Jafari Mehrafshan G, Park Yerin, Pudasaini Bimal, Kurogi Takashi, Carroll Patrick J, Kaphan David M, Kropf Jeremy, Delferro Massimiliano, Baik Mu-Hyun, Mindiola Daniel J
Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA.
Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
Angew Chem Int Ed Engl. 2021 Nov 8;60(46):24411-24417. doi: 10.1002/anie.202107475. Epub 2021 Oct 7.
A low-spin and mononuclear vanadium complex, ( nacnac)V(CO)(η -P≡C Bu) (2) ( nacnac =[ArNC(CH )] CH, Ar=2,6- Pr C H ), was prepared upon treatment of the vanadium neopentylidyne complex ( nacnac)V≡C Bu(OTf) (1) with Na(OCP)(diox) (diox=1,4-dioxane), while the isoelectronic ate-complex [Na(15-crown-5)]{([ArNC(CH )]CH[C(CH )NAr])V(CO)(η -P≡C Bu)} (4), was obtained via the reaction of Na(OCP)(diox) and ([ArNC(CH )]CH[C(CH )NAr])V≡C Bu(OEt ) (3) in the presence of crown-ether. Computational studies suggest that the P-atom transfer proceeds by [2+2]-cycloaddition of the P≡C bond across the V≡C Bu moiety, followed by a reductive decarbonylation to form the V-C≡O linkage. The nature of the electronic ground state in diamagnetic complexes, 2 and 4, was further investigated both theoretically and experimentally, using a combination of density functional theory (DFT) calculations, UV/Vis and NMR spectroscopies, cyclic voltammetry, X-ray absorption spectroscopy (XAS) measurements, and comparison of salient bond metrics derived from X-ray single-crystal structural characterization. In combination, these data are consistent with a low-valent vanadium ion in complexes 2 and 4. This study represents the first example of a metathesis reaction between the P-atom of [PCO] and an alkylidyne ligand.
通过用Na(OCP)(二氧六环)（二氧六环 = 1,4 - 二氧六环）处理钒新戊炔基配合物(nacnac)V≡CBut(OTf) (1)，制备了一种低自旋单核钒配合物(nacnac)V(CO)(η -P≡CBut) (2)（nacnac = [ArNC(CH3)]2CH，Ar = 2,6 - Pr2C6H3），而等电子的酸根配合物[Na(15 - 冠 - 5)]{([ArNC(CH3)]2CH[C(CH3)NAr])V(CO)(η -P≡CBut)} (4)是在冠醚存在下，通过Na(OCP)(二氧六环)与([ArNC(CH3)]2CH[C(CH3)NAr])V≡CBut(OEt2) (3)反应得到的。计算研究表明，P原子转移是通过P≡C键跨V≡CBut部分的[2 + 2]环加成进行的，随后是还原脱羰基反应以形成V - C≡O键。使用密度泛函理论(DFT)计算、紫外/可见光谱和核磁共振光谱、循环伏安法、X射线吸收光谱(XAS)测量以及从X射线单晶结构表征得出的显著键参数比较等方法，对抗磁性配合物2和4的电子基态性质进行了进一步的理论和实验研究。综合这些数据与配合物2和4中低价钒离子一致。本研究代表了[PCO]的P原子与亚烷基炔配体之间复分解反应的第一个例子。
