Observation of the primary Zr–C insertion products in the reaction of the (butadiene)zirconocene/B(C6F5)3-betaine Ziegler catalyst system with reactive alkynes
作者:Jörn Karl、Gerhard Erker
DOI:10.1016/s1381-1169(97)00165-9
日期:1998.2
(conjugated diene) group 4 metallocenes 1a–d (diene=butadiene, isoprene; metallocene=Cp2Zr, Cp2Hf, MeCp2Zr) add B(C6F5)3 to yield the metallacyclic M⋯F–C bridged metallocene–borate–betaine complexes 3a–d. These add one equivalent of acetylene to give the chiral metallacyclic insertion products 5a–d that can be described as either intramolecular ion-pair type complexes involvinginteraction of the negatively
Reaction of diene Group 4 metallocene complexes with metal carbonyls: a novel entry to Fischer-type carbene complexes
作者:Gerhard Erker、Ulrich Dorf、Reinhard Benn、Rolf Dieter Reinhardt、Jeffrey L. Petersen
DOI:10.1021/ja00336a071
日期:1984.11
Le melange a l'equilibre (cis-/trans-η 4 -butadiene) zirconocene reagit lentement a la temperature ordinaire avec Cr(CO) 2 pour donner le complexe (zirconoxycarbene) Cr(CO) 5 . Spectres RMN et etude RX de la structure moleculaire
Le melange a l'equilibre (cis-/trans-η 4 -butadiene) zirconocene reagit lentement a la temperature ordinaire avec Cr(CO) 2 pour donner le complexe (zirconoxycarbene) Cr(CO) 5 。Specters RMN et 练习曲 RX de la结构分子
Reaction of (η4-butadiene)-zirconocene and -hafnocene with 2-methyl-2-nitrosopropane
作者:Gerhard Erker、Mark G. Humphrey
DOI:10.1016/0022-328x(89)80005-1
日期:1989.12
(η4-Butadiene)-zirconocene and -hafnocene each react with two molar equivalents of 2-methyl-2-nitrosopropane to give nine-membered metallacycles Cp2 (8a: R = t-Bu; M = Zr; 8b: R = t-Bu, M = Hf), which have a trans-carbon-carbon double bond in the ring. In solution two different dynamic processes can be observed by variable temperature NMR spectroscopy. Enantiomerization of the chiral ring system (Δent‡