Molybdenum-Tungsten Mixed-Metal Trinuclear Clusters with Two Capping Oxides and Six Bridging Acetates, and Other Mixed Molybdenum-Tungsten Clusters

Using semiempirical MNDO method of quantum chemistry the optimal geometries and corresponding electronic structures of [Pb3(OH)n]6-n model systems as well as of their hydrated [Pb3(OH)n(H2O)8-n]6-n analogues (n = 4, 5) are investigated. The most stable trinuclear lead(II) complexes present in aqueous solutions correspond to cyclo-(μ3-OH)(μ2-OH)3Pb32+, Pb(μ-OH)2Pb(μ-OH)2Pb2+, cyclo-(μ3-OH)2(μ2-OH)3Pb3+, Pb(OH)(μ-OH)2Pb(μ-OH)Pb(OH)+ and Pb(OH)(μ-OH)2Pb(μ-OH)2Pb+ systems. The key role of OH bridges (by vanishing direct Pb-Pb bonds) on the stability of individual isomers is discussed.

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Interplay between Metal Aminoalkoxides and β-Diketonates: Volatile Mixed-Metal Pr−Cu and Y−Cu Species without Fluorinated Ligands − Molecular Structures of [PrCu(η2-thd)3(μ,η2-OC2H4NMe2)2] and of [Y2(η2-thd)4{μ,η2-OCH(CH2NMe2)2}2]

European Journal of Inorganic Chemistry ◽

10.1002/(sici)1099-0682(200006)2000:6<1243::aid-ejic1243>3.3.co;2-b ◽

2000 ◽

Vol 2000 (6) ◽

pp. 1243-1252 ◽

Cited By ~ 13

Author(s):

Hervé Guillon ◽

Liliane??G. Hubert-Pfalzgraf ◽

Jacqueline Vaissermann

Keyword(s):

Molecular Structures ◽

Mixed Metal ◽

Fluorinated Ligands

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Lithium-mediated Ferration of Fluoroarenes

CHIMIA International Journal for Chemistry ◽

10.2533/chimia.2020.866 ◽

2020 ◽

Vol 74 (11) ◽

pp. 866-870

Author(s):

Lewis C. H. Maddock ◽

Alan Kennedy ◽

Eva Hevia

Keyword(s):

Hydrogen Atom ◽

Organometallic Chemistry ◽

Room Temperature ◽

Structural Elucidation ◽

Side Reactions ◽

Metal Base ◽

Lithium Amide ◽

Mixed Metal ◽

Important Challenge

While fluoroaryl fragments are ubiquitous in many pharmaceuticals, the deprotonation of fluoroarenes using organolithium bases constitutes an important challenge in polar organometallic chemistry. This has been widely attributed to the low stability of the in situ generated aryl lithium intermediates that even at –78 °C can undergo unwanted side reactions. Herein, pairing lithium amide LiHMDS (HMDS = N{SiMe3}2) with FeII(HMDS)2 enables the selective deprotonation at room temperature of pentafluorobenzene and 1,3,5-trifluorobenzene via the mixed-metal base [(dioxane)LiFe(HMDS)3] (1) (dioxane = 1,4-dioxane). Structural elucidation of the organometallic intermediates [(dioxane)Li(HMDS)2Fe(ArF)] (ArF = C6F5, 2; 1,3,5-F3-C6H2, 3) prior electrophilic interception demonstrates that these deprotonations are actually ferrations, with Fe occupying the position previously filled by a hydrogen atom. Notwithstanding, the presence of lithium is essential for the reactions to take place as Fe II (HMDS)2 on its own is completely inert towards the metallation of these substrates. Interestingly 2 and 3 are thermally stable and they do not undergo benzyne formation via LiF elimination.

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A direct solvent-free conversion approach to prepare mixed-metal metal–organic frameworks from doped metal oxides

Chemical Communications ◽

10.1039/d1cc00671a ◽

2021 ◽

Vol 57 (29) ◽

pp. 3587-3590

Author(s):

Beili Yi ◽

Haojie Zhao ◽

Yue Zhang ◽

Xiaomeng Si ◽

Guanqun Zhang ◽

...

Keyword(s):

Metal Oxides ◽

Metal Organic Frameworks ◽

Solvent Free ◽

Mixed Metal ◽

Synthesis Strategy ◽

Metal Metal ◽

Metal Organic

We propose a novel solvent-free conversion strategy of Pt–ZnO to Pt-ZIF-8. This synthesis strategy may facilitate the discovery of MMOFs that have not been reported previously.

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