Synthesis and structure of 1-zirconacyclopent-3-yne complexes without substituents adjacent to the triple bond.
Five-membered metallacyclic alkynes that have no substituents adjacent to the triple bond have been synthesized, isolated, and structurally characterized. Zirconocene dichlorides, Cp'2ZrCl2 (Cp' = C5H5, C5H4-t-Bu), reacted with 1,4-dichlorobut-2-yne in the presence of magnesium to give 1-zirconacyclopent-3-yne compounds (5 (a) Cp' = C5H5, (b) Cp' = C5H4-t-Bu) that have a -CH2CCCH2- moiety in good yields. They are stable enough to be isolated in a pure form, despite the absence of substituents. 5a reacted with an equimolar amount of Cp2Zr(but-1-ene)(PMe3) to produce a bimetallic complex in which the zirconacyclopentyne coordinates to the other zirconocene moiety as an alkyne.
Suzuki
Noriyuki
N
RIKEN, Wako, Saitama 351-0198, Japan. nsuzuki@riken.jp
Aihara
Naoto
N
Takahara
Hidemichi
H
Watanabe
Takaaki
T
Iwasaki
Masakazu
M
Saburi
Masahiko
M
Hashizume
Daisuke
D
Chihara
Teiji
T