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Given the periodic relationship of phosphines and arsines, is remodeling the catalytic asymmetric hydrophosphination reaction an efficient manner to develop the corresponding hydroarsination reaction? Herein, a chiral PCP-Pd(ii) pincer complex adept at generating enantioenriched phosphines was examined in the asymmetric hydroarsination reaction. Under distinct conditions, tertiary phosphines and arsines were generated in excellent yields (P: 96%, As: 91%) and ees (P: 90%, As: 85%). While secondary arsine reagents were not direct substitutes for the analogous phosphines, important parameters were identified which increased yield and ee of the hydroarsination reaction. Unlike the PCP-PdOAc pincer complex commonly used for hydrophosphinations, hydroarsination reactions involved a PCP-PdCl catalyst with 10 equiv. of CsF for optimal performance. Notable differences between the two reactions and their workup procedures were highlighted to guide further developments in the field. Lastly, respective mechanisms were proposed and contrasted for the activation of HEPh2 (E = P, As). [ABSTRACT FROM AUTHOR]

The impact of the structural attributes of chiral PC- and PCP-palladium catalysts was investigated in the asymmetric hydrophosphination of various heterocycle-functionalized enone substrates. Due to the architecture of the catalysts, they are confronted with potential catalyst deactivation arising from the coordination of the electron-rich heteroatoms (P, O, N and S) to the metal center. A systematic variation of the location and identity of the heteroatoms demonstrated the impact of structural modifications on the substrates, which have a significant influence on both yields (16–99%) and enantioselectivities (0–99%). A detailed discussion on the distinct catalytic mechanisms (intra- vs. inter-molecular addition) provides important information to explain the results obtained. [ABSTRACT FROM AUTHOR]

The impact of the structural attributes of chiral PC- and PCP-palladium catalysts was investigated in the asymmetric hydrophosphination of various heterocycle-functionalized enone substrates. Due to the architecture of the catalysts, they are confronted with potential catalyst deactivation arising from the coordination of the electron-rich heteroatoms (P, O, N and S) to the metal center. A systematic variation of the location and identity of the heteroatoms demonstrated the impact of structural modifications on the substrates, which have a significant influence on both yields (16–99%) and enantioselectivities (0–99%). A detailed discussion on the distinct catalytic mechanisms (intra- vs. inter-molecular addition) provides important information to explain the results obtained. [ABSTRACT FROM AUTHOR]

A 13C{1H} NMR based investigation was conducted to examine the electronic properties of C(aryl)–M bonds and their trans influence in P–C(aryl)–P pincer complexes. A series of structurally related platinum pincer complexes were rationally designed and their corresponding 13C–195Pt coupling constants were systematically examined. By methodical substitution of the ligand trans to the organometallic C(aryl)–Pt bond, this study revealed the significant influence of the ligands on the nature of the C(aryl)–M bonds. The single crystal X-ray analysis of the complexes and computational studies further confirmed the observations that the C–M bond exhibits significant π-character. [ABSTRACT FROM AUTHOR]