The new bulky cyclopentadienyl anions 1,2,4-tri(cyclopentyl)cyclopentadienide and 2,3-diisopropyl-1,4-dimethyl-5-trimethylsilyl-cyclopentadienide were prepared. These and the already known 1,2,4-tri(cyclohexyl)-, 1,2,4-tri(isopropyl)-, 2,3-diisopropyl-1,4-dimethyl-, 1,3,4-triisopropyl-2,5-dimethyl-, pentaphenyl-, and p-butylphenyl-tetraphenyl-cyclopentadienide as well as tert-butylindenide were...

The organometallic tris-cyclopentadienide actinide(III) (AnCp3 ) complexes were first reported about 50 years ago. However, up until now, only the NpCp3 solid state structure has been studied. Here we report on the solid state structures of UCp3 and PuCp3 which are isostructural to the Np analogue. The structural models are supported by theoretical calculations and compared to their lanthanide ...

Reaction of chiral ester linked diynes with chlorotris(triphenylphosphine)cobalt(I) and sodium cyclopentadienide gave (η(5)-cyclopentadienyl)(triphenylphosphine) cobaltacyclopentadiene complexes as single chiral-at-metal diastereoisomers, including a non-racemic example synthesised in three steps from (S)-3-butyn-2-ol.

The synthesis of the cyclooctatetraene dianion (COT(2-)) fused at the [e]-position of trans-10b,10c-dimethyl-10b,10c-dihydropyrene (DHP) is described, and by comparison of (1)H NMR properties and NICSAv to the analogous benzene fused DHP, the relative aromaticity of the dianion is found to be at least as great as that of benzene, and substantially larger than that of the cyclopentadienide anion.

Deprotonation of 8bH-tetrabenzo[a,c,g,i]fluorene (8bH-Tbf), an extremely large benzannulated cyclopentadienyl derivative, by [NR3R'][OH] (R = (n)Bu, Et; R' = (n)Bu, Et, Bn) leads to a series of Tbf ammonium salts of the type [NR3R'][Tbf]. These cyclopentadienide analogs were smoothly isolated from a hydrous medium and structurally characterized by single X-ray diffraction. Subsequent reactions ...

The reaction of 5-(1-adamantyl)-3-methyl-1H-pyrazole with dibromomethane yields a product mixture bis(3-adamantyl-5-methylpyrazolyl)methane (H2C(PzAd,Me)2, 2 a), (3-adamantyl-5-methylpyrazolyl)-(3-methyl-5-adamantylpyrazolyl)methane ((H2C(PzAd,Me)(PzMe,Ad), b) and bis(3-methyl-5-adamantylpyrazolyl)methane (H2C(PzMe,Ad)2, c). Lithiation sterically congested H2C(PzAd,Me)2 (2 a) subsequent additio...

Cyclopentadienide (Cp) groups are among the most popular ligands in organometallic chemistry. Sterically demanding substitution patterns on Cp ring can have an important effect ligand properties and there many examples of metal complex which only stable isolatable with sterically ligands, carrying alkyl or aryl groups. Among these pentaisopropylcyclopentadienide is bulkiest pentaalkyl derivativ...

Cyclopentadienyl nickel com plexes [(C 5 H 2rBu3 -l,2 ,4)N i(M -C O ) ] 2 (1) and [(C 5 H/Pr4 )N i(//-C O ) ] 2 (2) have been synthesized from nickel tetracarbonyl and the corre­ sponding lithium cyclopentadienide, and [(C 5 /Pr5 )N i(//-C O ) ] 2 (3) has been obtained in high yield from nickel tetracarbonyl and the free pentaisopropylcyclopentadienyl radical. The crystal structure o f 1 shows ...