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471.
Dr. Matthieu Jouffroy Thi-Mo Nguyen Marie Cordier Marielle Blot Dr. Thierry Roisnel Dr. Rafael Gramage-Doria 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(36):e202201078
Direct reductive amination (DRA) is a ubiquitous reaction in organic chemistry. This transformation between a carbonyl group and an amine is most often achieved by using a super stoichiometric amount of hazardous hydride reagents, thus being incompatible with many sensitive functional groups. DRA could also be achieved by means of chemo- or biocatalysis, thereby attracting the interest of industry as well as academic laboratories due to the virtually perfect atom economy. Although DRAs are well-established for substrate pairs such as aldehydes with either 1° or 2° amines as well as ketones with 1° amines, the current methodologies are limited in the case of ketones with 2° amines. Herein, we present a general DRA protocol that overcomes this major limitation by means of iridium catalysis. The applicability of the methodology is demonstrated by accessing an unprecedented range of biologically relevant tertiary amines starting from both aliphatic ketones and aliphatic amines. The choice of a disphosphane ligand (Josiphos A or Xantphos) is essential for the success of the transformation. 相似文献
472.
Julie Aguesseau-Kondrotas Dr. Matthieu Simon Dr. Baptiste Legrand Prof. Jean-Louis Bantigniès Prof. Young Kee Kang Dr. Dan Dumitrescu Dr. Arie Van der Lee Prof. Jean-Marc Campagne Dr. Renata Marcia de Figueiredo Dr. Ludovic T. Maillard 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(30):7396-7401
As three-dimensional folding is prerequisite to biopolymer activity, complex functions may also be achieved through foldamer science. Because of the diversity of sizes, shapes and folding available with synthetic monomers, foldamer frameworks enable a numerous opportunities for designing new generations of catalysts. We herein demonstrate that heterocyclic γ-peptide scaffolds represent a versatile platform for enamine catalysis. One central feature was to determine how the catalytic activity and the transfer of chiral information might be under the control of the conformational behaviours of the oligomer. 相似文献
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