Die Bildung von β-C-H agotischen Alkenylzirconocen-Komplexen bei der anormalen Hydrozirconierung von Alkinen

Article abstract of DOI:10.1016/0022-328X(88)87016-5

Some alkynes R¹CCR² bearing bulky substituents undergo abnormal hydrozirconation reactions when treated with the reagent x (1).The products obtained do not contain newly formed C-H bonds.Dicyclopentadienylzirconacyclopentadiene systems (5) are formed instead.Extended Hueckel calculations as well as the isolation of the product (3b) in addition to Cp2ZrCl2 and (5b) from Me3SiCCPh and 1 indicate that β-C-H agostic alkenylmetallocene complexes may serve as important intermediates for this variant of hydrozirconation.The molecular structure of 3b was deterrmined by an X-ray diffraction study.Complex 3b crystallizes in space group P2₁/n with cell constants a 9.641(2), b 18.066(3), c 11.762(1) Angstroem, β= 92.122(7) deg, Z=4.The Zr-C(1)-C(2) angle is 89.9 deg and the Zr-H(2) distance is 2.29(2) Angstroem.