Organometallic complexes alkynyl

The alkynyl-metal (metal-acetyhde) complex is one of the best building blocks for organometallic dendrimers, since it has some advantages compared to other organometallic complexes [18]. Most of the metal-acetylide complexes are thermally robust and stable, even when exposed to air and moisture. Metal-acetylide complexes are fairly accessible in high yields by well-established synthetic methodology [19]. These features are essential to the construction of dendrimers. 

McDonagh, A.M., Cifuentes, M.P., Lucas. N.T.. Humphrey, M.G., Houbrechts, S., Persoons, A. Organometallic complexes for nonhnear optics. Part 19. Syntheses and molecular quadratic hyperpolarizabilities of indoanilino-alkynyl-ruthenium complexes. J. Organomet. Chem. 605, 184-192 (2000)... 

In reactions with secondary amines containing a second nitrogen atom, the diphenylallenylidene ligand of 43 is active not only at the C -Cp double bond but also at the atom. Thus, the addition of pyrazoles to solutions of 43 leads to the pyrazolo[l,2-a]pyrazolyl complexes 85-87 (Scheme 25). Complexes 85 and 87 yield the functionalized alkynyl derivatives 88 and 89 by treatment with sodium methoxide. The formation of 85-87 involves novel 1,2,3-diheterocyclization reactions, where an organometallic complex is used for the first time [34]. 

The non-linear optical (NLO) properties of organometallic complexes have attracted significant attention over the past In this context, a series of half-sandwich alkynyl and enynyl ruthenium(ll) and osmiun(n)... 

Table XI contains data for other organometallic complexes. The chloro complexes are of interest because they were reacted with terminal alkynes to afford alkynyl complexes, and the greater nonlinearity of the alkynyl complex eompared to the sum of the precursor alkyne and chloro complex suggests the importance of electronic communication between ligated metal and alkynyl ligand. The aryl complexes have a donor-bridge-acceptor composition, but nonlinearities are...

Since the first discovery of transition metal allenylidene complexes (M=G=C=C<) in 1976, " these complexes have attracted a great deal of attention as a new type of organometallic intermediates. Among a variety of such complexes, cationic ruthenium allenylidene complexes Ru =C=C=GR R, readily available by dehydration of propargylic alcohols coordinated to an unsaturated metal center, can be regarded as stabilized propargylic cation equivalents because of the extensive contribution of the ruthenium-alkynyl resonance form... 

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