trans-PhPd(OH)(PPh3)2 | 182749-86-6

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: trans-PhPd(OH)(PPh3)2
• 英文别名: benzene;palladium(2+);triphenylphosphane;hydroxide
• CAS: 182749-86-6
• 化学式: C₄₂H₃₆OP₂Pd
• 分子量: 725.115
• InChiKey: GKFSKFWQXXTYIC-UHFFFAOYSA-M

计算性质

• 辛醇/水分配系数(LogP)：
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• 重原子数：
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• 可旋转键数：
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• 环数：
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• sp3杂化的碳原子比例：
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• 拓扑面积：
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• 氢给体数：
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• 氢受体数：
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反应信息

• 作为反应物：
  描述：

  trans-PhPd(OH)(PPh3)2 、 4-氰基苯硼酸 以 氘代氯仿 为溶剂， 生成 trans-[{p-(CN)C6H4}PdPh(PPh3)2]
  参考文献：
  名称：

  Mechanism of the Palladium-Catalyzed Homocoupling of Arylboronic Acids:  Key Involvement of a Palladium Peroxo Complex

  摘要：

  The mechanism of the palladium-catalyzed homocoupling of arylboronic acids ArB(OH)(2) (Ar = 4-Z-C6H4 with Z = MeO, H, CN) in the presence of dioxygen, leading to symmetrical biaryls, has been fully elucidated. The peroxo complex (eta(2)-O-2)PdL2 (L = PPh3), generated in the reaction of dioxygen with the Pd(0) catalyst, was found to play a crucial role. Indeed, it reacts with the arylboronic acid to generate an adduct (coordination of one oxygen atom of the peroxo complex to the oxophilic boron atom of the arylboronic acid) characterized by P-31 NMR spectroscopy and ab initio calculations. This adduct reacts with a second molecule of arylboronic acid to generate trans-ArPd(OH)L-2 complexes. A transmetalation by the arylboronic acid gives trans-ArPdArL2 complexes. The biaryl is then released in a reductive elimination. This reaction is at the origin of the formation of biaryls as byproducts in palladium-catalyzed Suzuki-Miyaura reactions when they are not conducted under oxygen-free atmosphere.

  DOI：

  10.1021/ja0569959
• 作为产物：
  描述：

  (η2-peroxo)bis(triphenylphosphine)palladium 、 苯硼酸 以 氘代氯仿 为溶剂， 生成 trans-PhPd(OH)(PPh3)2
  参考文献：
  名称：

  Mechanism of the Palladium-Catalyzed Homocoupling of Arylboronic Acids:  Key Involvement of a Palladium Peroxo Complex

  摘要：

  The mechanism of the palladium-catalyzed homocoupling of arylboronic acids ArB(OH)(2) (Ar = 4-Z-C6H4 with Z = MeO, H, CN) in the presence of dioxygen, leading to symmetrical biaryls, has been fully elucidated. The peroxo complex (eta(2)-O-2)PdL2 (L = PPh3), generated in the reaction of dioxygen with the Pd(0) catalyst, was found to play a crucial role. Indeed, it reacts with the arylboronic acid to generate an adduct (coordination of one oxygen atom of the peroxo complex to the oxophilic boron atom of the arylboronic acid) characterized by P-31 NMR spectroscopy and ab initio calculations. This adduct reacts with a second molecule of arylboronic acid to generate trans-ArPd(OH)L-2 complexes. A transmetalation by the arylboronic acid gives trans-ArPdArL2 complexes. The biaryl is then released in a reductive elimination. This reaction is at the origin of the formation of biaryls as byproducts in palladium-catalyzed Suzuki-Miyaura reactions when they are not conducted under oxygen-free atmosphere.

  DOI：

  10.1021/ja0569959

文献信息

• Distinguishing Between Pathways for Transmetalation in Suzuki−Miyaura Reactions
  作者：Brad P. Carrow、John F. Hartwig

  DOI：10.1021/ja1108326

  日期：2011.2.23

  process and the observed rate constants for the stoichiometric reactions between the two classes of reaction components, we conclude that the reaction of a palladium hydroxo complex with boronic acid, not the reaction of a palladium halide complex with trihydroxyborate, accounts for transmetalation in catalytic Suzuki-Miyaura reactions conducted with weak base and aqueous solvent mixtures.

  我们报告了对分离的芳基钯羟基和卤化物与芳基硼酸和芳基三羟基硼酸盐的化学计量反应的系统研究，以评估通常提出的用于解释 Suzuki-Miyaura 反应中金属转移的两种反应途径的相对速率。根据在催化过程常见条件下生成的钯和有机硼物种的相对种群以及观察到的两类反应组分之间化学计量反应的速率常数，我们得出结论，钯羟基络合物与硼的反应酸，而不是卤化钯配合物与三羟基硼酸盐的反应，在用弱碱和水性溶剂混合物进行的催化 Suzuki-Miyaura 反应中解释了金属转移。