Insertion reactions of alkynes into the Ru-H bond of indenylruthenium(II) hydride complexes. Mechanism of the reaction of phenylacetylene with [RuH(eta(5)-C9H7)(dppm)](dppm=bis(diphenylphosphino)methane)
Insertion reactions of alkynes into the Ru-H bond of indenylruthenium(II) hydride complexes. Mechanism of the reaction of phenylacetylene with [RuH(eta(5)-C9H7)(dppm)](dppm=bis(diphenylphosphino)methane)
复制标题
DOI：
10.1021/om970489d
复制
发表时间：
1997-12-09
期刊：
影响因子：
2.8
通讯作者：
MartinVaca, B
中科院分区：
文献类型：
--
作者：
Bassetti, M;Casellato, P;MartinVaca, B
吲哚配合物[Rux(eta(5)-C9H7)(Dppm)](dppm=双(二苯基膦)甲烷，X=H，D)与苯乙炔在甲苯中反应得到[Ru{(E)CH=CXPh}(eta(5)-C9H7)(Dppm)][RuH(eta(5)-C9H7)(Dppm)][RuH(eta(5)-C9H7)Ll‘](L=L’=PMe2Ph；L=PPh3，L=PMe2Ph；L=PPh3，L=PMe3；11‘=dppe)和[RuH(ETA(5)-Me3C9H4)(CO)(PPh3)]和环戊二烯基络合物[RuH(ETA(5)-C5H5)(Dppm)]不与PHC=CH反应，即使在更强的条件下也是如此。配合物[RuH(eta(5)-C9H7)Ll‘](Ll’=dppe；Ll‘=dppm；L=L’=PMe2Ph；L=PPh3，L‘=PMe3；L=PPh3，L‘=PMe2Ph)和吲哚取代的配合物[RuH(eta(5)-Me3C9H4)(CO)(Pr3)](Pr3=PPh3，(PPr3)-Pr-I)在二乙醚中回流反应分别得到烯基衍生物[Ru{(E)-C(CO2Me)=CH(CO2Me)}(eta(5)-C9H7)Ll’]和[Ru{(E)-C(CO2Me)=CH(CO2Me)}(eta(5)-Me3C9H4)(CO)(PR3)]，，[RuH(ETA(5)-C9H7)Ll‘]与丙酸甲酯反应生成α-金属化的烯基配合物[Ru{C(CO2Me)=CH2}(ETA(5)-C9H7)Ll’](Ll‘=dppe，dppm；L=L‘=PMe2Ph；L=PPh3，L’=PMe3)在回流乙醚中，用H-1和P-31{H-1}核磁共振谱研究了配合物RuX(eta(5)-C9H7)(Dppm)与甲苯中苯乙炔的反应动力学。该反应对Ru络合物和炔烃为一级反应。在40-60℃范围内测得的活化参数为：Delta H双匕首=17+/-2千卡摩尔(-1)，Delta S双匕首=-21+/-4卡摩尔(-1)K-1。提出了该反应的缔合机理，包括在速率控制的稳态条件下，由Ru络合物和炔生成ARM中间体，然后快速氢化物迁移和产物形成。由于类似的环戊二烯络合物[RuH(ETA(5)-C5H5)(Dppm)]缺乏反应性，该反应为吲哚效应。另一方面，吲哚和环戊二烯基络合物与活化的炔甲基丙酸酯的反应速度相当。
The indenyl complexes [RuX(eta(5)-C9H7)(dppm)] (dppm = bis(diphenylphosphino)methane, X = H, D) react with phenylacetylene to give the products of syn addition [Ru{(E)CH=CXPh}(eta(5)-C9H7)(dppm)] in toluene, in the temperature range 40-80 degrees C. The indenyl complexes [RuH(eta(5)-C9H7)LL'] (L = L' = PMe2Ph; L = PPh3, L' = PMe2Ph; L = PPh3, L' = PMe3; LL'= dppe) and [RuH(eta(5)-Me3C9H4)(CO)(PPh3)] and the cyclopentadienyl complex [RuH(eta(5)-C5H5)(dppm)] do not react with PhC=CH, even under more forcing conditions. The complexes [RuH(eta(5)-C9H7)LL'] (LL' = dppe; LL'= dppm; L = L' = PMe2Ph; L = PPh3, L' = PMe3; L = PPh3, L' = PMe2Ph) and the indenyl-substituted complexes [RuH(eta(5)-Me3C9H4)(CO)(PR3)] (PR3 = PPh3, (PPr3)-Pr-i) react with dimethyl acetylenedicarboxylate to give the alkenyl derivatives [Ru{(E)-C(CO2Me)=CH(CO2Me)}(eta(5)-C9H7)LL'] and [Ru{(E)-C(CO2Me)=CH(CO2Me)}(eta(5)-Me3C9H4)(CO)(PR3)], respectively, in diethyl ether under reflux, The reaction of [RuH(eta(5)-C9H7)LL'] with methyl propiolate yields the alpha-metalated alkenyl complexes [Ru{C(CO2Me)=CH2}(eta(5)-C9H7)LL'] (LL' = dppe, dppm; L = L' = PMe2Ph; L = PPh3, L' = PMe3) in refluxing diethyl ether, A kinetic study has been carried out for the reaction of the complexes [RuX(eta(5)-C9H7)(dppm)] with phenylacetylene in toluene, by H-1 and P-31{H-1} NMR spectroscopy. The reactions are first order with respect to the ruthenium complex and to the alkyne. The hydride and the deuteride complexes react at the same rate; intermediates are not detectable neither by kinetic studies nor by spectroscopy, The activation parameters, from rate measurements in the range 40-60 degrees C, are as follows: Delta H double dagger = 17 +/- 2 kcal mol(-1), Delta S double dagger = -21 +/- 4 cal mol(-1) K-1. An associative mechanism is proposed for the reaction, which involves the formation of arm intermediate from the ruthenium complex and the alkyne under rate-determining steady-state conditions, followed by fast hydride migration and product formation. Due to the lack of reactivity of the analogous cyclopentadienyl complex [RuH(eta(5)-C5H5)(dppm)], the reaction represents a case of indenyl effect. On the other hand, the indenyl and the cyclopentadienyl complexes react at comparable rates with the activated alkyne methyl propiolate.