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The BH3‐mediated reduction of P‐stereogenic hydroxyalkylphosphine oxides was investigated by Density Functional Theory calculations. By combining theoretical approaches with experimental observations, we explored two mechanisms that account for its stereospecificity, implying an inversion of the configuration at the phosphorus atom. One mechanism proceeds through a cyclic intermediate in which the coordination of borane to the oxygen atoms lowers the BH3.THF‐attack barrier. However, the free energy barrier for this combined process is too high for a reaction feasible at room temperature. The calculations rather support a second mechanism that proceeds through from the same cyclic intermediate and the in‐situ formation of BH4− as reducing agent. [ABSTRACT FROM AUTHOR]

The synthesis of phosphorus molecules presenting a chiral center on the P‐atom, also known as P‐stereogenic compounds, has long attracted the curiosity of the scientific community. Indeed, these chemical compounds feature many peculiar properties, allowing their use in various fields of applications, ranging from medicine to enantioselective catalysis. However, their synthesis, and more particularly the introduction and retention of the chiral information on the phosphorus center, remains a very challenging task. That is why this review article focuses on the recent advances in the enantioselective synthesis of P‐stereogenic molecules, with a particular focus on the introduction of the chiral center on the phosphorus atom. This article summarizes the main synthetic approaches directed towards the enantioselective synthesis of such chemical entities with a historical perspective. Thus, approaches based on the use of chiral auxiliaries attached to the phosphorus atom and the use of chiral stoichiometric reagents will be discussed first, as they were historically the first to be developed. Then, the recent discoveries in the catalytic and enantioselective synthesis and the direct optical resolution of P‐chiral compounds will be discussed. [ABSTRACT FROM AUTHOR]

Proazaphosphatranes ‐Verkade's superbases‐ proved to be efficient organocatalysts for the Strecker reaction between protected imines and trimethylsilyl cyanide (TMSCN). Excellent to quantitative yields were reached and, compared to other systems, only low catalyst loading and short reaction times were required for the reaction to proceed efficiently. A remarkable initial turnover frequency (TOF), close to 105 h–1, was achieved, associated with an excellent selectivity since no side reactions were observed. A reaction mechanism was proposed and the key role played by the apical nitrogen in the proazaphosphatrane structure was demonstrated. Verkade's superbases were found to be efficient organocatalysts for the Strecker reaction, leading to high yield, in short reaction time and requiring low catalyst loading. [ABSTRACT FROM AUTHOR]

The synthesis of P,N heterobidentate phosphine / palladium complexes has been realized from P‐stereogenic enantiopure ligands. Five, six or seven membered ring complexes have been fully characterized, notably by X‐ray diffraction, allowing the study of the chelation to a "palladium (II) dichloride" unit. The nature of nitrogen coordination site as well as the size of the ring modify the bite‐angle at the solid state. Five, six or seven membered ring P,N heterobidentate phosphine / palladium complexes has been synthesized from P‐stereogenic ligands. X‐ray diffraction allowed the effect study of the nature of nitrogen coordination site as well as the size of the ring on the bite‐angle at the solid state. [ABSTRACT FROM AUTHOR]