Green route for selective gram-scale oxidation of sulfides using tungstate/triazine-based ionic liquid immobilized on magnetic nanoparticles as a phase-transfer heterogeneous catalyst
temperature. In addition, due to the presence of ammoniumgroups in the catalyst structure, water dispersibility of the catalyst was increased. More important, the catalyst was magnetically recovered and reused for up to six runs without any marked decrease of activity and selectivity. Finally, easy gram‐scale oxidation of methylphenyl sulfide as well as fast separation of catalyst and product makes the protocol
钨离子通过阴离子交换过程成功地加载到基于三嗪的离子液体功能化的磁性纳米颗粒上。使用三嗪核生成离子液体导致了大量WO 4 2-的固定化。所得催化剂在硫化物与H 2 O 2氧化为亚砜中显示出高活性和选择性。在室温下作为绿色氧化剂。另外,由于在催化剂结构中存在铵基,因此提高了催化剂的水分散性。更重要的是,催化剂被磁性回收并重复使用多达六次,而活性和选择性均没有明显降低。最后,甲基苯硫醚易于克级氧化,以及催化剂和产物的快速分离,使得该方案经济且在工业上适用。
One-pot synthesis of symmetric 1,7-dicarbonyl compounds via a tandem radical addition–elimination–addition reaction
作者:Zhongyan Huang、Jiaxi Xu
DOI:10.1039/c3ra42932f
日期:——
A novel approach to synthesize symmetric 1,7-dicarbonyl compounds via a tandem radical additionâeliminationâaddition reaction of S-carbonylmethyl xanthates with allylmethylsulfone and its analogues has been developed. Radicals were produced from S-carbonylmethyl xanthates by adding dilauroyl peroxide and reacted with allylmethylsulfone or analogues to generate terminal olefins as intermediates. The excessive radicals reacted with the intermediate olefins immediately to give adducts of symmetric 1,7-dicarbonyl compounds. This is an efficient method to synthesize 1,7-dicarbonyl compounds under mild conditions.