Ditungsten complexes

Dithiocarbamates, in Ru and Os half-sandwiches, 6, 493 Dithiocarbenes, Pt complexes, 8, 439 Dithiocarboxy ligands, in molybdenum carbonyls, 5, 447 Dithiolate-bridged compounds in dinuclear iron compounds with Fe-Fe bonds, 6, 238 as iron-only hydrogenase biomimetic models, 6, 239 Dithiolate diamides, with Zr(IV), 4, 784 Dithiolene—uranium complexes, synthesis and characterization, 4, 212 Ditopic receptors, characteristics, 12, 489 Ditungsten complexes, associated reactions, 5, 748 Divinyllead diacetates... 

Reaction of Mes -arsaalkyne 92 with [W(CO)sTHF] yields the antiaromatic free lA3,3A3-diarsete ditungsten complex 93 in low yield (Section 2.20.9.3) <1996CC631>. 

Ditungsten complexes If of l,2-dihydro-lA3,2A3-diphosphetes are accessible in 25-27% yield by direct [2+2] cycloaddition reactions of diphosphene ditungsten compound 82 and several alkynes at elevated temperatures <1997OM2506>. Alternatively If and related species 117 are obtained from W(CO)s-stabilized phosphirenes 119a and 119b by insertion of transient phosphinidene complex PhPW(CO)s 118a in 47% yield (Section 2.20.10) <1997OM4501>. 

A route to alkylidynes containing metals with high oxidation states involves a metathesis exchange reaction that we have referred to briefly in earlier sections of Chapter 10. Scheme 10.10 shows the triply-bonded ditungsten complex 79 reacting with either alkynes or nitriles to give the corresponding metal carbyne (path a)90 or metal-carbyne plus nitride complex (path b).91 Scheme 10.10 also shows results of molecular orbital calculations at the DFT level.92 In the case... 

The ditungsten complex, W2(C3H5)2(NMe2)4 (79), has Ci symmetry in the solid state with bridging allyl ligands that exhibit an unusual /n-jj i/j -Z-propenyl coordination mode, and the reaction of W2(OR)g with allene generates the... 

M. McCann, in Catalysis by Di- and Polynuclear Metal Cluster Complexes Catalytic Applications of Dimolybdenum and Ditungsten Complexes (Eds. R. D. Adams, F. A. Cotton), Wiley-VCH, New-York, 1998, pp. 145. 

Interaction of BHj.thf with carbyne W(CO)2(CMe )Cp at ambient temperature provides a ditungsten complex 55 containing a transverse BHEt-CMe group. The ethyl group comes from cleavage of... 

A number of reviews contain relevant material such as those on dimolybdenum and ditungsten complexes, substitution reactions of chromium complexes, the reactivity of complexes containing multiple bonds between metal atoms, model reactions of coupling ieactions2 5, and in a review principally on ruthenium chemistry.216... 

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