30293-62-0Relevant academic research and scientific papers
Exclusive chemoselective reduction of imines in the coexistence of aldehydes using AuNPore catalyst
Takale, Balaram S.,Tao, Shan Mou,Yu, Xiao Qiang,Feng, Xiu Juan,Jin, Tienan,Bao, Ming,Yamamoto, Yoshinori
supporting information, p. 2558 - 2561 (2014/05/20)
Aldimines (R1HC=NR2) were reduced in the coexistence of aldehydes (R1CHO) with 100% chemoselectivity by the use of AuNPore giving corresponding amines (R1H2C-NHR2) in high chemical yields.
Platinum-catalyzed direct amination of allylic alcohols under mild conditions: Ligand and microwave effects, substrate scope, and mechanistic study
Ohshima, Takashi,Miyamoto, Yoshiki,Ipposhi, Junji,Nakahara, Yasuhito,Utsunomiya, Masaru,Mashima, Kazushi
experimental part, p. 14317 - 14328 (2010/02/16)
Transition metal-catalyzed amination of allylic compounds via a π-allylmetal intermediate is a powerful and useful method for synthesizing allylamines. Direct catalytic substitution of allylic alcohols, which forms water as the sole coproduct, has recently attracted attention for its environmental and economical advantages. Here, we describe the development of a versatile direct catalytic amination of both aryl- and alkyl-substituted allylic alcohols with various amines using Pt-Xantphos and Pt-DPEphos catalyst systems, which allows for the selective synthesis of various monoallylamines, such as the biologically active compounds Naftifine and Flunarizine, in good to high yield without need for an activator. The choice of the ligand was crucial toward achieving high catalytic activity, and we demonstrated that not only the large bite-angle but also the linker oxygen atom of the Xantphos and DPEphos ligands was highly important. In addition, microwave heating dramatically affected the catalyst activity and considerably decreased the reaction time compared with conventional heating. Furthermore, several mechanistic investigations, including 1H and 31P{1H} NMR studies; isolation and characterization of several catalytic intermediates, Pt(xantphos)Cl2, Pt(η2-C3H5OH)(xantphos), etc; confirmation of the structure of [Pt(η3-allyl)(xantphos)]OTf by X-ray crystallographic analysis; and crossover experiments, suggested that formation of the π-allylplatinum complex through the elimination of water is an irreversible rate-determining step and that the other processes in the catalytic cycle are reversible, even at room temperature.
