An Approach to the Efficient Syntheses of Chiral Phosphino- Carboxylic Acid Esters
作者:Renta Jonathan Chew、Kristel Sepp、Bin-Bin Li、Yongxin Li、Peng-Cheng Zhu、Nguan Soon Tan、Pak-Hing Leung
DOI:10.1002/adsc.201500638
日期:2015.10.12
addition of diarylphosphines with N-enoylbenzotriazoles and analogues is described. Chiral phosphine products are obtained in 100% atom economy and without cumbersome protection–deprotection manipulations. The obtained products can be subsequently transformed to bear various functionalities, including phosphino-carboxylic esters which play critical roles in catalysis and as synthetic aids. Anti-tumour activities
nes (or NOHCs) possess structures related to N-heterocyclic carbenes (NHCs), with potentially useful applications including the stabilization of metals. In order to prepare NOHC metalcomplexes, a multi-step synthesis involving mechanochemistry, and making use of ball-milling, was designed. A library of unprecedented NHOC metalcomplexes were tested for their cytotoxic activities against HCT116 colorectal
Pyridinium 2-carboxylates decompose thermally in the presence of a variety of late transition metal precursors to yield the corresponding 2-pyridylidene-like complexes. The mild reaction conditions and structural diversity that can be generated in the heterocyclic ring make this method an attractive alternative for the synthesis of 2-pyridylidene complexes. IR spectra of the Ir(I) carbonyl compounds [IrCl(NHC)(CO)2] indicate that these N-heterocyclic carbene ligands are among the strongest σ-electron donors.
α-Cationic Arsines: Synthesis, Structure, Reactivity, and Applications
作者:Jonathan W. Dube、Yiying Zheng、Walter Thiel、Manuel Alcarazo
DOI:10.1021/jacs.6b03500
日期:2016.6.1
strongly influenced by the nature of the positively charged group. We describe the coordination chemistry of the newly prepared α-cationic arsines toward different metal centers and their reactivity in the presence of strong oxidants to afford cationic As(V) species. Their unique electronic properties have been exploited in Pt(II) catalysis to develop a new catalyst with remarkable activity in the cycloisomerization
Tri(1-adamantyl)phosphine: Expanding the Boundary of Electron-Releasing Character Available to Organophosphorus Compounds
作者:Liye Chen、Peng Ren、Brad P. Carrow
DOI:10.1021/jacs.6b03215
日期:2016.5.25
We report here the remarkable properties of PAd3, a crystalline air-stable solid accessible through a scalable SN1 reaction. Spectroscopic data reveal that PAd3, benefiting from the polarizability inherent to large hydrocarbyl groups, exhibits unexpected electron releasing character that exceeds other alkylphosphines and falls within a range dominated by N-heterocyclic carbenes. Dramatic effects in