RIGID 5-MEMBERED AND 6-MEMBERED C,N,N'-BOUND ARYL, BENZYL, AND ALKYL ORGANOPALLADIUM COMPLEXES - SP(2) VS SP(3) C-H ACTIVATION DURING CYCLOPALLADATION AND PALLADIUM(IV) INTERMEDIATES IN OXIDATIVE ADDITION-REACTIONS WITH DIHALOGENS AND ALKYL-HALIDES
RIGID 5-MEMBERED AND 6-MEMBERED C,N,N'-BOUND ARYL, BENZYL, AND ALKYL ORGANOPALLADIUM COMPLEXES - SP(2) VS SP(3) C-H ACTIVATION DURING CYCLOPALLADATION AND PALLADIUM(IV) INTERMEDIATES IN OXIDATIVE ADDITION-REACTIONS WITH DIHALOGENS AND ALKYL-HALIDES
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DOI：
10.1021/om00029a045
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发表时间：
1993-05-01
期刊：
影响因子：
2.8
通讯作者：
VANKOTEN, G
中科院分区：
文献类型：
--
作者：
ALSTERS, PL;ENGEL, PF;VANKOTEN, G
新的Ter硝酸盐C，N，N' -Bound芳基，苄基和烷基有机丙酰辐射化合物（N，N，N'IS -CH2N（ME）CH2CCH2NME2或-CH2N（CH2CH2）2NME）通过环封层报告。 [PDI {C6H4（CH2N（ME）CH2CH2NME2）-2}]]（2C）和[PDI {CH2C6H2（CH2C6H2（CH2N（ME）CH2CH2NME2）-2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2 CH2NME2）-2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-ME2-2-ME2）（3C）（3C）（3C）（3C）已经进行了。通过合适的配体设计，palladation可以针对SP2或SP3 C-H激活，并朝着五元或六元环形成。对具有PDX2的Terdentate C，N，N'配体的BIDENATE N2部分的配位加合物的研究表明，C-H键激活可能是通过将酸阴离子（X）丢失到电子缺乏的，阳离子缺乏的，阳离子的14-电子而进行的物种[C，N，N'PDX]随后通过平面相互作用攻击分子内C-H键。 N-（2-碘苯基）-N，N'，N'，N'-三甲基乙烷-1,2-二胺（7E）的PDI2配位加合物的晶体结构显示出芳基环向金属的平面接近与指向碘原子的乙二胺单位相对于邻位位置的C-H键的中心，氢原子参与了短的非键接触这两个碘原子（3.02（2）Angstrom）和钯中心（2.97（2）Angstrom）。 2C的晶体是正骨，空间群PNAA，A = 8.5216（3）Angstrom，B = 17.6034（5）Angstrom，C = 18.8696（8）Angstrom，Z = 8，r = 0.038，对2677的反射为I> 2.5sigma， （i）和157个参数。 3C的晶体是单斜晶的，空间群P2（1）/C，A = 9.506（1）Angstrom，B = 13.582（1）Angstrom，C = 13.148（1）Angstrom，beta = 91.36（4）（4）-Degrees，Z = 4，r = 0.021对于3326个观察到I> 2.5sigma（i）和249个参数的反射。 7E的晶体是三斜晶的，空间群P1BAR，A = 8.545（1）Angstrom，B = 8.797（L）Angstrom，C = 13.829（1）Angstrom，Alpstrom，Alpha = 81.77（l） - deefees-deefees-defla，beta，beta = 75.47（l） - - （L） - - - - - - - （L） - - - （L） - - - degra学位，伽马= 63.33（l）-Degrees，z = 2，r = 2810的0.064观察到I> 2.5sigma（i）和175个参数的反射。通过H-1 NMR光谱对7E进行7E的构象分析表明，固态结构可能在很大程度上保留在溶液中。基于两个配体中的SP2/SP3 C-H激活竞争，得出的结论是，与烷基相比，这种方法可能是芳基环的普遍更轻松的。通过检测出异常稳定的有机金属PD（IV）二氯化加合物以及使用C，C， N，N'组作为氧化添加/还原性消除烷基卤化物中的观众配体。
The synthesis of new terdentate C,N,N'-bound aryl, benzyl, and alkyl organopalladium compounds (N,N' is -CH2N(Me)CH2CH2NMe2 or -CH2N(CH2CH2)2NMe) via cyclopalladation is reported. X-ray crystal structure determinations of [PdI{C6H4(CH2N(Me)CH2CH2NMe2)-2}] (2c) and [PdI{CH2C6H2(CH2N(Me)CH2CH2NMe2)-2-Me2-3,5}] (3c) have been carried out. By suitable ligand design, the palladation can be directed toward sp2 or Sp3 C-H activation and toward five-membered or six-membered ring formation. A study of coordination adducts of the bidentate N2 part of the terdentate C,N,N' ligands with PdX2 has revealed that the C-H bond activation likely proceeds via loss of an acido anion (X) to an electron-deficient, cationic 14-electron species [C,N,N'PdX] that subsequently attacks an intramolecular C-H bond via an in-plane interaction. The crystal structure of the PdI2 coordination adduct of N-(2-iodobenzyl)-N,N',N'-trimethylethane-1,2-diamine (7e) shows an oblique, above-plane approach of the aryl ring toward the metal center with the C-H bond in the ortho position with respect to the ethylenediamine unit pointing toward an iodine atom, the hydrogen atom being involved in short nonbonding contacts with both this iodine atom (3.02(2) angstrom) and the palladium center (2.97(2) angstrom). Crystals of 2c are orthorhombic, space group Pnaa, a = 8.5216(3) angstrom, b = 17.6034(5) angstrom, c = 18.8696(8) angstrom, z = 8, R = 0.038 for 2677 observed reflections with I > 2.5sigma(I) and 157 parameters. Crystals of 3c are monoclinic, space group P2(1)/c, a = 9.506(1) angstrom, b = 13.582(1) angstrom, c = 13.148(1) angstrom, beta = 91.36(4)-degrees, Z = 4, R = 0.021 for 3326 observed reflections with I > 2.5sigma(I) and 249 parameters. Crystals of 7e are triclinic, space group P1BAR, a = 8.545(1) angstrom, b = 8.797(l) angstrom, c = 13.829(1) angstrom, alpha = 81.77(l)-degrees, beta = 75.47(l)-degrees, gamma = 63.33(l)-degrees, Z = 2, R = 0.064 for 2810 observed reflections with I > 2.5sigma(I) and 175 parameters. A conformational analysis of 7e by means of H-1 NMR spectroscopy showed that the solid-state structure is likely retained to a large extent in solution. Based on sp2/sp3 C-H activation competition in two ligands, it is concluded that this approach may be responsible for the generally easier palladation of aryl rings compared to alkyl groups. The use of these rigid C,N,N'-bound palladium complexes in controlling their behavior in oxidative addition/reductive elimination reactions is exemplified by the detection of an unusually stable organometallic Pd(IV) dichloride adduct and by the use of a C,N,N' group as spectator ligand in oxidative addition/reductive elimination reactions with alkyl halides.