Methoxyphosphinidene and Isomeric Methylphosphinidene Oxide

Abstract

A rare oxyphosphinidene (MeOP) has been generated in the triplet ground state through either photolysis (266 nm) or flash-vacuum pyrolysis (FVP, 700 °C) of methoxydiazidophosphine MeOP­(N3)2. Upon ArF laser irradiation (193 nm), an unprecedented isomerization from MeOP to the long-sought methylphosphinidene oxide (MePO) occurs in cryogenic Ne- and N2-matrices. Alternatively, the latter can be efficiently generated through photolysis (193 nm) or FVP (ca. 700 °C) of methylphosphoryl diazide MeP­(O)­(N3)2, in which the elusive nitrene intermediate MeP­(O)­(N3)N in the triplet ground state has been also observed by IR (with 15N-labeling) and EPR (|D/hc| = 1.545 cm–1 and |E/hc| = 0.003 95 cm–1) spectroscopy.

Phosphorus Analogues of Methyl Nitrite and Nitromethane: CH3OPO and CH3PO2

“…The former exhibits a small negative D ‐isotopic shift of −5.5 cm −1 but a negligible 13 C‐shift (<0.5 cm −1 ) and unexpectedly, it splits into two components at 1245.2 and 1232.5 cm −1 in cis ‐CH 3 18 OPO (Figure S2). In line with the electronegativity of the substituents F>CH 3 O>CH 3 , the frequency for ν(P=O) in CH 3 OPO (1238.8 cm −1 ) is between those of FPO (1292.5 cm −1 , Ar matrix) and CH 3 PO (1194.7 cm −1 , Ne matrix) . No IR band for the isotopomer cis ‐CH 3 OP 18 O was observed when CH 3 18 OP(O)(N 3 ) 2 was used as the precursor.…”

“…In contrast to the isomerization between nitro compound RNO 2 and nitrite RONO, no isomerization for PhPO 2 (→PhOPO) was observed. Continuing the increasing interest in the fundamental chemistry of small low‐valent phosphorus compounds such as HPCO/HOCP, HC≡P, CH 3 OP/CH 3 PO, R−P=S, Me 2 N−P, R 2 C=CH−P, and H 2 NC(O)PH 2 /HC(O)PMe 2 , herein, we report the first synthesis of CH 3 OPO in cis and trans conformations through high‐vacuum flash pyrolysis (HVFP) of phosphoryl diazide CH 3 OP(O)(N 3 ) 2 . In addition to the conformational conversion of CH 3 OPO and its isomerization to CH 3 PO 2 , the elusive nitrene intermediate CH 3 OP(O)(N 3 )N in the decomposition of the diazide has also been observed (Scheme ).…”

“…Comparing to the IR spectrum of the precursor (Figure A), nearly 80 % of the azide decomposes with formation of several new species. Among the pyrolysis products, the presence of H 2 CO (f, 2797.6, 1740.1, and 1496.2 cm −1 ), HOPO (g, 3518.4, 1248.3, and 865.0 cm −1 ), H 2 O (h, 3727.1 and 1597.3 cm −1 ), and HN 3 (i, 3321.9 and 2149.4 cm −1 , Figure B) implies the simultaneous decomposition of the hydrolysis product CH 3 OP(O)(OH) 2 (→ HOPO + H 2 CO + H 2 O, Figure S1) in the azide sample (CH 3 OP(O)(N 3 ) 2 + 2 H 2 O → CH 3 OP(O)(OH) 2 + 2 HN 3 ).…”

Isolation and Characterization of the Free Phenylphosphinidene Chalcogenides C6H5P=O and C6H5P=S, the Phosphorous Analogues of Nitrosobenzene and Thionitrosobenzene

“…The heavier congener H−P=S has been detected with neutralization–reionization mass spectrometry and rotational spectroscopy . Only in 2019, CH 3 −P=O was generated and efficiently trapped in argon matrices through photolysis or flash vacuum pyrolysis of methylphosphoryl diazide CH 3 P(O)(N 3 ) 2 …”

Photolysis of PCl3/POCl3 with Oxygen Dopant Using 193 nm ArF Excimer at Low Temperatures: Oxygen Insertion through ‘Phosphadioxirane’ Pathway

“…Recently, Zeng and co‐workers reported the production of a rare oxyphosphinidene from methylphosphoryl diazide through 193 nm photo irradiation in N 2 and Ne matrixes. Alternately, the same oxyphosphinidene was reported to be generated via the generation of oxyphosphinidene from 266 nm photolysis of methoxydiazidophosphine, followed by 193 nm excitation . Furthermore, an elusive 16‐electron triatomic cyclic PON ring was generated through the photolysis of OPN in low temperature N 2 matrix .…”