Dicompartmental Ligands with Hexa- and Tetradentate Coordination Sites:  One-Step Synthesis of Ligands and Metal Complexes and Their X-ray Structure Analysis

1998 ◽  
Vol 37 (7) ◽  
pp. 1563-1574 ◽  
Author(s):  
Elena V. Rybak-Akimova ◽  
Nathaniel W. Alcock ◽  
Daryle H. Busch
1991 ◽  
Vol 46 (12) ◽  
pp. 1601-1608 ◽  
Author(s):  
Dieter Sellmann ◽  
Stefan Fünfgelder ◽  
Falk Knoch ◽  
Matthias Moll

In order to elucidate specific properties of nickel sulfur complexes, redox and addition-elimination reactions of [Ni(′OS4')]2, [Ni(′NHS4')]2, [Ni(′S5')], [Ni('S4—C5')], and [Ni('S4—C3')] were investigated ('OS4′ 2' = 2,2'-bis(2-mercaptophenylthio)diethylether(2—), 'NHS4'2- = 2,2'-bis(2-mercaptophenylthio)diethylamine(2—), 'S5'2- = 2,2'-bis(2-mercaptophenylthio)diethylsulfide(2—), 'S4-C5'2- = 1,5-bis(2-mercaptophenylthio)pentane(2—), 'S4—C3'2- = 1,3-bis(2-mercaptophenylthio)propane(2—)).Cyclovoltammetry proves the complexes to be redox inactive between —1.4 and +0.8 V vs. NHE. Above +0.8 V the complexes are irreversibly oxidized, below —1,4 V desalkylation takes place and [Ni(′S,′)2]2- is formed. An X-ray structure analysis was carried out of (NMe4)2[Ni(′S2')2], which shows a planar anion with the Ni center in a nearly perfect square planar coordination. Distances and angles are practically identical to those in the [Ni(′S2')2-] monoanion.The complexes coordinate only phosphines as coligands, but thioether donors simultaneously decoordinate and, dependant of reaction temperature, mono- or trisphosphine complexes are formed. [Ni(′S4—C3')(PMe3)] was characterized by X-ray structure analysis and exhibits a square pyramidal coordination geometry.


1996 ◽  
Vol 51 (4) ◽  
pp. 501-505 ◽  
Author(s):  
Wolfgang Weigand ◽  
Michael Weishäupl ◽  
Christian Robl

Abstract The 1-alkyne-1-thiolates R-C ≡C-SLi [1a: R = C(CH3)3, 1b: R = C6H11 ] react with L2PtCl2 (L = PPh3, 1/2 dppe) and CpRu(PPh3)2Cl, respectively to give the complexes trans-(Ph3P)2Pt[S-C ≡C-C(CH3)3]2 (2a), cis-dppePt[S-C≡C-C(CH3)3]2 (2b), and CpRu(PPh3)2-(S-C ≡ C-R) [3a: R = C(CH3)3, 3b: R = C6H11]. 2a has been characterized by 31P CP/MAS NM R spectroscopy and its crystal structure determined by X-ray diffraction.


2006 ◽  
Vol 61 (3-4) ◽  
pp. 263-266 ◽  
Author(s):  
Karin Schlegel ◽  
Johann Lex ◽  
Kambiz Taraz ◽  
Herbert Budzikiewicz

By X-ray structure analysis it could be shown that from the solution equilibrium of pyochelin I and II, differing in the stereochemistry at C-2″ (1a and 1b), crystals of the Fe3+ complex of the steroisomer 1a are formed with a 1:1 metal-to-ligand ratio. Ligand sites are the carboxylate and the phenolate anions and the two nitrogen atoms. Two equivalent ferri-pyochelin moieties are held together by a hydroxy and an acetate unit which satisfy the remaining two coordination sites of Fe3+.


1994 ◽  
Vol 49 (5) ◽  
pp. 660-664 ◽  
Author(s):  
Dieter Sellmann ◽  
Helge Friedrich ◽  
Falk Knoch

Attempts to coordinate N2H4 to [Fe(S2C6H4)2] fragments lead to N2H5[Fe(N2H4)(S2C6H4)2], which crystallizes from MeOH/N2H4 solutions as the solvate [(N2H5){Fe(N2H4)(S2C6H4)2} · 1,33 N2H4]. 1, and has been characterized by X-ray structure analysis. 1 contains three discrete N2H5+ cations, four N2H4 solvate molecules and three independent [Fe(N2H4)(S2C6H4)2]- anions which are connected via an extended network of N-H ··· N and N-H ··· S bridges. N2H5[Fe(N2H4)(S2ChH4)2] and 1 contain high-spin Fe(III) centers and labile N2H4 ligands.


1988 ◽  
Vol 43 (11) ◽  
pp. 1453-1460 ◽  
Author(s):  
Norbert Steiner ◽  
Ulrich Nagel ◽  
Wolfgang Beck

The preparation and spectroscopic data of the complexes cis- and trans- CL2M(NH2C(CO2Et)=C<) , (1) (M - Pd. Pt), trans-Cl2Pd(NH2CH(CH2Cl)CO2CH3)2 (2), trans- Cl2Pd(NH2CH(CH2OAc)CO2)2 (3) and trans-Cl2Pt(Gly-β-Cl-AlaOMe)2 (4) are reported. The structures of l a and 2 have been determined by X-ray structure analysis. Elimination of hydrogen chloride from 4 gives the dehydrodipeptide complex 5.


2014 ◽  
Vol 69 (5) ◽  
pp. 580-588 ◽  
Author(s):  
Dominic Schmid ◽  
Alexander Seyboldt ◽  
Doris Kunz

Upon reaction of the dipyrido-anellated guanidinium salt 1 with one equivalent of CpNa we were able to synthesize the dipyrido-anellated diaminofulvalene 4 in one step in 33% isolated yield. This shortens the initial route that applies a literature-known fulvalene synthesis via uronium salt 3 by two steps and avoids the need for a sacrificial equivalent of CpNa. Although the X-ray structure analysis reveals a shorter exocyclic double bond than observed in the diaminofulvalene V, a theoretical analysis based upon DFT calculations shows a stronger zwitterionic character for the dipyridofulvalene 4.


1989 ◽  
Vol 44 (8) ◽  
pp. 917-922 ◽  
Author(s):  
Wolf Peter Fehlhammer ◽  
Hans Hoffmeister ◽  
Borislav Boyadjiev ◽  
Thomas Kolrep

The X-ray structure analysis of (trans-4,5-dimethyloxazolidin-2-ylidene)triphenylboron reveals a stereochemistry of the carbene ligand which is almost identical with that in transition metal complexes. Deprotonation of triphenylboron stabilized oxazolidin-2-ylidenes with NaH leads to (oxazolin-2-ato)borates, which have been N-alkylated with [R3O+][BF4~] or RI under mild conditions.


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