Generation and reactivity of singlet oxygen within zeolites: remarkable control of hydroperoxidation of alkenes
作者:Rebecca J. Robbins、V. Ramamurthy
DOI:10.1039/a700977a
日期:——
A highly selective oxidation of alkenes included within a Y zeolite is
achieved by generating singlet oxygen via excitation of a
monomeric dye exchanged within a zeolite; conformational control brought
forth by the medium is suggested to be responsible for the observed
remarkable selectivity.
Selective Oxidation of Olefins within Organic Dye Cation-Exchanged Zeolites
作者:Xiaoyuan Li、V. Ramamurthy
DOI:10.1021/ja9623727
日期:1996.1.1
This paper reports selectivity in the products during single oxygen mediated oxidation of olefins included within dye-exchanged X and Y zeolites. Singlet oxygen is generated within a zeolite by irradiating a thiazine dye exchanged into zeolites. Oxazine and thiazine dye molecules can be readily exchanged for alkali cations present in the interior of faujasite (X and Y) zeolites. Depending on the status
本文报告了在染料交换 X 和 Y 沸石中包含的烯烃的单氧介导氧化过程中产物的选择性。通过辐照交换成沸石的噻嗪染料,在沸石内产生单线态氧。恶嗪和噻嗪染料分子可以很容易地与八面沸石(X 和 Y)沸石内部存在的碱性阳离子交换。根据水合状态,这些染料分子以单体或二聚体形式存在。我们在这里表明,当噻嗪染料分子以其单体形式存在于沸石中时,它可作为一种极好的单线态氧敏化剂。利用沸石超级笼作为“活性反应腔”,我们将活性氧导向烯烃的特定表面,并在氧化产物中获得高选择性。18 个参考文献,4 个无花果。
Kinetics of the Oxygenation of Unsaturated Organics with Singlet Oxygen Generated from H<sub>2</sub>O<sub>2</sub> by a Heterogeneous Molybdenum Catalyst
作者:Bert F. Sels、Dirk E. De Vos、Pierre A. Jacobs
DOI:10.1021/ja065849f
日期:2007.5.1
A heterogeneous catalyst containing MoO42- exchanged on layered double hydroxides (Mo-LDHs) is used to produce O-1(2) from H2O2, and with this dark O-1(2), unsaturated hydrocarbons are oxidized in allylic peroxides. The oxidation kinetics are studied in detail and are compared with the kinetics of oxidation by O-1(2), formed from H2O2 by a homogeneous catalyst. A model is proposed for the heterogeneously catalyzed O-1(2) generation and peroxide formation. The model divides the reaction suspension in two compartments: (1) the intralamellar and intragranular zones of the LDH catalyst; (2) the bulk solution. The 2-compartment model correctly predicts the oxidant efficiency and peroxide yield for a series of olefin peroxidation reactions. O-1(2) is generated at a high rate by the heterogeneous catalyst, but somewhat more O-1(2) is lost by quenching with the heterogeneous catalyst than using the homogeneous catalyst. Quenching occurs mainly as a result of collision with the LDH hydroxyl surface, as is evidenced by using LDH supports containing strong O-1(2) deactivators such as Ni2+. A total of 15 organic substrates were peroxidized on a preparative scale using the best Mo-LDH catalyst under optimal conditions.
BILAS, W.;HOEBOLD, W.;PRITZKOW, W., J. PRAKT. CHEM., 1982, 324, N 1, 125-141