1140502-97-1Relevant articles and documents
Pd-Catalyzed Aerobic Oxidation Reactions: Strategies to Increase Catalyst Lifetimes
Ho, Wilson C.,Chung, Kevin,Ingram, Andrew J.,Waymouth, Robert M.
, p. 748 - 757 (2018)
The palladium complex [(neocuproine)Pd(μ-OAc)]2[OTf]2 (1, neocuproine = 2,9-dimethyl-1,10-phenanthroline) is an effective catalyst precursor for the selective oxidation of primary and secondary alcohols, vicinal diols, polyols, and carbohydrates. Both air and benzoquinone can be used as terminal oxidants, but aerobic oxidations are accompanied by oxidative degradation of the neocuproine ligand, thus necessitating high Pd loadings. Several strategies to improve aerobic catalyst lifetimes were devised, guided by mechanistic studies of catalyst deactivation. These studies implicate a radical autoxidation mechanism initiated by H atom abstraction from the neocuproine ligand. Ligand modifications designed to retard H atom abstractions as well as the addition of sacrificial H atom donors increase catalyst lifetimes and lead to higher turnover numbers (TON) under aerobic conditions. Additional investigations revealed that the addition of benzylic hydroperoxides or styrene leads to significant increases in TON as well. Mechanistic studies suggest that benzylic hydroperoxides function as H atom donors and that styrene is effective at intercepting Pd hydrides. These strategies enabled the selective aerobic oxidation of polyols on preparative scales using as little as 0.25 mol % of Pd, a major improvement over previous work.
HYBRID IMMOLATIVE CELL-PENETRATING COMPLEXES FOR NUCLEIC ACID DELIVERY
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Paragraph 0403-0405, (2020/06/01)
There are provided herein, inter alia, complexes, compositions and methods for the delivery of nucleic acid into a cell in vivo. The complexes, compositions and methods may facilitate complexation, protection, delivery and release of oligonucleotides and polyanionic cargos into target cells, tissues, and organs both in vitro and in vivo.
Flavin Nitroalkane Oxidase Mimics Compatibility with NOx/TEMPO Catalysis: Aerobic Oxidization of Alcohols, Diols, and Ethers
Thapa, Pawan,Hazoor, Shan,Chouhan, Bikash,Vuong, Thanh Thuy,Foss, Frank W.
, p. 9096 - 9105 (2020/08/14)
Biomimetic flavin organocatalysts oxidize nitromethane to formaldehyde and NOx - providing a relatively nontoxic, noncaustic, and inexpensive source for catalytic NO2 for aerobic TEMPO oxidations of alcohols, diols, and ethers. Alcohols were oxidized to aldehydes or ketones, cyclic ethers to esters, and terminal diols to lactones. In situ trapping of NOx and formaldehyde suggest an oxidative Nef process reminiscent of flavoprotein nitroalkane oxidase reactivity, which is achieved by relatively stable 1,10-bridged flavins. The metal-free flavin/NOx/TEMPO catalytic cycles are uniquely compatible, especially compared to other Nef and NOx-generating processes, and reveal selectivity over flavin-catalyzed sulfoxide formation. Aliphatic ethers were oxidized by this method, as demonstrated by the conversion of (-)-ambroxide to (+)-sclareolide.
