165608-84-4Relevant articles and documents
On the Influence of Ligands in New Ni(0) Complexes of Disubstituted Butadiynes
Rosenthal, Uwe,Pulst, Siegmar,Arndt, Perdita,Baumann, Wolfgang,Tillack, Annegret,Kempe, Rhett
, p. 368 - 376 (2007/10/02)
It has been shown that disubstituted butadiynes react with L2Ni(C2H4) to yield mononuclear complexes L2Ni(η2(1:2)-RCC-CCR) (L = o-Tol-O)3P, R = SiMe3 (1), t-Bu (2), Ph (3).For the first time, the crystal structure of a nickel(0) alkyne complex carrying phosphite ligands (2) has been determined.The reaction of (dipy)Ni(cod) (L2 = dipy) with butadiynes R'CC-CCR is strongly influenced by the substituents of the butadiyne.With R' = R = SiMe3 (4), t-Bu (5) and Ph (6) or R' = Ph, R = SiMe3 (7) and R' = t-Bu, R = SiMe3 (8) mononuclear complexes (dipy)Ni(η2(1:2)-R'CC-CCR) have been observed.Depending on the stoichiometry with R = R' = Ph (9) and t-Bu (10) dinuclear complexes 2(μ-η2(1:2),η2(3:4)-R'CC-CCR) having two Ni atoms coordinated to two CC triple bonds were obtained.By contrast, with R' = R = SiMe3 (11), R' = t-Bu, R = SiMe3 (12) and R' = Ph, R = SiMe3 (13) the two Ni-centers were found to coordinate to the same CC triple bond to yield another type of a dinuclear complex 2(μ-η2(1:2),η2(1:2)-R'CC-CCR).Compound 5 has been characterized by X-ray crystal structure analysis.The structures of 2 and 5 are compared to that of the well-known complex (Ph3P)2Ni(η2(1:2)-t-BuCC-CCt-Bu) to study the influence of different ligands L on the structural details.In comparison to the alkyne complexes L2Ni(η2-RCCR) in butadiyne complexes of the L2Ni(η2(1:2)-R'CC-CCR) type there is only a slight effect of the different ligands.The uncomplexed CC triple bond as a part of the second substituent in conjugation to the complexed CC triple bond appears to level out the influence of ligands and substituents. - Keywords: Butadiyne, Phosphite, Dipyridyl, Crystal Structure, Nickel(0) Complexes
