Crystal structures trinuclear complexes

Chromium, (ri6-benzene)tricarbonyl-stereochemistry nomenclature, 1,131 Chromium complexes, 3,699-948 acetylacetone complex formation, 2,386 exchange reactions, 2,380 amidines, 2,276 bridging ligands, 2,198 chelating ligands, 2,203 anionic oxo halides, 3,944 applications, 6,1014 azo dyes, 6,41 biological effects, 3,947 carbamic acid, 2,450 paddlewheel structure, 2, 451 carboxylic acids, 2,438 trinuclear, 2, 441 carcinogenicity, 3, 947 corroles, 2, 874 crystal structures, 3, 702 cyanides, 3, 703 1,4-diaza-1,3-butadiene, 2,209 1,3-diketones... 

A Au mdssbauer study of reaction products of trimeric l-benzyl-2-gold(I)-imidazole leading to Au carbene or Au imidazoline complexes and trinuclear Au " imidazolyl derivatives. X-Ray crystal structure of [ (p-l-benzylimidazolato-N, C )Au 3l2j. Journal of Organometallic Chemistry, 470, 275-283. 

When the same reaction is carried out in a 1 2 ratio the trinuclear complexes where R = C Fs (Figure 3.21) and QCI5 are obtained. The crystal structure of the former was solved by X-ray diffraction. The complex where R = QF5 can also be obtained by reaction of [AulCgFsjldppm)] with trows-[Pd(C6F5)(tht)2]... 

Ni3(2,2,2-tet)3(/u-N3)3](PF6)3 and its perchlorate analogue have been suggested as trinuclear complexes with an irregular triangle structure.2117 While a crystal structure is lacking, EXAFS and XANES spectra support the occurrence of azido-bridged trinuclear nickel(II) compounds with Ni- -Ni separations of 5.16 A and 5.12 A, respectively. Two J parameters had to be... 

The gallium and indium complexes of novel bis(thiosemicarbazones) have been investigated.71-73 Initial publications indicated a more complex stoichiometry where X-ray crystal structures suggested either dinuclear or trinuclear complexes. Whereas these complexes are quite interesting, they are less likely to result in useful nuclear medicine radiopharmaceuticals. The bis(thiosemi-carbazones) are quite useful as ligands for copper, and are discussed in more detail vide infra). 

An extension of the research on silver complexes with Lewis base-functionalized mono(A-heterocyclic carbene) ligands has been made toward the better-studied and stronger coordinating phosphine systems. The reaction of a diphenylphosphine-functionalized imidazolium salt with silver oxide in dichloromethane affords a trinuclear silver carbene complex 50, as confirmed by electrospray-ionization mass spectrometry.96,97 Metathesis reaction of 50 in methanol using silver nitrate gives 51 in 33% yield. The crystal structures of 51 were found to be different when different solvents were used during crystallization (Scheme 12).97 One NO3- anion was found to be chelated to... 

It has been several decades since oxo-centered triruthenium-carboxylate complexes with triangular cluster frameworks of Ru3(p3-0)(p-00CR)6 (R = alkyl or aryl) were first isolated [1,2]. In the early 1970s, the first oxo-centered triruthenium complex was structurally characterized by Cotton through X-ray crystal structural determination [3]. Since then, oxo-centered trinuclear ruthenium-carboxylate cluster complexes with general formula [Ru30(00CR)6(L)2L ]n+ (R = aryl or alkyl, L and... 

Fig. 25. X-ray crystal structure of trinuclear complex [Cr30(02CCH2CH3)6(H20)3]+ 107, a potential insulin mimetic. Adapted from (537).

Further condensation of the dinuclear species may occur either by continuing the edge-to-edge condensation, which leads to linear trinuclear structures such as 4a and 4b, or by condensation of a third chromium ion to each of the two chromium(III) centers in structure 2, yielding the cyclic structure 5. The (NH3)4Co(OH)2Co(CN)2(OH)2-Co(NH3)43+ cation (49) possesses structure 4a, and there is good evidence that the trinuclear amine complex Cr3(en)5(OH)45+ has the same structure (42). The linear trinuclear structure 4b has not been observed in crystal structures. The cyclic, trinuclear structure 5 has been observed in crystal structures of chromium(III) complexes with ammonia, tacn, and bispicam (40, 50, 51). 

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