Photoinduced oxidation of triphenylphosphine isolated in a low-temperature oxygen matrix

Abstract

a b s t r a c tPhotooxidation reactions of triphenylphosphine (Ph 3 P) monomers isolated in matrices of solid oxygen at 10 K were characterized by means of infrared spectroscopy. Upon UV (k > 280 nm) irradiation of O 2 matrices, ca. 90% of Ph 3 P was converted to triphenylphosphine oxide (Ph 3 P@O), with concomitant formation of ozone. In the competing photoreaction, ca. 10% of Ph 3 P was converted to diphenyl-phenyl-phosphinate, Ph 2 (PhÀOÀ)P@O. The interpretation was assisted by theoretical [DFT(B3LYP)/6-31G(d, p)] calculations of vibrational spectra, as well as by comparison with the experimental vibrational data from separate experiments in which monomeric Ph 3 P and Ph 3 P@O were isolated in argon and oxygen matrices at 10 K.

Phosphine oxides as NMR and IR spectroscopic probes for the estimation of the geometry and energy of PO⋯H–A hydrogen bonds

“…[50][51][52] The 31 P is a sensitive spin-1/2 nucleus with a large span of chemical shifts, [53][54][55] which are informative in the case of non-covalent interactions, [56][57][58][59] while the stretching vibrations of the PQO group lead to characteristic bands in the IR spectra. [60][61][62][63] The relatively large span of 31 P NMR chemical shift changes of phosphine oxides due to their complexation (up to 75 ppm) was used previously to characterize the electron acceptor properties of solvents 64 and other compounds exhibiting Lewis acidity 65,66 (the so-called Gutmann-Beckett scale of acceptor numbers AN), and new papers on this subject keep appearing from time to time, 58,67,68 including one comprehensive review. 69 The first report on using 31 P NMR of phosphine oxides for hydrogen bond characterization was published in 1982.…”

31P NMR Evidence for Peroxide Intermediates in Lipid Emulsion Photooxidations: Phosphine Substituent Effects in Trapping

“…Bulky electron‐rich phosphines such as sSPhos 1 are ligands for Suzuki–Miyaura cross‐coupling reactions in the field of organic synthesis, facilitating C–C, C–N and C–O bond formations . Organic solvent soluble phosphines are highly oxophilic and trap oxygen from peroxide sources . These processes include phosphorus biphilic insertion to obtain phosphorane intermediates .…”

Measuring Cumulative Exposure to Oxygen with a Diphenylphosphine–Alkyl Naphthaleneimide Luminescence Turn‐On Dyad

“…[12] This reaction is known to be photocatalyzed by both UV and visible light. [13] Electronic-energy calculations also identified two major conformers for the phosphine oxide 5,w hich have the naphthaleneimide and phosphine oxide in gauche and anti conformations across the ethylene bridge. Here, the gauche conformer is more stable than the anti conformer by 0.029 eV (0.673 kcal mol À1 )i nt he gas phase,whereas in ethanol the anti and gauche conformers have virtually the same energy [anti is more stable than gauche by 0.001 eV (0.026 kcal mol À1 )].T he phosphine oxide no longer has the NB P: lone-pair orbital, and the HOMO of the phosphine system is located below the HOMO NI level by À0.231 eV (anti), À0.641 eV (gauche)a nd À0.588 eV (anti), À0.614 eV (gauche)i nt he gas phase and in ethanol respectively ( Figure 1).…”