Chromium complexes clusters

The syntheses of many Co3(CO)9X compounds from dicobalt octacarbonyl and XCCI3 have been optimized 347), and further reactions starting from 0(60)4 and XCCI3 360), or RCF —Co(CO)4 46) have been investigated in order to determine the mechanism of formation of the clusters. Methinyltricobalt enneacarbonyls are also formed from Co2(CO)g and such apical carbon precursors as acetylenes 140), dimethyl ketene 408), or carbyne chromium complexes (7 73). In several cases (7 72,... 

Aza[3]ferrocenophanes, synthesis, 6, 187 Azaheterocycles, alkynylation with Ir catalysts, 7, 340 7-Azaindole, in trinuclear Ru and Os clusters, 6, 725 Azametallacyclobutane, tantalum complexes, 5, 168 Azametallacyclopropane, with niobium, 5, 87 Aza-oxo ligands, chromium complexes, 5, 353 Azaphosphirenes, with tungsten carbonyls, 5, 623 2H-Azaphosphirenes, with tungsten carbonyls, 5, 679 Aza-titanacyclopentenes, synthesis, 4, 407-408 Azavinylidenes... 

Bis(carbodiimido) complexes, with bis-Cp Ti(IV), 4, 583 Bis(catecholato)diboron, alkyne additions, 10, 727—728 Biscorroles, in organometallic synthesis, 1, 71—72 Bis(cyclodiyne) clusters, trirutheniums and triosmiums, 6, 772 Bis(cyclooctadienyl) chromium complexes, characteristics,... 

Reactions of metal carbonyls with Zintl phases do not always yield the desired result. An example is the reaction of KSi with the metal carbonyls M(CO)6 (M = Cr, Mo, W) and the chromium complex Cr(CO)sNMe3. Instead of forming a structure with a Si4 anion, KSi reduces these transition metal compounds to form the anions, [M2(CO)io] . In addition, certain organometallic transition metal clusters have been synthesized that contain Zintl anions coordinated to the metal, but Zintl compounds are not used as the reagents. 

CF3H, Methane, trifluoro-cadmium complex, 24 55 mercury complex, 24 52 CF3NOS, Imidosulfurous difluoride, (fluorocarbonyl)-, 24 10 CH2, Methylene ruthenium complex, 25 182 CH2CI4P2, Phosphine, methylenebis-(dichloro)-, 25 121 CH3, Methyl cobalt complexes, 23 170 mercury complexes, 24 143-145 platinum complex, 25 104, lOS CNO, Cyanato silicon complex, 24 99 CN2OS2, l,3k, 2,4-Dithiadiazol-5-one, 25 53 CO, Carbon monoxide chromium complexes, 21 1, 2 23 87 cobalt complex, 25 177 cobalt, iron, osmium, and ruthenium complexes, 21 58-65 cobalt-osmium complexes 25 195-197 cobalt-ruthenium cluster complexes, 25 164... 

OC, Carbon monoxide chromium complex, 21 1, 2 chromium and tungsten complexes, 23 27 cobalt complex, 25 177 cobalt complexes, 23 15-17, 23-25 cobalt, iron, osmium, and ruthenium complexes, 21 58-65 cobalt-osmium complexes, 25 195-197 cobalt-ruthenium cluster complexes, 25 164... 

An intercalation process under reflux conditions for 4 days has been performed by Ma et al. to prepare chromium oxide-pillared manganese oxides [38]. In this reaction chromium hydroxyl acetate clusters, Cr3(OAc)7(OH)2, are used as the pillaring species. Cr + self-polymerizes under reflux to form polynuclear clusters between the manganese oxide layers. Intercalation of this trinuclear chromium complex constitutes a challenge because redox reactions may occur between manganese oxide and the transition metal oxide during the process, which could destroy the layer structure. 

Non-ionic thiourea derivatives have been used as ligands for metal complexes [63,64] as well as anionic thioureas and, in both cases, coordination in metal clusters has also been described [65,66]. Examples of mononuclear complexes of simple alkyl- or aryl-substituted thiourea monoanions, containing N,S-chelating ligands (Scheme 11), have been reported for rhodium(III) [67,68], iridium and many other transition metals, such as chromium(III), technetium(III), rhenium(V), aluminium, ruthenium, osmium, platinum [69] and palladium [70]. Many complexes with N,S-chelating monothioureas were prepared with two triphenylphosphines as substituents. 

Many carbonyl and carbonyl metallate complexes of the second and third row, in low oxidation states, are basic in nature and, for this reason, adequate intermediates for the formation of metal— metal bonds of a donor-acceptor nature. Furthermore, the structural similarity and isolobal relationship between the proton and group 11 cations has lead to the synthesis of a high number of cluster complexes with silver—metal bonds.1534"1535 Thus, silver(I) binds to ruthenium,15 1556 osmium,1557-1560 rhodium,1561,1562 iron,1563-1572 cobalt,1573 chromium, molybdenum, or tungsten,1574-1576 rhe-nium, niobium or tantalum, or nickel. Some examples are shown in Figure 17. 

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