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Tungsten carbonyl complexes synthesis

A tungsten carbonyl complex of the 1-cyanophosphole has also been used with success in the synthesis of other P-substituted complexes (e.g. the P—OH complex (296) see below). [Pg.848]

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... [Pg.60]

FT-ICR, see Fourier-transform ion cyclotron resonance Fullerene[60], germanium-germanium addition, 10, 748 Fullerenes with cobalt, 7, 51 on cobalt Cp rings, 7, 73 inside metallodendrimers, 12, 401 microwave applications, 1, 334 Pd rc-complexes, 8, 348 Ru—Os complexes, 6, 830 with tungsten carbonyls, 5, 687 )2-Fullerenes, with platinum, 8, 634 Fulvalene actinide complex, synthesis, 4, 232 Fulvalene chromium carbonyls, synthesis and characteristics, 5, 264... [Pg.107]

Heterometal alkoxide precursors, for ceramics, 12, 60-61 Heterometal chalcogenides, synthesis, 12, 62 Heterometal cubanes, as metal-organic precursor, 12, 39 Heterometallic alkenes, with platinum, 8, 639 Heterometallic alkynes, with platinum, models, 8, 650 Heterometallic clusters as heterogeneous catalyst precursors, 12, 767 in homogeneous catalysis, 12, 761 with Ni—M and Ni-C cr-bonded complexes, 8, 115 Heterometallic complexes with arene chromium carbonyls, 5, 259 bridged chromium isonitriles, 5, 274 with cyclopentadienyl hydride niobium moieties, 5, 72 with ruthenium—osmium, overview, 6, 1045—1116 with tungsten carbonyls, 5, 702 Heterometallic dimers, palladium complexes, 8, 210 Heterometallic iron-containing compounds cluster compounds, 6, 331 dinuclear compounds, 6, 319 overview, 6, 319-352... [Pg.118]

Imidazolium ligands, in Rh complexes, 7, 126 Imidazolium salts iridium binding, 7, 349 in silver(I) carbene synthesis, 2, 206 Imidazol-2-ylidene carbenes, with tungsten carbonyls, 5, 678 (Imidazol-2-ylidene)gold(I) complexes, preparation, 2, 289 Imidazopyridine, in trinuclear Ru and Os clusters, 6, 727 Imidazo[l,2-a]-pyridines, iodo-substituted, in Grignard reagent preparation, 9, 37—38 Imido alkyl complexes, with tantalum, 5, 118—120 Imido-amido half-sandwich compounds, with tantalum, 5,183 /13-Imido clusters, with trinuclear Ru clusters, 6, 733 Imido complexes with bis-Gp Ti, 4, 579 with monoalkyl Ti(IV), 4, 336 with mono-Gp Ti(IV), 4, 419 with Ru half-sandwiches, 6, 519—520 with tantalum, 5, 110 with titanium(IV) dialkyls, 4, 352 with titanocenes, 4, 566 with tungsten... [Pg.125]

The photochemical synthesis of the tungsten carbonyl metallocarborane [Eq. (18) ] is also effective in the preparation of the molybdenum carbonyl analog. The resulting air-sensitive complexes show chemical behavior similar to the cyclopentadienyl analogs, C5H5M(CO)3, in that they undergo protonation with anhydrous HOI and met.hylation with CH3I. They also react further with metal hexacarbonyls to afford bimetallic complexes 54) ... [Pg.165]

In addition to cationic cyclizations, other conditions for the cyclization of polyenes and of ene-ynes to steroids have been investigated. Oxidative free-radical cyclizations of polyenes produce steroid nuclei with exquisite stereocontrol. For example, treatment of (259) and (260) with Mn(III) and Cu(II) afford the D-homo-5a-androstane-3-ones (261) and (262), respectively, in approximately 30% yield. In this cyclization, seven asymmetric centers are established in one chemical step (226,227). Another intramolecular cyclization reaction of iodo-ene poly-ynes was reported using a carbopaUadation cascade terminated by carbonylation. This carbometalation—carbonylation cascade using CO at 111 kPa (1.1 atm) at 70°C converted an acycHc iodo—tetra-yne (263) to a D-homo-steroid nucleus (264) [162878-44-6] in approximately 80% yield in one chemical step (228). Intramolecular aimulations between two alkynes and a chromium or tungsten carbene complex have been examined for the formation of a variety of different fiised-ring systems. A tandem Diels-Alder—two-alkyne annulation of a triynylcarbene complex demonstrated the feasibiHty of this strategy for the synthesis of steroid nuclei. Complex (265) was prepared in two steps from commercially available materials. Treatment of (265) with Danishefsky s diene in CH CN at room temperature under an atmosphere of carbon monoxide (101.3 kPa = 1 atm), followed by heating the reaction mixture to 110°C, provided (266) in 62% yield (TBS = tert — butyldimethylsilyl). In a second experiment, a sequential Diels-Alder—two-alkyne annulation of triynylcarbene complex (267) afforded a nonaromatic steroid nucleus (269) in approximately 50% overall yield from the acycHc precursors (229). [Pg.442]

The direct synthesis of chrysanthemic acid was accomplished by the reaction of a tungsten carbonyl carbene complex 28 with senecio acid 77 [41] (Reaction scheme 18). [Pg.10]

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. [Pg.988]


See other pages where Tungsten carbonyl complexes synthesis is mentioned: [Pg.12]    [Pg.151]    [Pg.12]    [Pg.442]    [Pg.127]    [Pg.289]    [Pg.54]    [Pg.56]    [Pg.68]    [Pg.96]    [Pg.121]    [Pg.126]    [Pg.164]    [Pg.168]    [Pg.168]    [Pg.2814]    [Pg.4047]    [Pg.4983]    [Pg.125]    [Pg.442]    [Pg.2813]    [Pg.4046]    [Pg.4982]    [Pg.335]    [Pg.152]    [Pg.150]    [Pg.171]    [Pg.145]    [Pg.35]    [Pg.86]    [Pg.68]    [Pg.368]   
See also in sourсe #XX -- [ Pg.5 ]




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