| 172220-71-2

• CAS: 172220-71-2
• 化学式: C₃₃H₃₃ClNiO₄P₂
• 分子量: 649.713
• InChiKey: YMCJEHYFXDHKFP-UHFFFAOYSA-M

反应信息

• 作为产物：
  描述：

  trans-{NiCl(o-C6H4CH2P(C6H5)2)(P(CH3)2C6H5)} 、 丁炔二酸二甲酯 以 四氢呋喃 为溶剂， 以17%的产率得到
  参考文献：
  名称：

  Mechanism of the Insertion Reactions of Alkynes with Phosphanickelacycles

  摘要：

  The mechanism of the insertion reaction of substituted alkynes (PhCCPh (X), PhCCCOOEt CY), MeOOCCCCOOMe (Z)) into the Ni-C bond of trans-[{Ni(2-C(6)H(4)CH(2)PPh(2))(mu-Cl)}(2)] and trans-[NiCl(C-P)P'] (C-P = 2-C(6)H(4)CH(2)PPh(2), P' = PBz(3) (1a), PMe(2)Ph (1b); C-P = 2-C6H4-CH(2)PEt(2), P' = PBz(3) (1'a)) complexes has been investigated by means of P-31 NMR and UV-vis spectroscopy; in all cases insertion of only one molecule of alkyne has been found. The regioselectivity of the reaction is very well defined; only the regioisomer arising from a 1,2-cis addition on the Ni-C bond is obtained. The kinetics of the reactions have been studied via UV-vis spectroscopy. Results agree with the formation of a highly ordered transition state still containing the monodentate phosphine P' in its coordination sphere, the effect of the metalated phosphine being less important (for example Delta H double dagger = 43, 60, 40 kJ mol(-1) and Delta S double dagger = -118, -67, -125 J K-1 mol(-1) for the 1a + Y, 1b + Y, and 1'a + Y systems, respectively). A mechanism proceeding via the formation of a pentacoordinate intermediate aggregate, not detectable by NMR or visible spectroscopy, under the conditions of the study, is proposed. Only for the weaker Jr-acceptor alkyne PhCCPh is the observed rate constant found to be dependent on the alkyne concentration, indicating that for the other two alkynes studied the formation of the above-mentioned aggregate is complete under the kinetic conditions used (> 10-fold excess of alkyne).

  DOI：

  10.1021/om00012a023