trans-[Pd(3,5-C6Cl2F3)Cl(AsPh3)2] | 213135-41-2

• 英文名称: trans-[Pd(3,5-C6Cl2F3)Cl(AsPh3)2]
• 英文别名: trans-Pd(AsPh3)2(3,5-dichloro-2,4,6-trifluorophenyl)Cl
• CAS: 213135-41-2
• 化学式: C₄₂H₃₀As₂Cl₃F₃Pd
• 分子量: 954.318
• InChiKey: ZTHSTBHGTIPKLV-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-[Pd(3,5-C6Cl2F3)Cl(AsPh3)2] 、 sodium iodide 以 二氯甲烷 、 丙酮 为溶剂， 以93%的产率得到trans-[Pd(3,5-C6Cl2F3)I(AsPh3)2]
  参考文献：
  名称：

  Mechanism of the Stille Reaction. 1. The Transmetalation Step. Coupling of R¹I and R²SnBu₃ Catalyzed by trans-[PdR¹IL₂] (R¹ = C₆Cl₂F₃; R² = Vinyl, 4-Methoxyphenyl; L = AsPh₃)

  摘要：

  The so far accepted mechanism of the Stille reaction (palladium-catalyzed cross-coupling of organotin reagents with organic electrophiles) is criticized. Based on kinetic studies on catalytic reactions, and on reactions with isolated intermediates, a corrected mechanism is proposed. The couplings between (RI)-I-1 (1) (R-1 = C-6- Cl2F3 3,5-dichlorotrifluorophenyl) and (RSnBu3)-Sn-2 (R-2 = CH=CH2, 2a; C6H4-4-OCH3, 2b), catalyzed by trans-[(PdRI)-I-1(AsPh3)(2)] (3a), give R-1-R-2 and obey a first-order law, r(obs) = a[3a][2a]/(b + [AsPh3]), with a (2.31 +/- 0.09) x 10(-5) s(-1) and b = (6.9 +/- 0.3) x 10(-4) mol L-1, for [1] [2a] = 0-0.2 mol L-1, [3a] = 0-0.02 mol L-1, and [AsPh3] = 0-0.07 mol L-1, at 322.6 K in THF, The only organopalladium(II) intermediate detected under catalytic conditions is 3a. The apparent activation parameters found for the coupling of 1 with 2a support an associative transmetalation step (Delta H-obs(double dagger) = 50 +/- 2 kJ mol(-1), Delta S-obs(double dagger) = -155 +/- 7 J K-1 mol(-1) in THF; and Delta H-obs(double dagger) = 70.0 +/- 1.7 kJ mol(-1), Delta S-obs(double dagger) = -104 +/- 6 J K-l mol(-1) in chlorobenzene, with [1](0) = [2](0) = 0.2 mol L-1, [3a] = 0.01 mol L-1). The reactions of 2a with isolated trans-[PdR1 X(AsPh3)(2)] (X = halide) show rates Cl > Br > I. From these observations, the following mechanism is proposed: Oxidative addition of (RX)-X-1 to PdLn, gives cis-[(PdRXL2)-X-1], which isomerizes rapidly to trans-[(PdRXL2)-X-1]. This trans complex reacts with the organotin compound following a S-E(2)(cyclic) mechanism, with release of AsPh3 (which explains the retarding effect of the addition of L), to give a bridged intermediate [(PdRL)-L-1(mu-X)(mu-R-2)SnBu3]. In other words, an L-for-R-2 substitution on the palladium leads R-2 and R-1 to mutually cis positions. From there the elimination of XSnBu3 yields a three-coordinate species cis-[(PdRRL)-R-1-L-2], which readily gives the coupling product R-1-R-2.

  DOI：

  10.1021/ja9742388
• 作为产物：
  描述：

  、 三苯胂 以 丙酮 为溶剂， 以94%的产率得到trans-[Pd(3,5-C6Cl2F3)Cl(AsPh3)2]
  参考文献：
  名称：

  Mechanism of the Stille Reaction. 1. The Transmetalation Step. Coupling of R¹I and R²SnBu₃ Catalyzed by trans-[PdR¹IL₂] (R¹ = C₆Cl₂F₃; R² = Vinyl, 4-Methoxyphenyl; L = AsPh₃)

  摘要：

  The so far accepted mechanism of the Stille reaction (palladium-catalyzed cross-coupling of organotin reagents with organic electrophiles) is criticized. Based on kinetic studies on catalytic reactions, and on reactions with isolated intermediates, a corrected mechanism is proposed. The couplings between (RI)-I-1 (1) (R-1 = C-6- Cl2F3 3,5-dichlorotrifluorophenyl) and (RSnBu3)-Sn-2 (R-2 = CH=CH2, 2a; C6H4-4-OCH3, 2b), catalyzed by trans-[(PdRI)-I-1(AsPh3)(2)] (3a), give R-1-R-2 and obey a first-order law, r(obs) = a[3a][2a]/(b + [AsPh3]), with a (2.31 +/- 0.09) x 10(-5) s(-1) and b = (6.9 +/- 0.3) x 10(-4) mol L-1, for [1] [2a] = 0-0.2 mol L-1, [3a] = 0-0.02 mol L-1, and [AsPh3] = 0-0.07 mol L-1, at 322.6 K in THF, The only organopalladium(II) intermediate detected under catalytic conditions is 3a. The apparent activation parameters found for the coupling of 1 with 2a support an associative transmetalation step (Delta H-obs(double dagger) = 50 +/- 2 kJ mol(-1), Delta S-obs(double dagger) = -155 +/- 7 J K-1 mol(-1) in THF; and Delta H-obs(double dagger) = 70.0 +/- 1.7 kJ mol(-1), Delta S-obs(double dagger) = -104 +/- 6 J K-l mol(-1) in chlorobenzene, with [1](0) = [2](0) = 0.2 mol L-1, [3a] = 0.01 mol L-1). The reactions of 2a with isolated trans-[PdR1 X(AsPh3)(2)] (X = halide) show rates Cl > Br > I. From these observations, the following mechanism is proposed: Oxidative addition of (RX)-X-1 to PdLn, gives cis-[(PdRXL2)-X-1], which isomerizes rapidly to trans-[(PdRXL2)-X-1]. This trans complex reacts with the organotin compound following a S-E(2)(cyclic) mechanism, with release of AsPh3 (which explains the retarding effect of the addition of L), to give a bridged intermediate [(PdRL)-L-1(mu-X)(mu-R-2)SnBu3]. In other words, an L-for-R-2 substitution on the palladium leads R-2 and R-1 to mutually cis positions. From there the elimination of XSnBu3 yields a three-coordinate species cis-[(PdRRL)-R-1-L-2], which readily gives the coupling product R-1-R-2.

  DOI：

  10.1021/ja9742388

文献信息

• Strong Metallophilic Interactions in the Palladium Arylation by Gold Aryls
  作者：Mónica H. Pérez-Temprano、Juan A. Casares、Ángel R. de Lera、Rosana Álvarez、Pablo Espinet

  DOI：10.1002/anie.201108043

  日期：2012.5.14

  It's the second step that counts: Arylation of Pd by Au takes place through transition states and intermediates featuring strong Au⋅⋅⋅Pd metallophilic interactions (see picture). However, the aryl transfer from [AuArL] to [PdArClL2] is thermodynamically disfavored and will not occur unless an irreversible ArAr coupling from [PdAr2L2] follows.

  这是至关重要的第二步：Au通过过渡态和具有强Au·⋅·Pd亲金属相互作用的中间体进行Pd的钯化（见图）。然而，从[AuArL]芳转移到[PDArClL 2 ]在热力学上是不受欢迎，除非一个不可逆转的Ar不会发生氩从[PDAR联接2大号2 ]如下。
• Mechanism of the Stille Reaction. 2. Couplings of Aryl Triflates with Vinyltributyltin. Observation of Intermediates. A More Comprehensive Scheme
  作者：Arturo L. Casado、Pablo Espinet、Ana M. Gallego

  DOI：10.1021/ja001511o

  日期：2000.12.1

  The mechanism of the [PdL4]-catalyzed couplings between R-OTf (R = pentahalophenyl; L = PPh3, AsPh3) and Sn(CH=CH2)Bu-3 has been studied. The addition of LiCl favors the coupling for L = AsPh3 in THF but retards it for L = PPh3. Separate experiments show that for L = AsPhs, LiCl accelerates the otherwise very slow and rate-determining oxidative addition of the aryl triflate to [PdL4], leading to trans[PdRClL2]. Therefore, the overall process is accelerated. For L = PPh3, the rate-determining step is the transmetalation. Complex trans-[PdRXL2],with X = Cl, is formed in the presence of LiCl, whereas an equilibrium mixture mainly involving species with X = TfO, L, or S (S = solvent) is established in the absence of LiCl. Since the transmetalation is slower for X = Cl than for the other complexes, the overall process is retarded by addition of LiCl. The transmetalation in complexes trans-[PdRXL2], with X = Cl, follows the S(E)2(cyclic) mechanism proposed in Part 1 (Casado, A. L.; Espinet, P. J. Am. Chem. Sec. 1998, 120, 8978-8985), giving the coupling product R-CH=CH2 directly. For X = TfO or, L rather stable intermediates trans[PdR(CH=CH2)L-2] are detected, Supporting an SE2(open) mechanism. The I;ey:intermediates undergoing transmetalation in the conditions arid solvents most commonly used in the literature have been identified.;The operation of S(E)2(cyclic) and S(E)2(open) pathways emphasizes common aspects of the Stille reaction with the Hiyama reaction where, using (RSiF3)-Si-2 that is chiral at the alpha -carbon of R retention or inversion gt the transmetalated chiral carbon can be-induced. This helps us to understand the contradictory stereochemical outcomes in the literature for Stille couplings using (RSnR3)-Sn-2 derivatives that are chiral Bt the a-carbon of R-2 and suggests that stereocontrol of the Stille reaction might be achieved.