyl 2, diphenoquinone 3, and quinone 5, a new (oxocyclohexadienylidene)bisphenol 6 was isolated, and its molecular structure was determined by X-ray crystallography. A radical mechanism is suggested for the formation of the above products from 1. The bisphenol 6 was also synthesized by thermolysis of the quinone diazide 11 in the presence of 3.

By the reaction of transition metal ions (Cu2.Ni2′) with 1,2-diselenooxalate the first selenooxalato complexes have been synthesized. The structure of the nickel complex, bis(1,2-diselenooxalato)nickelate(II).(BzlPh8P)2[Ni(dso)2], has been determined by X-ray diffraction. The analogous Cu(II) complex. [Cu(dso)2]2, was identified by its ESR spectrum characterized by the following parameter set: go = 2.042 and the 64Cu and 77Se hypertine coupling constants a o co = 79.1 × 10 4 cm 1 and a a Se = 48.6 × 10 4 cm 1 . respectively.

[NEt4]2[Tc(Cl)3(CO)3] was prepared directly from [NBu4][TcO4]. Dissolution of [NEt4]2[Tc(Cl)3(CO)3] in water yielded the aqua ion [Tc(OH2)3(CO)3]+ which, upon titration with 1 eq. of OH−, gave the tetranuclear complex [{Tc(μ3-OH)(CO)3}4] in quantitative yield and of which the structure could be elucidated. Reaction of [{Tc(μ3−OH)(CO)3}4] with HC5Me5 gave the important starting material [(C5Me5)M(CO)3] (M = Tc, Re). To achieve complexes in higher oxidation states with the C5Me5− ligand, oxidation was performed with [Br2] for the rhenium and the corresponding technetium complex. Oxidation in trifluoroacetic acid yielded cis/trans-[(C5Me5)M(Br)2(CO)2] (M = Tc, Re). Oxidation in dichloromethane gave in both cases the seven co-ordinate, 18e− M(III) complex [(C5Me5)MBr(CO)3]+. The structure of the rhenium complex was elucidated. It was found that oxidation took place at the metal centre and the C5Me5− ring to yield [(CO)3M(μ−Br)3M(CO)3] as the counterion.

Complexes of the general formula |M(CO)3[(Ph2PS)2N](CH3CN)| (M = Tc, Re) have been prepared by the reaction of (Et4N)2[M(CO)3X3] (M = Tc, Re; X = Cl, Br) with sodium bis(diphenylthiophosphoryl)amide, Na[(Ph2PS)2N], in acetonitrile. The metal is six-coordinate with facially arranged carbonyl ligands. Bis(diphenylthiophosphoryl)amide is deprotonated and bonded as S,S′-chelate with TcS distances of 2.526(3) and 2.546(3) A. Acetonitrile occupies the sixth coordination position. The rhenium compound is isomorphous and the bonding situation in |Re(CO)3[Ph2PS)2N](CH3CN)| is similar to that in its technetium analogue. (Et4N)[Re(CO)3Br2(CH3CN)] crystallizes from a hot acetonitrile solution of (Et4N)2[Re(CO)3Br3] despite the fact that in solution only [Re(CO)3(CH3CN)3]+ can be detected spectroscopically. It has a facial arrangement of CO groups in an octahedral co-ordination geometry.

The compound [NBu4][ReNCl4] has been found to be easily accessible by the reaction of [NBu4][ReO4] with sodium azide and HCl gas in ethanol and represents an excellent precursor for the synthesis of further rhenium nitrido complexes. It has been studied by X-ray crystallography. Rhenium(VI) compounds of the general formula [ReNX4(5)]–,2– (X = Br or NCS) were obtained when [NBu4][ReNCl4] reacts with HBr or KSCN. The products as well as mixed-ligand intermediates which are formed during the ligand exchange have been studied by EPR spectroscopy. The EPR parameters of the individual mixed-ligand compounds are clearly correlated to the composition of the co-ordination sphere and can be used to characterize the mixed-ligand species unambiguously. This is shown by a nearly linear dependence of g0, g||, a0Re and A||Re on the spin–orbit coupling constants of the equatorial donors. Reactions of [NBu4][ReNCl4] with most organic ligands yielded rhenium(V) compounds. A number of phosphine complexes and chelates with sulfur-containing ligands have been prepared and spectroscopically characterized. A crystallographic study on [ReN(Hdetcb)2] (Hdetcb– = N 2-diethylthiocarbamoylbenzamidinate) shows cis co-ordination for the chelating S,N-donor ligands. Weak intermolecular hydrogen bridges have been found between the co-ordinated nitrogen atoms and the lone pair of the nitrido nitrogen. A comparison between the crystal structural data of [NBu4]2[ReN(mnt)2] (mnt2– = 1,2-dicyanoethene-1,2-dithiolate), prepared from [NBu4][ReNCl4] and Na2mnt, and [NBu4][ReO(mnt)2] shows longer Re–S bonds in the nitrido anion but markedly higher O–Re–S bond angles indicating higher steric requirements of the oxo ligand compared with ‘N3–’.

The synthesis and characterization of novel indium(III) complexes with pyridine-thiosemicarbazone ligands are reported as well as ligand exchange reactions on the products. 2,6-Diacetylpyridine-bis(thiosemicarbazone), C5H3N(C3N3SH6)2 (H2DAPTSC), and 2-acetylpyridine-thiosemicarbazone, C5H4N(C3N3SH6) (HAPTSC), were reacted with indium(III) halides and indium(III) nitrate, respectively, to give [InX2(HDAPTSC)], {O[In(HDAPTSC)(OH)]2}, [InX2(APTSC)(MeOH)] and [In(APTSC)2]PF6.

[InCl3(L1)(MeOH)] [L1 = pyridine-2,6-bis(acetyloxine), 2,6-C5H3N(C2H3NOH)2] reacts with bidentate ligands by ligand exchange. A seven-coordinate complex of the composition [In(L1)Cl(ox)(OH2)] is formed with potassium oxalate (K2ox). The oxalato ligand occupies the equatorial plane of a pentagonal bipyramid together with the tridentate amine oxime. With sodium 1,2-dicyanoethene-1,2-dithiolate (Na2mnt) the analogous reaction produces a six-coordinate mixed ligand complex, [In(L1)Cl(mnt)], which has a distorted octahedral coordination sphere. Ligands which form four-membered chelate rings like dialkyldithiocarbamates, R2dtc−, or pyridine-2-thiolate, pythio−, are able to replace all ligands of [InCl3(L1)(MeOH)] to form neutral tris chelates. The structure of [In(pythio)3] has been elucidated showing a strong distortion of the coordination polyhedron from the idealized octahedral geometry.

A detailed investigation of the one-pot synthesis of [NEt4]2[MX3(CO)3] [M=Tc (1a) or Re (1b); X= Cl−, Br−] is presented. The intermediates [NEt4][Tc2-(μ-Cl)3(CO)6] (2a), [NBu4][Tc3(μ3-H)(μ-H)3(CO)9] (3) and [Tc3(μ-H)3(CO)12] (4) have been isolated and characterized. The X-ray structure of (2a) is described. Complex (2a) crystallizes in the monoclinic space group P21/c with a=19.491(6), b=18.323(2) and c=17.497(9)AA, and β=97.59(2)°. Quantitative conversion of (2a), (3) and (4) into the aqua-ion [M(OH2)3(CO)3]+ [M=Tc (5a) or Re (5b)] is described. To evaluate an optimal and simple chelating group for the “fac-M(CO)3” moiety, the reaction with the bidentate thioether ligand Cl(CH2)2S(CH2)2S(CH2)2Cl (qyp) has been investigated and the structure of the neutral complex [ReBr(qyp)(CO)3] (6) is described. Complex (6) crystallizes in the monoclinic space group P21/c with a=15.935(6), b=2.788(4) and c= 7.955(10)AA, and β=98.57(1)°. To extend the knowledge about substitution chemistry of organometallic complexes in aqueous solution, the acetato ligand [OOCCH3]− has been reacted with (1b), resulting in the formation of the dinuclear, acetato-bridged complex [NEt4][Re2(μ-OH)2(μ-OAc)(CO)6], which converted into [Re2(μ-OEt)2(μ-OAc)(CO)6]− (7) after recrystallization from EtOH. The X-ray structure of (7) has been determined. Complex (7) crystallizes in the monoclinic space group P21/c with a=16.288(3), b=12.4272(10) and c=13.620(3)AA, and β=76.63(1)°. For a future application of the small “fac-M(CO)3” moiety, it seems thus advantageous to combine these two ligand groups in one simple chelating function.

2,6-Bis(acetyloxime)pyridine, 2,6-C5H3N(C2H3NOH)2 (L1), reacts with indium(III) chloride in methanol to give the seven-coordinate complex [InCl3(L1)(MeOH)]. The structurally similar Schiff base ligand 2,6-bis(1-phenyliminoethyl)pyridine (L2), 2,6-C5H3N(C2H3NC6H5)2, however, forms a six-coordinate indium(III) complex of the composition [InCl3(L2)]. The InN bond distances are longer by 0.03–0.12 A in the seven-coordinate compound compared with those in the Schiff base complex. The MeOH ligand in [InCl3(L1)(MeOH)] can be replaced by Cl− or H2O to give the complex anion [InCl4(L1)]− and [InCl3(L1)(OH2)], respectively. The pentagonal-bipyramidal coordination environment of the metal is preserved during these reactions.

Technetium(V) and rhenium(V) nitrido complexes of the compositions [MNL 2 ] and [MN(Cl)(PPhMe 2 )L] have been synthesized by reaction of Na[N(SPPh 2 ) 2 ] and [MNCl 2 (PPh 3 ) 2 ] or [MNCl 2 (PPhMe 2 ) 3 ] complexes, respectively [M = Re or Tc; L = N(SPPh 2 ) 2 - ]. The amide anion acts in all isolated complexes as a chelating ligand co-ordinated via the sulfur atoms. The complexes [TcN{N(SPPh 2 ) 2 } 2 ], [ReN{N(SPPh 2 ) 2 } 2 ] and [TcN(Cl)(PPhMe 2 ) 2 {N(SPPh 2 ) 2 }] have been studied by X-ray crystallography. The bis-chelates are five-co-ordinate with the nitrogen atoms at the apexes of square pyramids. The Tc atom in [TcN(Cl)(PPhMe 2 ) 2 {N(SPPh 2 ) 2 }] has a distorted-octahedral co-ordination sphere with Cl bonded trans to the nitrido function. The complex [ReN{N(SPPh 2 ) 2 } 2 ] is the first five-co-cordinate nitride which reacts with BCl 3 to form a nitrido bridge between rhenium and boron; [Re(NBCl 3 ){N(SPPh 2 ) 2 } 2 ] is characterized by a covalent N–B bond of 1.539(5) A. The Re–N multiple bond distance is only slightly influenced by addition of the Lewis acid. The complex [ReN(Cl)(PPhMe 2 ) 2 {N(SPPh 2 ) 2 }] reacts with BCl 3 with substitution of N(SPPh 2 ) 2 - and formation of the well known [Re(NBCl 3 )Cl 2 (PPhMe 2 ) 3 ]. The corresponding technetium complexes do not form Tc–N–B bridges upon reactions with BCl 3 . The [MN(Cl)(PPhMe 2 ) 2 {N(SPPh 2 ) 2 }] (M = Tc or Re) complexes reacted with S 2 Cl 2 to give thionitrosyl compounds with the metals in lower oxidation states; [Re(NS)Cl 2 (PPhMe 2 ) 3 ] and [Re(NS)Cl 3 (PPhMe 2 ) 2 ] have been characterized spectroscopically, [Tc(NS)Cl 3 (PPhMe 2 ) 2 ] was studied by X-ray diffraction and EPR spectroscopy. The phosphine ligands are trans to each other.

The anionic rhenium(I) complex fac-[Re(CO)3Br3]2− has been reacted with thiourea (tu), N,N-dialkylbenzoylthioureas (HR2btu) and N,N-dialkylthiocarbamoylbenzamidines (HR12tcbR2) to give novel mono- and binuclear rhenium(I) complexes. All new compounds are air-stable and non-sensitive against aqueous media. Fac-[Re(CO)3(tu)3] (NO3) is formed from the bromo complex by precipitation of AgBr after addition of AgNO3 and subsequent reaction with thiourea. The compound co-crystallizes with one molecule of (Et4N) NO3 in the monoclinic space group P2 1 /n,a = 143675(3), b = 13.372(1), c = 28.841 (7) A , s = 102.53(1)°, Z = 8 . The mean ReS bond length is 2.529 A. N,N-Dialkylbenzoylthioureas react with (Et4N)2[Re(CO)3)Br3] to form neutral [Re(CO)3Br(HR2btu)] complexes. With the rhenium(I) centers under study they coordinate bidentately, but without deprotonation, which is unusual for this class of chelate ligands. [Re(CO)3Br(HEt2btu)] crystallizes in the triclinic space group P 1 , a = 8.080(2), b = 9.254(3), c = 13.761(5) A α = 76.60(2), s = 88.66(2), γ = 70.92(3)°, Z = 2. The chelate ring shows significant deviations from planarity which underline the absence of an extended π-system. Complexes of different composition are formed with thiocarbamoylbenzamidines depending on the sterical requirements of the individual ligands. A binuclear compound could be isolated with N,N-diethylthiocarbamoylbenzamidinate (Et2tcbH−). [Re2(CO)6−(Et2tcbH)2] crystallizes in the monoclinic space group P2 1 /c, a = 10.859(4), b = 17.409(2), c = 9.159(5) A , s = 79.15(2)°, Z = 2 . Both rhenium atoms are coordinated by three facially arranged carbonyls and a singly deprotonated Et2tcbH− ligand. The sulfur atoms of these ligands act as bridges between the metal centers forming a four-membered Re2S2 ring. Two slightly different ReS bond lengths are observed in this ring system (2.507(2) and 2.545(2) A). Only a mononuclear, anionic complex is formed with the more bulky benzamidine ligand N(N-morpholinylthiocarbonyl)-N′-phenylbenzamidine (Hmorphtcbph). (Et4N) [Re(CO)3Br(morphtcbph)] crystallizes in the triclinic space group P 1 , a = 10.018(4), b = 10.065(4), c = 16.720(7) A , α = 80.90(3), s = 79.82(3), γ = 70.81(4)°, Z = 2 . The rheniumsulfur distance is 2.476(2) A.

[MoCl4(Ph-C≡C-Se-C4H9)(SEt2)] has been prepared by the reaction of trans-[MoCl4(SEt2)2] with Ph-C≡C-Se-C4H9 in dichloromethane solution. The complex was characterized by IR spectroscopy and by a crystal structure determination. Space group P21/c. Z = 4. structure solution with 4595 independent reflections. R = 0.057 for reflections with I > 2σ(I). Lattice dimensions at -65°C: a = 1002.8(2). b = 730.74(5), c = 2703.1(7) pm. β = 95.78(1)°. The complex has a molecular structure in which the molybdenum atom is seven-coordinate by four chlorine ligands, by the two alkyne carbon atoms, and in irons position to the latter by the sulfur atom of the thioether molecule. The MoC bond lengths of 190.2 and 200.9 pm are surprisingly different.

Von Dichlorotris(dimethylphenylphosphan)-nitridotechnetium(V), [TcNCl2(MePhP)3] werden durch schrittweisen Ligandenaustausch mit Diethyldithiocarbamat Komplexe der Zusammensetzung [TcN(Cl)(Me2PhP)2(Et2dtc)], [TcN(Me2PhP)(Et2dtc)2] und [TcN(Et2dtc)2] dargestellt. Die Reaktion mit N,N-Diethylthiocarbamoylbenzamidin, H2Et2tcb, liefert dagegen in guten Ausbeuten das Bis-Chelat. Als einziges Intermediat der Reaktion last sich [TcN(Cl)(Me2PhP)2-(HEt2tcb)] isolieren. [TcN(Me2PhP)(Et2dtc)2] kristallisiert in der monoklinen Raumgruppe P21/c mit a = 17,369(5) A, b = 15,024(1) A, c = 9,906(3) A, β = 76,47(1)o, Z = 4. Der Me2PhP-Ligand ist aquatorial koordiniert. Die auffallig kurze Mehrfachbindung zwischen Technetium und Stickstoff (Bindungslange TcN(1) 1,624(3) A) wirkt sich stark labilisierend auf das trans-standige Donoratom aus (Abstand TcS(4) 2,826(1) A). [TcN(HEt2tcb)2] kristallisiert in der triklinen Raumgruppe P1, mit a = 9,749(4) A, b = 11,264(4) A, c = 12,359(4) A, α = 75,34(2)o, β = 79,69(2)o, γ = 87,55(2)o, Z = 2. Das Koordinationspolyeder ist eine quadratische Pyramide, deren Spitze vom Nitridoliganden besetzt ist. Ihre Grundflache wird von den Donoratomen der cis-koordinierten Chelatliganden gebildet. Das Metall befindet sich um etwa 0,6 A uber der Grundflache. Der TcN-Abstand betragt 1,610(5) A. Mixed-ligand Complexes of Technetium. XV. The Reaction of [TcNCl2(Me2PhP)3] with Dialkyldithiocarbamates and N,N-Dialkylthio-carbamoylbenzamidines [TcN(Cl)(Me2PhP)2(Et2dtc)], [TcN(Me2PhP)(Et2dtc)2], and [TcN(Et2dtc)2] can be prepared by stepwise ligand exchange reactions starting from dichlorotris(dimethylphenylphosphine)nitridotechnetium(V), [TcNCl2(Me2PhP)3], and diethyldithiocarbamate. In contrast to this, only one intermediate, [TcN(Cl)(Me2PhP)2(HEt2tcb)], could be isolated during the reaction with N,N-Diethlthiocarbamoylbenzamidine, which yields the bis chelate [TcN(HEt2tcb)2]. [TcN(Me2PhP)(Et2dtc)2] crystallizes in the monoclinic space group P21/c; a = 17.369(5) A, b = 15.024(1) A, c = 9.906(3) A, β = 76.47(1)o, Z = 4. The phosphine is coordinated equatorially. The multiply bonded nitrogen ligand (TcN(1) 1.624(3) A) strongly labilizes the trans positioned donor atom (distance TcS(4) 2.826(1) A). [TcN(HEt2tcb)2] crystallizes in the triclinic space group P1 with a = 9.749(4) A, b = 11.264(4) A, c = 12.359(4) A, α = 75.34(2)o, β = 79.69(2)o, γ = 87.55(2)o, Z = 2. The metal is five-coordinate with the nitrido donor atom occupying the apex of a square pyramid. It's basal plane is formed by the cis-coordinated chelate ligands. The technetium is situated over the basal plane by about 0.6 A. The TcN distane was found to be 1.610(5) A.

Die Titelverbindungen werden durch Reaktionen von CoI2 bzw. ZnI2 mit dem silylierten Phosphanimin Me3SiNPMe3 durch Schmelzreaktion bei 180°C in Gegenwart von Natriumfluorid synthetisiert. Sie kristallisieren aus Dichlormethan als dunkelgrune (Co) bzw. farblose (Zn) Einkristalle mit drei Molekulen Dichlormethan pro Formeleinheit, die wir durch Kristallstrukturanalysen charakterisiert haben. [CoI(NPMe3)]4 · 3 CH2Cl2: Raumgruppe P3m1, Z = 2, Strukturlosung mit 2376 unabhangigen Reflexen, R = 0,033. Gitterkonstanten bei −50°C: a = b = 1455,8; c = 1270,5 pm. [ZnI(NPMe3)]4 · 3 CH2Cl2: Raumgruppe P3m1, Z = 2, Strukturlosung mit 2197 unabhangigen Reflexen, R = 0,043. Gitterkonstanten bei −60°C: a = b = 1454,9; c = 1270,5 pm. Die beiden miteinander isotypen Verbindungen bilden Heterocuban-Strukturen, in denen die Metallatome uber μ3-N-Brucken der Phosphaniminato-Gruppen verknupft sind mit M4N4-Bruckenbindungswinkeln nahe bei 90°. Phosphoraneiminato Complexes of Cobalt and Zinc with Heterocubane Structure. Crystal Structures of [CoI(NPMe3)]4 and [ZnI(NPMe3)]4 The title compounds have been prepared from CoI2 and ZnI2, respectively, and Me3SiNPMe3 by fusion reactions at 180°C in the presence of sodium fluoride. They crystallize from dichloromethane as dark green (Co) or colourless (Zn) single crystals including three molecules CH2Cl2 per formula unit, which were characterized by crystal structure determinations. [CoI(NPMe3)]4 · 3 CH2Cl2: Space group P3m1, Z = 2, structure solution with 2376 independent reflections, R = 0.033. Lattice dimensions at −50°C: a = b = 1455.8, c = 1270.5 pm. [ZnI(NPMe3)]4 · 3 CH2Cl2: Space group P3m1, Z = 2, structure solution with 2197 independent reflections, R = 0.043. Lattice dimensions at −60°C: a = b = 1454.9, c = 1270.5 pm. Both complexes are isostructural with one another. They form heterocubane structures in which the metal atoms are linked via μ3-N-bridges of the phosphoraneiminato groups with M4N4 bridge-type bond angles close to 90°.

Ausgehend von [MOCl4]−-Komplexen werden mit dem vierzahnigen Amin-Phenolato-Liganden N,N-Bis(2-hydroxybenzyl)-1,3-diamino-2-4-nitrobenzyl)propan (H2L1) Rhenium(V)- und Technetium(V)-Chelate hergestellt und strukturell charakterisiert. Es entstehen sauerstoffverbruckte, neutrale Zweikernkomplexe mit einer zentralen [OMOMO]4+-Einheit. Der Ligand koordiniert jeweils vierzahnig unter Deprotonierung der Phenolfunktionen. [OTcL1OL1TcO] · H2O kristallisiert monoklin in der Raumgruppe P21/c mit a = 10,633(2); b = 13,705(1); c = 16,364(3) A; β = 94,65(1)°; Z = 2. Zwei TcOL1-Einheiten mit je einem terminalen Oxo-Liganden sind uber eine Sauerstoff-Brucke miteinander verknupft. Das Metall befindet sich in einer verzerrt oktaedrischen Umgebung. Fur die TcO-Bindung der nahezu linearen OTcOTcO-Einheit wurden zwei unterschiedliche Bindungsabstande bestimmt (TcO(terminal): 1,655(7) A und TcO(Brucke): 1,903(1) A. Die analoge Rheniumverbindung kristallisiert in der gleichen Raumgruppe mit a = 13,302(7); b = 9,956(1); c = 17,535(9) A; β = 106,72(2)°; Z = 2. Fur das ebenfalls dimere Komplexmolekul [OReL1OL1ReO] konnten ahnliche Bindungsverhaltnisse wie fur sein Technetium-Analogon bestimmt werden. Synthesis and Characterization of μ-oxo Dimeric Technetium and Rhenium Complexes with Functionalized Amine Phenolate Ligands. X-Ray Crystal Structures of [OTcL1OL1TcO] · H2O and [OReL1OL1ReO] Complexes (H2L1 = N,N′-bis(2-hydroxybenzyl)-1,3-diamino-2-(4-nitrobenzyl)propane) Neutral rhenium(V) and technetium(V) chelates with the tetradentate amine phenolate ligand N,N′-bis(2-hydroxybenzyl)-1,3-diamino-2(-4-nitrobenzyl)propane (H2L1) have been prepared from [MOCl4]− complexes and structurally characterized. The ligand coordinates tetradentately with deprotonation of the phenolic oxygen atoms. [OTcL1OL1TcO] · H2O crystallizes monoclinic in the space group P21/c with a = 10.633(2), b = 13.705(1), c = 16.364(3) A; β = 94.65(1)°, Z = 2. Two TcOL1 units with each one terminal oxo core are connected by a μ-oxo ligand. The technetium atoms are situated in distorted octahedral coordination spheres. Two distinct TcO bond lengths have been found for the almost linear OTcOTcO unit (TcO(terminal): 1.655(7) A and TcO(μ-oxo): 1.903(1)) A. The analogous rhenium compound crystallizes in the same space group with a = 13.302(7), b = 9.956(1), c = 17.535(9) A; β = 106.72(2)°, Z = 2. The dimeric [OReL1OL1ReO] complex has a structure which is very similar to that of the corresponding technetium compound.

Losungen von O-Methyl-1,1-dithiooxalat (i-dtoMe) und Metall(II)-chloriden (NiII, PdII) im molaren Verhaltnis 2:1 reagieren mit equimolaren Mengen gleichkerniger Bischelate anderer 1,1- und 1,2-Dithioverbindungen L (L = i-mnt, Etxan, dto)1 unter Ligandenaustausch zu Gemischtligandenkomplexen M(ptoMe)L bei spontaner Umwandlung des 1,1-Dithiooxalates zum entsprechenden Perthioliganden (ptoMe) durch Schwefelinsertion. Tetraphenylphosphonium (1,1-dicyanoethen-2,2-dithiolato)(O-methyl-1,1-perthiooxalato)niccolat(II), Ph4P[Ni(i-mnt)(ptoMe)], kristallisiert in der monoklinen Raumgruppe P21/n mit a = 11,019(2) A, b = 13,648(3) A, c = 20,882(3) A, β = 92,565(7)°. Die Bildung des Perthioliganden konnte mittels 13C-NMR bestatigt werden. New Mixed Ligand Complexes with Perthio Carboxylates Solutions of O-methyl-1,1-dithiooxalate (i-dtoMe) and metal(II)-chlorides (NiII, PdII) in the molar ratio 2:1 react with equimolar amounts of homonuclear bischelates of other 1,1- and 1,2-dithio-compounds L (L = i-mnt, Etxan, dto) to mixed ligand complexes M(ptoMe)L with spontaneous convertion of the 1,1-dithiooxalate into the corresponding perthio ligand (ptoMe) by sulfur insertion. Tetraphenylphosphonium-(1,1-dicyanoethene-2,2-dithiolato)(O-methyl-1,1 -perthio-oxalato)niccolat(II), Ph4P[Ni(i-mnt)(ptoMe)], crystallizes in the monoclinic space group P21/n with a = 11.019(2) A, b = 13.648(3) A, c = 20.882(3) A, β = 92.565(7)°. The formation of the perthio ligand is confirmed by 13C-NMR.

Synthesis of N-[2(1H-pyrolylmethyl)]-N′-(4-pentene-3-one-2)ethane-1, 2-diamine has been effected and the compound characterised by X-ray diffraction. Crystal data for C12H19N3O: space group P21/c: a=10.358(3), b=7.953(1), c=15.640(4) A, β=101.63(1)°, V=1261(2) A3 to give Z=4 for D=1.165 g cm−3. Structure solution and refinement based on 2114 reflections converged at R=0.064, Rw=0.079. Reaction of this molecule with Bu4N[TcO(ethylene glycolate)2] results in the formation of a neutral technetium(V) complex [TcOL]. The X-ray structure of this complex confirms a five-coordinate, square based pyramidal geometry with no crystallographic axes of symmetry. Crystal data: orthorhombic space group P212121; a=11.701(1), b=14.949(2), c=7.516(1) A, V=1314.6 A3 to give Z=4 for D=1.68 g cm−3. Structure resolution and refinement based on 2115 reflections converged at R=0.037, Rw=0.033. Reaction of N-[2(1H-pyrolylmethyl)]-N′-(4-pentene-3-one-2)ethane-1,2-diamine with rhenium(V) oxotrichlorobistriphenylphosphine [ReOCl3(PPh3)2] or a rhenium(V) glycolato precursor yields the [ReOL] complex. The compounds have been studied by NMR, UVVis, IR spectroscopy as well as by mass spectrometry. The obtained results have been discussed in terms of the complex formation and the different transition metals.

Bis(tetrabutylammonium)bis( 1,1 -dicyanoethene-2,2-diselenolato)nitridotechnetate( V), (Bu4N)2[TcN(i-mns)2] has been prepared by the reaction of (Bu4N)TcNCl4 with the potassium salt of the ligand and Bu4NBr. The compound forms yellow crystals which were characterized by elemental analysis, IR and UV/VIS spectrometry, mass spectroscopy as well as X-ray structure determination. The compound crystallizes triclinic in the space group P 1̄ with Z = 2. The final R value is 0.045. In the complex anion the five-coordinate technetium atom exhibits a square pyramidal environment with the selenium donors in the basal plane and the nitrido ligand in the apical position. The bond length Tc≡=N = 161(1) pm is within the normal range of TcN triple bonds.

Der Titelkomplex entsteht in guten Ausbeuten bei der Umsetzung von (Bu4N)ReOBr4 oder ReOCl3(Ph3P)2 mit der triphenylmethyl-geschutzten Form des vierzahnigen Liganden. Die Struktur des Chelats als neutrale Oxoverbindung des Rheniums (V) wird durch analytische sowie 1H-, 13C-NMR, IR-, UV/Vis- und massenspektrometrische Untersuchungen gestutzt. Synthesis and Characterization of [N-(2-Mercaptoacetyl)-N′ -4-(penten-3on-2)ethylen-1,2-diaminato]oxorhenium(V), ReO(MRP 40) The title complex is obtained in good yields from the reaction of the triphenylmethyl-protected ligand with (Bu4N)ReOBr4 or ReOCl3(Ph3P)2. The structure of the compound as neutral oxorhenium(V) complex is confirmed by analytical, 1H-, 13C-NMR, IR, UV/Vis as well as mass spectrometric studies.

Diamagnetic nitridotechnetium(V) complexes with tri- and tetradentate azomethine ligands which possess electron withdrawing groups in their periphery can be prepared starting from TcNCl 2 (Ph 3 P) 2 or (in the case of the tetradentate ligands) TcNX 4 − (X = Cl, Br). The products are air stable compounds which have been characterized by elemental analysis, infrared and UV-Vis spectroscopy, NMR and mass spectrometry. The mixed-ligand complex [ N -(2-Ethoxycarbonyl-3-oxo-but-l-en(1)yl)-2-aminophen- olato](triphenylphosphine)nitridotechnetium(V) (C 31 H 28 N 2 O 4 PTc, M r = 622.5) crystallizes monoclinic in the space group C 2/ c . The coordination geometry is a distorted square pyramid with the nitrido ligand at the apex.

{ N-(2-Mercaptoacetyl)-N′-[4-(pentene-3-one-2)]ethane-1,2-diaminato} oxotechnetium(V) has been prepared by the reaction of (Bu4N)TcOX4 complexes (X = Cl, Br) with N-(mercaptoacetyl)-N′-[4-(pentene-3-one-2)]ethane-1,2-diamine in methanolic solution. The compound forms dark red crystals which were characterized by elemental analysis, IR and 1H NMR spectroscopy, mass spectrometry, as well as an X-ray structure determination. The compound crystallizes triclinic in the centrosymmetric space group PĪ with a = 776.50(3), b = 819.69(6), c = 1040.43(7) pm, α = 92.944(6)°, β = 110.805(5)° and γ = 109.957(5)°. The final R value is 0.023. In the monomeric complex the five coordinate technetium atom exhibits a square pyramidal environment with the donors of the tetradentate ligand in the basal plane and the oxo ligand in the apical position. The bond length Tc–O = 165.7(2) is within the normal range of Tc=O double bonds.

Dimeric units of the almost planar title compound, C 8 H 11 N 4 S + .Cl - , are formed by N-H. . -Cl hydrogen c- bonds between the Cl- anion and the H atom of the to protonated pyridinium N atom, one H atom of the terminal NH2 group of one thiosemicarbazone molecule and the second NH2 H atom of a second molecule. The dimeric units are stacked in layers. The C-S bond length is 1.681 (3) A and considerable double-bond character can be detected for the C-N bonds.

mer-[TcCl3(Me2PhP)3] reacts with potassium thiocyanate with the replacement of only one Cl− ligand by NCS− and forms selectively (OC-6–12)dichlorotris(dimethylphenylphosphine)(thiocyanato-κN)technetium(III) {mer,trans-[TcCl2(NCS)(Me2PhP)3]}. No evidence could be found for the formation of the cis analogue. The title compound crystallizes in monomeric units. The Tc atom is coordinated in a distorted octahedral manner with the two chloride ligands in trans positions to each other. The NCS− ligand is N-bonded with a Tc—N bond length of 2.104 (3) A.

The title compound, [TcCl 2 (C 4 H 10 O 2 PS 2 )(C 8 H 11 P) 2 ], is formed during the reaction of [TcNCl 2 (Me 2 PhP) 3 ] with excess sodium diethyldithiophosphate involving cleavage of the technetium-nitrido bond. The Cl ligands are trans with respect to each other, with a mean Tc-Cl distance of 2.3545 (6) A. The diethyldithiophosphate is bonded as a chelate ligand with Tc-S bond lengths of 2.4639 (7) and 2.4787 (6) A.

Starting originally from the organometallic precursor [NEt(4)](2)[TcBr(3)(CO)(3)] (1b), substitution reactions were performed with the macrocyclic thioethers 1,4,7-trithiacyclononane (9-ane-S(3)), 1,4,7,10,13,16-hexathiacyclooctadecane (18-ane-S(6)), and 3,6,9,13,16,19-hexathiacycloicosanol (20-ane-S(6)-OH). The corresponding complexes fac-[Tc(9-ane-S(3))(CO)(3)]Br (2), fac-[Tc(2)(tosylate)(2)(18-ane-S(6))(CO)(6)] (3), and fac-[Tc(2)(20-ane-S(6)-OH)(CO)(6)][tosylate](2) (5) were isolated in good yields and characterized spectroscopically by IR, (1)H, (99)Tc NMR, and X-ray diffraction methods. In the case of 18-ane-S(6) and 20-ane-S(6)-OH the formation of the 1:2 as well as the 1:1 complex could be observed in the (99)Tc NMR experiment, depending on the ligand to metal ratio. Complex 2crystallizes in the monoclinic space group P2(1)/c, a = 14.79(2) Å, b = 11.691(2) Å, c = 16.94(2) Å, beta = 94.88(6) degrees, Z = 8. The tripodal ligand is coordinated through the sulfur atoms to the metal center, forming three favorable five-membered chelate rings. Complex 3 crystallizes in the monoclinic space group C2/c, a = 26.073(4) Å, b = 9.288(1) Å, c = 17.898(3) Å, beta = 99.84(1) degrees, Z = 4. The binuclear unit is formed by two fac-[Tc(tosylate)(CO)(3)] moieties which are trans, bidentate coordinated to the macrocyclic ligand. Compound 5 crystallizes in the monoclinic space group Pc, a = 25.737(4) Å, b = 14.009(1) Å, c = 26.479(3) Å, beta = 149.56(2) degrees, Z = 4. In the case of the dicationic compound 5, the two Tc(I) centers are tripodal, cis coordinated toward the thia crown ether. A detailed analysis of the ring conformation in the solid state structure explained to a certain extent the formation of only one isomer (trans in the case of 3 and cis in the case of 5, respectively) during the substitution reaction.

Blood cell labelling experiments were carried out with a series of 99mTc and 99m/99Tc nitridotechnetium(V) complexes containing dialkyldithiocarbamates, monoalkyldithiocarbamates or alkylxanthates as ligands. Distribution patterns of the radioactivity between plasma, erythrocytes and leukocytes/thrombocytes were determined suggesting that some of the compounds studied possess a potential as blood cell labelling agents. The chemical nature of the cell-bound technetium was found to be the intact TcN complex initially used.

TcO4− is reduced by a mixture of phosphine and thiol ligands to yield cationic complexes in which both ligands are coordinated. Polar and lipophilic properties of the products can easily be controlled by variation of either of the ligands. The yields are always high. Potential heart affinity of the compounds was screened by means of the isolated perfused rat heart. Some of the complexes show significant heart uptake and good retention in the myocardial tissue.

Es wird uber Ligandenaustauschreaktionen an den Nitridotechnetium(VI)-Komplexen (Bu4N)TcNCl4 und (Bu4N)TcNBr4 berichtet. Dabei entstehen bei Verwendung organischer Liganden mit unterschiedlichen Donoratomen Nitridokomplexe des Technetiums(V). Bei der Reaktion von (Bu4N)TcNCl4 mit (Bu4N)TcNBr4 in unterschiedlichen Mischungsverhaltnissen entstehen Komplexspezies des TcVI mit gemischter Cl/Br-Koordinationssphare. Bei Untersuchungen mittels EPR-Spektroskopie konnte fur die gebildeten Gemischtligandkomplexe eine definierte Abhangigkeit der Spektrenparameter von der Zusammensetzung der ersten Koordinationssphare nachgewiesen werden. Ligand-Exchange Reactions on TcNX4− Complexes (X = Cl, Br) Ligand exchange reactions on the nitridotechnetium(VI) compounds (Bu4N)TcNCl4 and (Bu4N)TcNBr4 are reported. The use of various organic ligands having different donor atom sets produces TcV nitrido complexes. The reaction of (Bu4N)TcNCl4 with (Bu4N)TcNBr4 is characterized by the formation of TcVI complex species with mixed Cl/Br coordination spheres. EPR detection of the mixed-ligand complexes results in a well-defined dependence of the EPR parameters on the composition of the first coordination sphere of the complexes.

A series of 7 indiumdialkyldithiocarbamates (R = ethyl, n-propyl, i-propyl, n-butyl, i-butyl, (CH 2 ) 5 , (CH 2 ) 2 O(CH 2 ) 2 ) has been prepared by reacting InCl 3 with aqueous solutions of the ligands. The products have been investigated at various concentration levels. The properties of the products at the lower concentration levels have been studied by thin-layer chromatography, electrophoresis and by determination of the octanol/water partition. A comparison of the results with the behaviour of the well-characterized tris(dialkyldithiocarbamato)indium(III) complexes is given.

Formation de complexes de l'indium(III) avec des thiocarbamates, des xanthates, des thiophosphates alkyles. Ces complexes ont ete isoles a l'etat cristallin. Donnees spectrometriques et analyse elementaire