Andrea, Kori A. published the artcileIron Complexes for Cyclic Carbonate and Polycarbonate Formation: Selectivity Control from Ligand Design and Metal-Center Geometry, Application of 4-Hydroxy-3-tert-butylanisole, the main research area is aminobisphenolate iron complex preparation crystal mol structure; cyclic carbonate preparation; carbon dioxide reaction epoxide aminobisphenolate iron complex catalyzed.
A family of 17 iron(III) aminobis(phenolate) complexes possessing different phenolate substituents, coordination geometries, and donor arrangements were used as catalysts for the reaction of carbon dioxide (CO2) with epoxides. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of the iron complexes with a bis(triphenylphosphine)iminium chloride cocatalyst in neg. mode revealed the formation of six-coordinate iron “”ate”” species. Under low catalyst loadings (0.025 mol % Fe and 0.1 mol % chloride cocatalyst), all complexes showed good-to-excellent activity for converting propylene oxide to propylene carbonate under 20 bar of CO2. The most active complex possessed electron-withdrawing dichlorophenolate groups and for a 2 h reaction time gave a turnover frequency of 1240 h-1. Epichlorohydrin, styrene oxide, Ph glycidyl ether, and allyl glycidyl ether could also be transformed to their resp. cyclic carbonates with good-to-excellent conversions. Selectivity for polycarbonate formation was observed using cyclohexene oxide, where the best activity was displayed by trigonal-bipyramidal iron(III) complexes having electron-rich phenolate groups and sterically unencumbering tertiary amino donors. Those containing bulky tertiary amino ligands or those with square-pyramidal geometries around iron showed no activity for polycarbonate formation. While the overall conversions declined with decreasing CO2 pressure, CO2 incorporation remained high, giving a completely alternating copolymer. The difference in the optimum catalyst reactivity for cyclic carbonate vs. polycarbonate formation is particularly noteworthy; i.e., electron-withdrawing-group-containing phenolates give the most active catalysts for propylene carbonate formation, whereas catalysts with electron-donating-group-containing phenolates are the most active for polycyclohexene carbonate formation. This study demonstrates that the highly modifiable aminophenolate ligands can be tailored to yield iron complexes for both CO2/epoxide coupling and ring-opening copolymerization activity.
Inorganic Chemistry published new progress about Crystal structure. 121-00-6 belongs to class ethers-buliding-blocks, name is 4-Hydroxy-3-tert-butylanisole, and the molecular formula is C11H16O2, Application of 4-Hydroxy-3-tert-butylanisole.
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem