A fluoroaryl substituent with spectator function: Reactivity and structures of cyclic and acyclic HF4C6-substituted phosphanes

Azido-Functionalized Aromatic Phosphonate Esters in RPOSS-Cage-Supported Lanthanide Ion (Ln = La, Nd, Dy, Er) Coordination

Within this work, a modified preparation of diethyl 4-azidobenzylphosphonate (L1) is presented and the family of 4- or 4'-azido-substituted aromatic phosphonate esters is increased by three new ligand platforms: diisopropyl 4-azidobenzylphosphonate (L2), diisopropyl ((4'-azido-[1,1'-biphenyl]-4-yl)methyl)phosphonate (L3), and diisopropyl 4-azido-2,3,5,6-tetrafluorobenzylphosphonate (L4), which exhibit an anomalous splitting of the N₃ stretching vibrations. Subsequent coordination to the in situ generated ^RPOSS (polyhedral oligomeric silsesquioxane)-cage-supported lanthanide precursors [(Ln{^RPOSS})₂(THF)_m] (P1-P6) (Ln = La, Nd, Dy, Er; R = iBu, Ph; m = 0, 1) yields complexes of the general formula [Ln{^RPOSS}(L1-L4)_n(S1)_x(THF)_m] (1-30) (n = 2, 3; x = 0, 1; m = 0-2) retaining the azide unit for future semiconductor surface immobilization. Because the latter compounds are mostly oils or viscous waxes, preliminary solution-state structure elucidations via DOSY-ECC-MW estimations have been carried out which are in accordance with ¹H NMR integral ratios as well as solid-state structures, where available. Moreover, the optical properties of the Nd, Dy, and Er derivatives of complexes 1-30 are examined in the visible and NIR spectral regions, where applicable.

Functionalised phosphonate ester supported lanthanide (Ln = La, Nd, Dy, Er) complexes

A series of electronically diverse phosphonate ester ligands is synthesized and coordinated to La, Nd, Dy and Er ions for which their luminescence properties in the visible and NIR spectral regions are investigated.

P-C bond formation via P-H addition of a fluoroaryl phosphinic acid to ketones

The synthesis, structure and reactivity of the fluoroaryl phosphinic acid HF₄C₆–P(O)HOH is reported and compared to a sterically comparable yet non-fluorinated analog with similar size. The fluoroaryl phosphinic acid undergoes reversible P–H addition to the carbonyl functionality of ketones under formation of a P–C bond which is retained in the resulting α-hydroxy phosphinic acid. The latter shows an extended 2D hydrogen bonded network in the solid state.

Computational and experimental approaches to the molecular structure of the HCl adduct of Me3PO

The reaction of anhydrous HCl(g) with trimethyl phosphane oxide yields trimethylhydroxy phosphonium chloride. A crystal structure analysis showed that the prevalent mesomeric structure in the solid state is the phosphonium chloride ion pair. Ab initio calculations in the gas phase cannot reproduce these findings, whereas higher correlated methods (CISD) and solvation models predict the experimental structure correctly.