Magnetic magnetite nanoparticals catalyzed selective oxidation of α-hydroxy ketones with air and one-pot synthesis of benzilic acid and phenytoin derivatives
A clean and efficient protocol for selective oxidation of α-hydroxy ketones using magnetic magnetite nanoparticals (Fe3O4·MNPs) as catalyst with air as green oxidant has been developed. Application of Fe3O4·MNPs was also proved to be successful in one-pot synthesis of benzilic acid and phenytoin derivatives. The facile one-pot procedure enhanced the production efficiency, shortened the reaction time
已开发出一种清洁有效的方案,以磁性磁铁矿纳米粒子(Fe 3 O 4 ·MNPs)为催化剂,以空气为绿色氧化剂,选择性氧化α-羟基酮。Fe 3 O 4 ·MNPs在单锅合成苯甲酸和苯妥英衍生物中也被证明是成功的。简便的一锅法提高了生产效率,缩短了反应时间,并最大程度地减少了化学废物。值得注意的是,该催化剂可以重复使用至少五次,而没有任何明显的活性损失。
Metal-Free Reductive Cleavage of C−O σ-bonds in Acyloin Derivatives by an Organic Neutral Super-Electron-Donor
作者:Sylvain P. Y. Cutulic、Neil J. Findlay、Sheng-Ze Zhou、Ewan J. T. Chrystal、John A. Murphy
DOI:10.1021/jo901815t
日期:2009.11.20
Neutral organic electron-donor 7, formally a pyridinylidene carbene dimer, effects reductivecleavage of C−O σ-bonds in acyloin derivatives Ar(CO)CRR′OX (X = OAc, OPiv, OBz, OMs) and this represents the first cleavage of C−O σ-bonds by a neutral organic electron-donor. The methodology is applicable to a large array of substrates and the reduced counterparts were isolated in good to excellent yields
direct synthesis of quinoxaline derivatives via tandem N-heterocycliccarbene (NHC)-catalyzed umpolung of aldehydes/oxidation of the benzoins to benzils/condensation of benzils with benzene-1,2-diamines has been developed. A one-pot efficient and facile protocol for the direct synthesis of quinoxaline derivatives via tandem N-heterocycliccarbene (NHC)-catalyzed umpolung of aldehydes/oxidation of the
(±)Methanodibenzodiazocine tethered [C-H]δ+ functional site: Study towards benzoin condensation and Baylis-Hillman reactions
作者:ARRURI SATHYANARAYANA、GANESAN PRABUSANKAR
DOI:10.1007/s12039-015-0837-7
日期:2015.5
New heterocyclic ring systems consisting of (±) methanodibenzodiazocine and imidazolium/ benzimidazolium salts were synthesized in very good yield. Subsequently, these halide salts were subjected to the anion exchange reaction with KPF6 to yield the corresponding azolium salts in excellent yield. The possible applications of these newly prepared salts were investigated in homogeneous catalysis. Remarkable changes in the catalytic activity were observed by varying the bulkiness of N-substituent at imidazole. Catalytic activity of these newly prepared salts was tested for the benzoin condensation reaction. Exclusive formation of benzoin products were observed in good yield. Similarly, the dimerization of cyclohexen-1-one to Baylis-Hillman type product, 2-(3-oxocyclohexyl)-2-cyclohexen-1-one was studied.
The catalytic versatility of low toxicity dialkyltriazolium salts: in situ modification facilitates diametrically opposed catalysis modes in one pot
作者:Lauren Myles、Nicholas Gathergood、Stephen J. Connon
DOI:10.1039/c3cc41588k
日期:——
The ability of triazolium salts to serve as a precatalyst for both an acid and a powerful base/nucleophile (controlled by additives) has been exploited in a process characterised by a unique in situ catalyst modification strategy.