Controlling P–C/C–H Bond Cleavage in Nickel Bis(diphosphine) Complexes: Reactivity Scope, Mechanism, and Computations
Controlling P–C/C–H Bond Cleavage in Nickel Bis(diphosphine) Complexes: Reactivity Scope, Mechanism, and Computations
复制标题
控制镍双(二膦)络合物中的 P-C/C-H 键断裂:反应范围、机制和计算
DOI:
10.1021/acs.organomet.0c00388
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发表时间:
2020
期刊:
影响因子:
2.8
通讯作者:
Bullock, R. Morris
中科院分区:
文献类型:
--
作者:
Zhang, Shaoguang;Li, Haixia;Appel, Aaron M.;Hall, Michael B.;Bullock, R. Morris
The synthesis of heteroleptic [Ni(P2N2)(diphosphine)][BF4]2complexes and the cleavage of P–C and C–H bonds of the P2N2ligand in those complexes are reported. The products are five-coordinate complexes in which Ni–C and P–H bonds have formed to give a cyclic moiety containing Ni–CH═NR2. The reactivity of [Ni(P2N2)(diphosphine)][BF4]2complexes is influenced by the rigidity of the diphosphine, the steric effect of the substituents, and length of the carbon linker of the diphosphine ligands. Diphosphine ligands bearing a rigid backbone (e.g., dmpbz, 1,2-bis(dimethylphosphino)benzene) or aromatic substituents (e.g., dppe, 1,2-bis(diphenylphosphino)ethane) react with [Ni(PtBu2NBn2)(CH3CN)2][BF4]2to give P–C/C–H bond cleavage products. Both [Ni(PtBu2NBn2)(dmpe)(MeCN)][BF4]2and [Ni(PtBu2NBn2)(dmpm)(MeCN)][BF4]2(dmpm = 1,2-bis(dimethylylphosphino)methane) were prepared by the reaction of [Ni(PtBu2NBn2)(CH3CN)2][BF4]2with the corresponding diphosphine ligands. [Ni(PtBu2NBn2)(dmpe)(MeCN)][BF4]2readily undergoes P–C/C–H bond cleavage in nitromethane. In sharp contrast, [Ni(PtBu2NBn2)(dmpm)][BF4]2is stabilized by dmpm, a diphosphine with small bite angle, and does not show P–C/C–H bond cleavage reactivity. Computational results show that for complexes bearing less bulky diphosphine ligands, such as dmpm, the barriers for the rate-determining transition states are in some examples higher than 30 kcal/mol with the M06 functional, higher than those for complexes bearing more rigid or more bulky ligands, consistent with experimental studies. The calculated barriers for the first transition state correlated with increased values of the dihedral angle formed by the two NiP2planes.
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影响因子:
4.6
作者:
Heiden, Zachariah M.;Chen, Shentan;Bullock, R. Morris
通讯作者:
Bullock, R. Morris
DOI:
--
发表时间:
1997
期刊:
影响因子:
--
作者:
M. Hirano;Masato Akita;Takashi Morikita;Hiroaki Kubo;A. Fukuoka;S. Komiya
通讯作者:
S. Komiya
DOI:
--
发表时间:
2012
期刊:
影响因子:
--
作者:
Candace S. Seu;A. Appel;Michael D. Doud;D. Dubois;C. Kubiak
通讯作者:
C. Kubiak
影响因子:
--
作者:
Shaoguang Zhang;Haixia Li;A. Appel;M. Hall;R. Bullock
通讯作者:
R. Bullock
影响因子:
2.8
作者:
Eric S. Wiedner;Jenny Y. Yang;W. Dougherty;W. Kassel;R. Bullock;M. Dubois;D. Dubois
通讯作者:
D. Dubois