71236-85-6Relevant academic research and scientific papers
FRUSTRATED LEWIS PAIR-IMPREGNATED POROUS MATERIALS AND USES THEREOF
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Page/Page column 85; 87-89, (2021/01/23)
Described herein are compositions composed of frustrated Lewis pairs impregnated in porous materials such as, for example, metal-organic frameworks, and their uses thereof. These compositions may allow new applications of frustrated Lewis pairs in catalysis by sequestering and protecting the frustrated Lewis pair within the nanospace of the porous material. Also provided are methods of hydrogenating an organic compound having at least one unsaturated functional group comprising using the compositions described herein.
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.
