trans-[Pd(3,5-C6Cl2F3)I(AsPh3)2] | 213135-37-6

• 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-[Pd(3,5-C6Cl2F3)I(AsPh3)2]
• 英文别名: trans-[Pd(C6Cl2F3)I(AsPh3)2]
• CAS: 213135-37-6
• 化学式: C₄₂H₃₀As₂Cl₂F₃IPd
• 分子量: 1045.77
• InChiKey: UTTIPMXYZNSQEP-UHFFFAOYSA-M

计算性质

• 辛醇/水分配系数(LogP)：
  None
• 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：
  None
• 拓扑面积：
  None
• 氢给体数：
  None
• 氢受体数：
  None

反应信息

• 作为反应物：
  描述：

  trans-[Pd(3,5-C6Cl2F3)I(AsPh3)2] 、 三丁基乙烯基锡 以 四氢呋喃 为溶剂， 生成 (Ph3As)2Pd 、 碘基三丁基锡
  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：

  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
• 作为试剂：
  描述：

  1,3-二氯-2,4,6-三氟-5-碘苯 、 三丁基(4-甲氧基苯基)锡 在 trans-[Pd(3,5-C6Cl2F3)I(AsPh3)2] copper(l) iodide 、 三苯基膦 作用下， 以 四氢呋喃 为溶剂， 生成 碘基三丁基锡 、 1,3-Dichloro-2,4,6-trifluoro-5-(4-methoxyphenyl)benzene
  参考文献：
  名称：

  Quantitative Evaluation of the Factors Contributing to the “Copper Effect” in the Stille Reaction

  摘要：

  The relative importance of the factors contributing to the accelerating effect of CuI on [PdL4]-catalyzed couplings of (RI)-I-1 and (RSnBu3)-Sn-2 (copper effect) has been quantitatively evaluated in THF for R-1 = 3,5-C6Cl2F3; R-2 = vinyl, C6H4-4-OMe; L = AsPh3, PPh3, using spectroscopic and kinetic methods. The F-19 NMR kinetic data show that the rate enhancement produced by addition of CuI is strongly related with the "autoretardation" effect intrinsic to [PdL4] catalysts and is almost independent of the organotin reagent (vinyl, aryl). The "autoretardation" is due to the release of 2 equiv of L during the oxidation of [PdL4] to yield trans-[(PdRIL2)-I-1], which is the species undergoing transmetalation. CuI does not promote the dissociation of L from trans- [(PdRIL2)-I-1], but it captures part of the free neutral ligand L and therefore mitigates the autoretardation produced by the presence of free L on the rate-determining associative transmetalation. In the conditions studied (Pd:Cu = 1:2; T = 322.6 K; THF as solvent), for L = AsPh3 the CuI added captures about 25% of the free AsPh3 and the copper effect compensates only ca. 1% of the autoretardation, whereas for L = PPh3 the CuI captures about 99% of the free PPh3 and the compensation is about 30%. This remarkable variation is caused by the combined effect of two independent factors: W The catalyst [Pd-(PPh3)](4) is more autoretarded than [Pd(AsPh3)(4)]; and (ii) CuI is a more effective scavenger for PPh3 than for AsPh3.

  DOI：

  10.1021/om020896b