Zirconium acetylides

An extension of the original methodology has seen the synthesis of propargylic alcohols in moderate to good yields from silver acetylides via zirconium acetylides (Scheme 1.45).108... [Pg.25]

The mono- and di-alkali metal acetylides, copper acetylides, iron, uranium and zirconium carbides all ignite in chlorine, the former often at ambient temperature. See Caesium acetylide Halogens Dicopper(I) acetylide Halogens Iron carbide Halogens... [Pg.1408]

Lithium acetylide Halogens Monocaesium acetylide Monorubidium acetylide Strontium acetylide Halogens Uranium dicarbide Halogens Zirconium dicarbide Halogens See Monolithium acetylide-ammonia Gases... [Pg.1409]

Monocaesium acetylide and caesium acetylide, lithium acetylide and rubidimn acetylide, tungsten carbide and ditungsten carbide, and zirconium dicarbide all ignite in cold fluorine, while uranium dicarbide ignites in warm fluorine. [Pg.1516]

Lead(II) oxide tungsten, zirconium Chlorinated rubber, chlorine, ethylene, fluorine, glycerol, metal acetylides, perchloric acid... [Pg.1478]

Zinc Acetylide A83 L Zinc Azide A624-L Zinc Azidodithiocarbonate A637-L Zinc Diazide A624-L Zirconium Carbide A83-L i... [Pg.692]

MICHAEL ADDITIONS Alumina. Aluminum chloride. Cesium fluoride-Silicon(lV) cthoxidc. 1,4-Diazabicyclo[2.2.2]octanc. l,8-Diazabicyclo[5.4.0]-7-undecene. Ketene r-butyldimethylsilyl methyl acetal. Lithium acetylides. (S)-( + )-2-Mcthoxymethylpyrrolidine. Methyl lithiodithioacetate. Methyl (phcnylsulfinyl)acetate. Methyl 2-trimcthylsilylacrylate. Nickel carbonyl. Organocopper reagents. 8-Phenylmcnthol. Phenyl 2-(trimethylsilyl)ethynyl sulfone. Tetra-n-butylammonium fluoride. Tiianium(IV) chloride. 3-Triisopropylsilylpropynyllithiuni. Zirconium(IV) n-propoxiilc... [Pg.648]

Several of the mono- and di-alkali metal acetylides and copper acetylides ignite at ambient temperature or on slight warming, with either liquid or vapour. The alkaline earth, iron, uranium and zirconium carbides ignite in the vapour on heating. [Pg.119]

Tetraamminelithium dihydrogenphosphide, 4590 Thorium dicarbide, 1023 Titanium carbide, 0558 Trimercury tetraphosphide, 4611 Tungsten carbide, 0560 Uranium carbide, 0559 Uranium dicarbide, 1024 Zinc phosphide, 4870 Zirconium dicarbide, 1025 METAL ACETYLIDES N-METAL DERIVATIVES METAL HYDRIDES METAL OXIDES METAL SULFIDES NITRIDES... [Pg.2438]

Zirconium trichloride, 4154 Zirconium(II) chloride, 4115 COMPLEX HYDRIDES METAL ACETYLIDES METAL HYDRIDES... [Pg.2568]

Silver acetylides participate in the zirconium-catalyzed nucleophilic addition to carbonyls in the absence of base to produce functionalized y - h yd ro x y - a, [3 - ac e t y I e n i c esters.106 Although this reaction involves a transmetallation rather than a direct addition of a silver acetylide to an unactivated aldehyde, its particular attraction of is the avoidance of strong bases to produce the reactive zirconium species (Scheme 1.43). [Pg.25]

In the nucleophilic opening of oxiranes by silver acetylides (see Section 10.4), Koide et al. provided good evidence for transmetallation of silver acetylides to dichlorozirconocene leading to alkynyl zirconium species.98... [Pg.314]

Terminal alkyne complexes of zirconium, while challenging to isolate, have been implicated in a number of organometallic transformations. Mixing an alkenyl zirconocene 218 with a transient dialkyl zirconocene 111 furnishes a yu-acetylide complex 219 (Scheme 33).112 This reaction is believed to proceed by initial transmetallation to form a zirconocene alkenyl alkyl 220, which undergoes subsequent /3-hydrogen abstraction to generate the terminal alkyne complex 221. This proposed intermediate can be trapped with PMe3 222 from the alkylation of the zirconocene alkenyl bromide with butyllithium. Comparison of the spectroscopic features of this product to the... [Pg.719]

Zirconocene complexes 705 that contain an acetylide ligand bridging between a main group metal (aluminum) and a transition metal (zirconium) are obtained by treatment of dimethyl zirconocene with (alkynyl)dimethylaluminum, (Equation (43)).529 In this reaction, an ( 72-alkyne)zirconocene complex is presumably formed in situ, and it is then trapped by the excess (alkynyl)dimethylaluminum to yield the final product. The molecular structures of the complexes 705 (R = SiMe3, Cy) contain a dimetallabicyclic framework, and one of the bridgehead positions is a planar tetracoordinate carbon center. In these complexes, the -C=CR bridge between zirconium and aluminum can be described as being mainly of /x-(cr-acetylide) character. [Pg.895]

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