A density functional theoretical (DFT) study is presented, implicating a1O2oxidation process to reach a dihydrobenzofuran from the reaction of the natural homoallylic alcohol, glycocitrine. Our results predict an interconversion between glycocitrine and an
We report on the formation of toluidine blue O (TBO) sulfoxide by a self‐sensitized photooxidation of TBO. Here, the photo
- Award ID(s):
- 2154133
- PAR ID:
- 10479984
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Photochemistry and Photobiology
- ISSN:
- 0031-8655
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract iso ‐hydroperoxide intermediate [R(H)O+– O−] that provides a key path in the chemistry which then follows. Formations of allylic hydroperoxides are unlikely from a1O2‘ene’ reaction. Instead, the dihydrobenzofuran arises by1O2oxidation facilitated by a 16° curvature of the glycocitrine ring imposed by a pyramidalN ‐methyl group. This curvature facilitates the formation of theiso ‐hydroperoxide, which is analogous to theiso species CH2I+– I−and CHI2+– I−formed by UV photolysis of CH2I2and CHI3. Theiso ‐hydroperoxide is also structurally reminiscent of carbonyl oxides (R2C=O+– O−) formed in the reaction of carbenes and oxygen. Our DFT results point to intermolecular process, in which theiso ‐hydroperoxide's fate relates to O‐transfer and H2O dehydration reactions for new insight into the biosynthesis of dihydrobenzofuran natural products. -
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V O‐rich N‐SnO2NS) for promoting CO2conversion to HCOO−is reported. Due to the likely synergistic effect of N dopant andV O, theV O‐rich N‐SnO2NS exhibits high catalytic selectivity featured by an HCOO−Faradaic efficiency (FE) of 83% at− 0.9 V and an FE of> 90% for all C1 products (HCOO−and CO) at a wide potential range from −0.9 to− 1.2 V. Low coordination Sn–N moieties are the active sites with optimal electronic and geometric structures regulated byV Oand N dopants. Theoretical calculations elucidate that the reaction free energy of HCOO* protonation is decreased on theV O‐rich N‐SnO2NS, thus enhancing HCOO−selectivity. The weakened H* adsorption energy also inhibits the hydrogen evolution reaction, a dominant side reaction during the CO2RR. Furthermore, using the catalyst as the cathode, a spontaneous Galvanic Zn‐CO2cell and a solar‐powered electrolysis process successfully demonstrated the efficient HCOO−generation through CO2conversion and storage. -
Abstract Ru(II) complexes were synthesized with π‐expanding (phenyl, fluorenyl, phenanthrenyl, naphthalen‐1‐yl, naphthalene‐2‐yl, anthryl and pyrenyl groups) attached at a 1
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Abstract The dominant form of oxygen in cold molecular clouds is gas-phase carbon monoxide (CO) and ice-phase water (H2O). Yet, in planet-forming disks around young stars, gas-phase CO and H2O are less abundant relative to their interstellar medium values, and no other major oxygen-carrying molecules have been detected. Some astrochemical models predict that gas-phase molecular oxygen (O2) should be a major carrier of volatile oxygen in disks. We report a deep search for emission from the isotopologue16O18O (
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