Yang Chengbo, Jiang Xuebin, Chen Qi, Leng Xuebing, Xiao Jie, Ye Shengfa, Deng Liang
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China.
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Dalian 116023, China.
J Am Chem Soc. 2022 Nov 16;144(45):20785-20796. doi: 10.1021/jacs.2c08647. Epub 2022 Nov 2.
White phosphorus activation with low-valent metal species has proved to be very effective in converting P into small P-containing molecules with ≤ 4. Much less developed are metal-mediated P-coupling reactions that can yield selectively large polyphosphorus clusters. Herein, we report P-activation reactions with three-coordinate -heterocyclic carbene(NHC)-cobalt(0)-alkene complexes, which produce the P complexes of cobalt [(NHC)Co(μ-η:η-P)] (NHC = 1,3-dimesitylimidazol-2-ylidene (IMes), ; 1,3-bis(2,6-diethylphenyl)imidazol-2-ylidene (IDep), ) in high yields. The P ligand in and exhibits a signet-ring type structure that was predicted by theoretical study but has never been obtained in synthetic molecules. Theoretical studies suggest that [(NHC)Co(μ-η:η-P)] is best described as a Co-[P]-Co complex featuring a Co-Co σ-bond and discernible Co-to-P back-donation. By treating with -heterocyclic silylene, phosphinidene precursor, organic azides, and NHCs, complex was transformed into [(IMes)Co(μ-η:η-PX)] (X = 1,3-bis(-butyl)-1,3-diaza-2-silacyclopent-4-en-2-ylidene, ; PNMe, ), [(IMes)Co(σ:(μ-η:η)-RNPPP)] (R = SO-CH--Me, ; C(CF)Ph, ), and [(IMes)Co(μ-η:η-PP(IPr))(μ-η:η-P)] (), respectively. Complexes - can be viewed as the adducts of with the corresponding carbene analogous SiR, PR, NR, and CR, but their core structures are distinct. Under similar conditions, white phosphorus is inert toward these reagents. These cage functionalization reactions showcase the enhanced reactivity of the P ligand in [(NHC)Co(μ-η:η-P)] over that of P, and indicate the amphiphilicity of the P ligand toward electrophiles and nucleophiles.
事实证明，用低价金属物种活化白磷在将磷转化为含磷小分子（磷原子数≤4）方面非常有效。而能够选择性地生成大型多磷簇的金属介导的磷偶联反应则发展得少得多。在此，我们报道了三配位的 - 杂环卡宾（NHC）- 钴（0）- 烯烃配合物的磷活化反应，该反应能高产率地生成钴的磷配合物[(NHC)Co(μ-η:η-P)]（NHC = 1,3 - 二甲基咪唑 - 2 - 亚基（IMes）；1,3 - 双（2,6 - 二乙基苯基）咪唑 - 2 - 亚基（IDep））。 和 中的磷配体呈现出一种理论研究预测的但从未在合成分子中得到过的印戒型结构。理论研究表明，[(NHC)Co(μ-η:η-P)]最好被描述为一种具有Co - Co σ键和明显的Co到P的反馈π键的Co - [P] - Co配合物。通过用杂环硅烯、磷烯前体、有机叠氮化物和NHC处理，配合物 分别转化为[(IMes)Co(μ-η:η-PX)]（X = 1,3 - 双（- 丁基）- 1,3 - 二氮杂 - 2 - 硅杂环戊 - 4 - 烯 - 2 - 亚基；PNMe）、[(IMes)Co(σ:(μ-η:η)-RNPPP)]（R = SO - CH - - Me；C(CF)Ph）和[(IMes)Co(μ-η:η-PP(IPr))(μ-η:η-P)]（）。配合物 - 可被视为 与相应卡宾类似物SiR、PR、NR和CR的加合物，但其核心结构不同。在类似条件下，白磷对这些试剂是惰性的。这些笼状官能化反应展示了[(NHC)Co(μ-η:η-P)]中磷配体相对于磷的增强的反应活性，并表明了磷配体对亲电试剂和亲核试剂的两亲性。
