Two hitherto unreported sulfur-centered radicals CF SO and CF OS were generated in the gas phase through high-vacuum flash pyrolyses of sulfoxide CF S(O)X (X=CF , Cl, PhO) precursors. The CF OS molecule is the first experimental example that constitutes an oxathiyl radical. It was isolated and characterized by combining matrix-isolation IR and UV/Vis spectroscopy with quantum chemical computations up to the UCCSD(T)-F12/cc-pVTZ-F12 level of theory. Upon UV light irradiation (254 or 266 nm), sulfinyl radical (CF SO ) isomerizes to oxathiyl radical (CF OS ) in cryogenic noble gas matrices (Ar and Ne). Natural population analyses at the BP86/def2-TZVPP//UCCSD(T)-F12/cc-pVTZ-F12 level suggest that the spin density in CF OS is mainly localized on the sulfur atom (0.86), whereas, in CF SO the spin density is almost equally distributed on the sulfur (0.55) and oxygen (0.43) atoms.

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.

The formation of a built-in electric field (BIEF) can induce the electron-rich and electron-poor counterparts to synergistically modify the electronic configurations and optimize the binding strengths with intermediates, thereby leading...

Hydrogen spillover has attracted increasing interests in the field of electrocatalytic hydrogen evolution reaction (HER) in recent years because of their distinct reaction mechanism and beneficial terms for simultaneously weakening the strong hydrogen adsorption on metal and strengthening the weak hydrogen adsorption on support. By taking advantageous merits of efficient hydrogen transfer, hydrogen spillover-based binary catalysts have been widely investigated, which paves a new way for boosting the development of hydrogen production by water electrolysis. In this paper, we summarize the recent progress of this interesting field by focusing on the advanced strategies for intensifying the hydrogen spillover towards HER. In addition, the challenging issues and some perspective insights in the future development of hydrogen spillover-based electrocatalysts are also systematically discussed.

Methoxyphosphinidene oxide (CH3OPO) and isomeric methyldioxophosphorane (CH3PO2) are key intermediates in the degradation of organophosphorus compounds (OPCs). Unlike the nitrogen analogues CH3ONO and CH3NO2, the experimental data for these two prototypical OPCs are scarce. By high‐vacuum flash pyrolysis (HVFP) of the diazide CH3OP(O)(N3)2 at 1000 K, the cis and trans conformers of CH3OPO have been generated in the gas phase and subsequently isolated in cryogenic Ar and N2 matrices for IR spectroscopic characterization. Upon 266 nm laser irradiation of CH3OPO, cis→trans conformational conversion occurs with concurrent isomerization to CH3PO2. The spectroscopic identification of CH3OPO and CH3PO2 is supported by D‐, 13C‐, and 18O‐isotope labeling and quantum chemical calculations at the CCSD(T)‐F12a/cc‐pVTZ‐F12 level using configuration‐selective vibrational configuration interaction (VCI).

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N-Methylcarbamoyl azide has been characterized and the nitrene intermediate in its Curtius-rearrangement has been observed in two conformations by matrix-isolation IR and EPR spectroscopy.

Alkynyl isocyanates have been postulated as highly reactive intermediates in synthetic chemistry. Herein, the parent molecule HC≡CNCO is isolated for the first time. In sharp contrast to the previously reported short lifetime (ca. 15 s) at room temperature, we found that HC≡CNCO has a lifetime of 55 h in the gas phase (2 mbar, 300 K) with a melting point of −79.5 °C and vaporization enthalpy (ΔHvap) of 23.1(1) kJ mol−1. Apart from the IR (gas, solid, and matrix), 1H and 13C NMR, and UV/Vis spectroscopic characterization, its photoisomerization with a acylnitrene HC≡CC(O)N and cyanoketene NCC(H)CO has been observed.