Synthesis and structural characterisation of new ansa -bis(propene)s and ansa -bis(allyl) alkali metal and ansa -bis(allyl) transition metal complexes
journal contribution
posted on 2023-06-07, 22:17authored byRafael Fernandez Galan, Peter B Hitchcock, Michael F Lappert, Antonio Antinolo, Ana M Rodriguez
The new ansa-bis(propene)s, R2Si(CH2CH[double bond, length half m-dash]CHSiR'3)2 (R = R' = Me 1; R = Ph, R' = Me 2; R = R' = Ph 3; R = Me, R' = Ph 4; R = Me, R' = Me2But5) have been prepared by lithiation of the appropriate 3-silylpropene and quenching with SiCl2R2 (R = Me or Ph). The ?3-ansa-bis(allyllithium) compounds [{Li(tmen)}2{3-(?3-C3H3SiR'3-1)2}SiR2] (R = R' = Me 6; R = Ph, R' = Me 7; R = R' = Ph 8; R = Me, R' = Ph 9; R = Me, R' = Me2But10) complexes were obtained from of the appropriate ansa-bis(propene) and LiBun. The lithium complex 6 was transformed into the potassium complex [K2{3-(?3-C3H3SiMe3-1)2SiMe2}] 11 and into [Hf{3-(?3-C3H3SiMe3-1)2SiMe2}2] 13 by reaction with KOBut or HfCl4, respectively. From 11 and ZrCl4 [Zr{3-(?3-C3H3SiMe3-1)2SiMe2}2] 12 was obtained. Single crystal X-ray structures of complexes 4, 6 and 12 are presented. Complex 12, in presence of methylaluminoxane (MAO), was an active catalyst for the polymerisation of ethylene.
History
Publication status
Published
Journal
Journal of the Chemical Society, Dalton Transactions