11 research outputs found
A facile synthesis of 2-aryloxypyrimidine derivatives via a tandem reductive amination/intermolecular SNAr sequence*
A novel tandem reductive amination/intermolecular nucleophilic aromatic substitution (SNAr) sequence has been established for the synthesis of amine containing pyrimidine in formation of one carbon-oxygen and one carbon-nitrogen bonds in a one-pot fashion. Treatment of aldehyde with arylamine, 2-methanesulfonyl-4,6-dimethoxypyrimidine and sodium borohydride provides good overall yield. The p-toluenesulfonic acid (PTSA) can be used as activator and is generally needed in the reaction. Dioxane is the preferred reaction solvent, but reactions can also be carried out in tetrahydrofuran (THF), MeCN, toluene and dichloromethane. The procedure is carried out effectively in the presence of K2CO3. The reaction proceeds smoothly with aromatic aldehydes and arylamines possessing electron-donating or -withdrawing groups. This method can be applied to the synthesis of the oilseed rape herbicide and is superior to the classical one in several aspects: cutting out several purification steps, minimizing solvent use and chemical waste, and saving time. Its advantages such as operational convenience, high-efficient synthesis, and starting material availability make it a desirable method for preparing amines with molecular diversity and biological activity
Single-Operation Deracemization of 3H-Indolines and Tetrahydroquinolines Enabled by Phase Separation
The single-operation deracemization of 3H indolines and tetrahydroquinolines is described. An asymmetric redox approach was employed, in which a phosphoric acid catalyst, oxidant and reductant are present in the reaction mixture. The simultaneous presence of both oxidant and reductant was enabled by phase separation, and resulted in the isolation of highly enantioenriched starting materials in high yields