journal article Dec 01, 2007

Mechanism of Ethylene Oligomerization by a Cationic Palladium(II) Alkyl Complex that Contains a (3,5-Me2-pyrazolyl)2CHSi(p-tolyl)3) Ligand

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References
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The four ethylene hydrogens comprise an ABCD system under slow rotation conditions, and an AA′BB′ system under fast rotation conditions.
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The oligomerization distribution produced by5at 30 atm of ethylene fit a Shultz−Flory distribution (α = 0.35 and β = 1.8). However, oligomerizations at 2.7 atm of ethylene pressure did not produce Shultz−Flory distributions.
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The compound [1H][B(C6F5)4] was generated quantitatively by the reaction of1(10 mg, 20 µmol) and [H(OEt2)2][B(C6F5)4] (16 mg, 20 µmol) in CD2Cl2(0.7 mL) for 10 min at 25 °C.1H NMR (CD2Cl2, 25 °C): δ 12.63 (br s, 1H, H+), 7.24 (m, 12 H, 4-Me-C6H4), 6.50 (s, 1H, CH), 6.06 (s, 2H, pz* H4), 2.39 (s, 9H, 4-Me-C6H4), 2.21 (s, 3H, pz* Me), 2.05 (s, 3H, pz* Me). ESI-MS: [(pz*)2CHSi(p-tolyl)3]H+calcdm/z505.2, found 505.2. [1H][B(C6F5)4] decomposes in CD2Cl2solution at 25 °C (ca. 25% after 24 h).
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Published
Dec 01, 2007
Vol/Issue
26(27)
Pages
6750-6759
Cite This Article
Matthew P. Conley, Christopher T. Burns, Richard F. Jordan (2007). Mechanism of Ethylene Oligomerization by a Cationic Palladium(II) Alkyl Complex that Contains a (3,5-Me2-pyrazolyl)2CHSi(p-tolyl)3) Ligand. Organometallics, 26(27), 6750-6759. https://doi.org/10.1021/om7007698