Bis-alkynyl complexes

Although the Lewis basicity of the nitrogen atom of imines is weak, the bis-alkynyl complex Os(C2Ph)2(CO)(P Pr3)2 also coordinates benzophenone imine to give the six-coordinate bis-alkynyl complex Os(C2Ph)2(CO)(NH=CPh2)(PI Pr3)2,... 

The hydride-methyl complex OsH(Me)(CO)2(P Pr3)2 reacts with electrophilic reagents. The reaction products depend on the nature of the reagent (Scheme 39). Whereas the reaction with iodine gives almost quantitatively the diiodide OsI2(CO)2(P,Pr3)2, the reaction with a five-fold excess of phenylacetylene does not lead to the formation of the previously mentioned bis-alkynyl complex... 

A number of stable heterobimetallic copper alkyne complexes have been reported, based on the strategy of using another metal bis(alkynyl) complex as a chelating ligand for copper. The 1,4-diyne [(r -CsFGSiMe Ti-(C=GSiMe3)2]180 (or related complex) was found to stabilize the copper units GuX, with X = alkyl,180,181 vinyl,180... 

In the alkyne chemistry described previously, combination of bis-alkynyl complexes with a second metal complex gives the tweezer complex, which may... 

Bis(alkyl) complexes, with mercury, preparation, 2, 428 Bis(alkylidene)s, in Ru and Os half-sandwiches, 6, 583 Bis(alkylimido) complexes, with chromium(VI), 5, 346 Bis(rj2-alkyne)platinum(0) complexes, preparation, 8, 640 Bis(alkynyl) complexes in [5+2+l + l]-cycloadditions, 10, 643 with manganese, 5, 819 with mercury, preparation, 2, 426 mononuclear Ru and Os compounds, 6, 409 with platinum, 12, 125 with platinum(II), 8, 539 with titanium(IV), 4, 643 with zirconium, 4, 722... 

For ruthenium catalysts a detailed study of [(PP3)RuH2] proposes a bis(alkynyl) complex as the real catalyst. The catalytic key step involves the protonation of an alkynyl ligand by external PhC=CH, allowing subsequent C-C bond formation between cis vinylidene and alkynyl groups [9]. 

A series of luminescent mercury(II) bis(alkynyl) complexes containing oligothiophenes have been synthesized by Wong via direct merciuation of the corresponding alkynes (see equation S). Most importantly, the optical properties of these species have been found to be easily tuned by modifying the... 

A M-N M = Ti, Zr, Hf Formed from bis-alkynyl complexes, products contain peripheral cyclopropenium rings as well as heterorings 1999JOM115... 

Cp(CO)2Fe-C=CR (R = H, Ph, Bu, C=CH) and Cp (CO)2Fe-C=CH concluded that alkynyl-to-metal n donation is significant and destabilises the metal d levels due to filled-filled interactions, while metal-to-ligand 7i backdonation is very weak." " The same overall picture obviously applies to bis(alkynyl) complexes C=CR)2(PR3)2 of palladium and platinum. Application of... 

A series of alkynyl complexes TpRu(C=CR)Cl(NO) were prepared by Onishi et al. from TpRuCl2(NO) and an excess of terminal alkynes in the presence of NEts (Scheme 21)."° If the same reaction is performed with ethynylbenzene in the presence of Cul as catalyst, the novel bis(alkynyl) complex TpRu(C=CPh)2(NO) was obtained. " Upon treatment of these cr-acetylide complexes with one equivalent of H2O in the presence of HBF4 Et20 in distilled MeOH several compounds were obtained in good yields including ketonyl, bisketonyl, acyl and metallacyclopente-none complexes. 

Cubic NLO data for selected group 10 metal bis(alkynyl) complexes are listed in Table XVII. Hyperpolarizability decreases progressing down the group for phe-nylalkynyl examples, the same observation as with group 4 metal alkynyl complexes (see above). For these complexes is, in all cases, close to 3co, and a high-order intensity dependence was observed this is characteristic of multiphoton resonant enhancement, so it is possible that three-photon effects exist. 

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