3041-16-5Relevant articles and documents
Method for preparing P-dioxanone from diethylene glycol and catalyst thereof
-
Paragraph 0047-0075, (2021/05/01)
The invention relates to the technical field of organic catalytic synthesis, in particular to a method for preparing p-dioxanone from diethylene glycol and a catalyst thereof. The method comprise the following steps of reacting the diethylene glycol under the action of the catalyst to generate the p-dioxanone, wherein the catalyst is a supported metal catalyst in which an active metal component is supported on a hydroxyapatite carrier. The method can be carried out in a green solvent or under a solvent-free condition, and p-dioxanone can be prepared from diethylene glycol at a conversion rate of up to 100%; moreover, the reaction process for preparing p-dioxanone from diethylene glycol is simple, the equipment is simple, the operation is simple and convenient, and the reaction conditions are very mild; meanwhile, the preparation process of the catalyst is simple, the cost is low, large-scale production can be realized, the thermal stability of the catalyst is high, and the recycling performance is good; reaction products, catalysts and solvent systems are easy to separate, reaction period is short, and the method is suitable for industrial production.
(Cyclopentadienone)iron-Catalyzed Transfer Dehydrogenation of Symmetrical and Unsymmetrical Diols to Lactones
Tang, Yidan,Meador, Rowan I. L.,Malinchak, Casina T.,Harrison, Emily E.,McCaskey, Kimberly A.,Hempel, Melanie C.,Funk, Timothy W.
, p. 1823 - 1834 (2020/02/04)
Air-stable iron carbonyl compounds bearing cyclopentadienone ligands with varying substitution were explored as catalysts in dehydrogenative diol lactonization reactions using acetone as both the solvent and hydrogen acceptor. Two catalysts with trimethylsilyl groups in the 2- A nd 5-positions, [2,5-(SiMe3)2-3,4-(CH2)4(δ4-C4C= O)]Fe(CO)3 (1) and [2,5-(SiMe3)2-3,4-(CH2)3(δ4-C4C= O)]Fe(CO)3 (2), were found to be the most active, with 2 being the most selective in the lactonization of diols containing both primary and secondary alcohols. Lactones containing five-, six-, and seven-membered rings were successfully synthesized, and no over-oxidations to carboxylic acids were detected. The lactonization of unsymmetrical diols containing two primary alcohols occurred with catalyst 1, but selectivity was low based on alcohol electronics and modest based on alcohol sterics. Evidence for a transfer dehydrogenation mechanism was found, and insight into the origin of selectivity in the lactonization of 1°/2° diols was obtained. Additionally, spectroscopic evidence for a trimethylamine-ligated iron species formed in solution during the reaction was discovered.
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.
