75-28-5Relevant articles and documents
Rational Preparation of Well-Defined Multinuclear Iridium-Aluminum Polyhydride Clusters and Comparative Reactivity
Camp, Clément,Del Rosal, Iker,Escomel, Léon,Jeanneau, Erwann,Maron, Laurent,Robin, Emmanuel,Soulé, Na?me,Thieuleux, Chloé
, (2022/02/10)
We report an original alkane elimination approach, entailing the protonolysis of triisobutylaluminum by the acidic hydrides from Cp*IrH4. This strategy allows access to a series of well-defined tri- and tetranuclear iridium aluminum polyhydride clusters, depending on the stoichiometry: [Cp*IrH3Al(iBu)2]2(1), [Cp*IrH2Al(iBu)]2(2), [(Cp*IrH3)2Al(iBu)] (3), and [(Cp*IrH3)3Al] (4). Contrary to most transition-metal aluminohydride complexes, which can be considered as [AlHx+3]x-aluminates and LnM+moieties, the situation here is reversed: These complexes have original structures that are best described as [Cp*IrHx]n-iridate units surrounding cationic Al(III) fragments. This is corroborated by reactivity studies, which show that the hydrides are always retained at the iridium sites and that the [Cp*IrH3]-moieties are labile and can be transmetalated to yield potassium ([KIrCp*H3], 8) or silver (([AgIrCp*H3]n, 10) derivatives of potential synthetic interest. DFT calculations show that the bonding situation can vary in these systems, from 3-center 2-electron hydride-bridged Lewis adducts of the form Ir-H←Al to direct polarized metal-metal interaction from donation of d-electrons of Ir to the Al metal, and both types of interactions take place to some extent in each of these clusters.
Decarbonylative ether dissection by iridium pincer complexes
Yoo, Changho,Dodge, Henry M.,Farquhar, Alexandra H.,Gardner, Kristen E.,Miller, Alexander J.M.
, p. 12130 - 12138 (2020/11/26)
A unique chain-rupturing transformation that converts an ether functionality into two hydrocarbyl units and carbon monoxide is reported, mediated by iridium(i) complexes supported by aminophenylphosphinite (NCOP) pincer ligands. The decarbonylation, which involves the cleavage of one C-C bond, one C-O bond, and two C-H bonds, along with formation of two new C-H bonds, was serendipitously discovered upon dehydrochlorination of an iridium(iii) complex containing an aza-18-crown-6 ether macrocycle. Intramolecular cleavage of macrocyclic and acyclic ethers was also found in analogous complexes featuring aza-15-crown-5 ether or bis(2-methoxyethyl)amino groups. Intermolecular decarbonylation of cyclic and linear ethers was observed when diethylaminophenylphosphinite iridium(i) dinitrogen or norbornene complexes were employed. Mechanistic studies reveal the nature of key intermediates along a pathway involving initial iridium(i)-mediated double C-H bond activation. This journal is
PREPARATION METHOD FOR PREPARING A CATALYST BASED ON IRON NANOPARTICLES, COBALT NANOPARTICLES OR ALLOYS THEREOF, THE CATALYST THUS PREPARED AND USE OF THE CATALYST FOR THE SELECTIVE HYDROGENATION OF CARBON DIOXIDE TO ISOBUTANE
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Page/Page column 14-15; 17-18, (2020/06/19)
The present invention describes a preparation method for preparing a catalyst made up of a Fe and Co metal alloy in several ratios in the form of nanoparticles embedded in a graphitic carbon matrix. Another object of the invention is also the prepared catalyst which in a surprising manner selectively catalyses the hydrogenation of carbon dioxide into isobutane.
