6284-14-6Relevant articles and documents
A comprehensive examination of the self-disproportionation of enantiomers (SDE) of chiral amides via achiral, laboratory-routine, gravity-driven column chromatography
Suzuki, Yuya,Han, Jianlin,Kitagawa, Osamu,Acea, Jos Luis,Klika, Karel D.,Soloshonok, Vadim A.
, p. 2988 - 2993 (2015)
This work explores the self-disproportionation of enantiomers (SDE) of chiral amides via achiral, gravity-driven column chromatography as typically used in laboratory settings. The major findings of this work are: (1) the remarkable persistence and high magnitude of the SDE for the analytes under a variety of conditions, including polar solvents and different achiral stationary phases and (2) the notable generality of the SDE phenomenon as it occurs for a wide range of chiral amide substrates and even for a broad range of starting ee. This last aspect is unusual and not commonly observed. The key conclusion of this work is that it judiciously conveys the predictability of the SDE for chiral amides under the routine conditions of achiral chromatography. These results are consequently of concern for practitioners in the area of catalytic asymmetric synthesis involving chiral amides as intermediates or products and the inferents need to be taken extremely seriously by workers in the field.
Decarboxylative cross-nucleophile coupling via ligand-to-metal charge transfer photoexcitation of Cu(ii) carboxylates
Li, Qi Yukki,Gockel, Samuel N.,Lutovsky, Grace A.,DeGlopper, Kimberly S.,Baldwin, Neil J.,Bundesmann, Mark W.,Tucker, Joseph W.,Bagley, Scott W.,Yoon, Tehshik P.
, p. 94 - 99 (2022/01/11)
Reactions that enable carbon–nitrogen, carbon–oxygen and carbon–carbon bond formation lie at the heart of synthetic chemistry. However, substrate prefunctionalization is often needed to effect such transformations without forcing reaction conditions. The development of direct coupling methods for abundant feedstock chemicals is therefore highly desirable for the rapid construction of complex molecular scaffolds. Here we report a copper-mediated, net-oxidative decarboxylative coupling of carboxylic acids with diverse nucleophiles under visible-light irradiation. Preliminary mechanistic studies suggest that the relevant chromophore in this reaction is a Cu(ii) carboxylate species assembled in situ. We propose that visible-light excitation to a ligand-to-metal charge transfer (LMCT) state results in a radical decarboxylation process that initiates the oxidative cross-coupling. The reaction is applicable to a wide variety of coupling partners, including complex drug molecules, suggesting that this strategy for cross-nucleophile coupling would facilitate rapid compound library synthesis for the discovery of new pharmaceutical agents. [Figure not available: see fulltext.].
Preparation and catalytic evaluation of a palladium catalyst deposited over modified clinoptilolite (Pd&at;MCP) for chemoselective N-formylation and N-acylation of amines
Amirsoleimani, Mina,Khalilzadeh, Mohammad A.,Zareyee, Daryoush
, (2020/08/22)
Novel palladium nanoparticles stabilized by clinoptilolite as a natural inexpensive zeolite prepared and used for N-formylation and N-acylation of amines at room temperature at environmentally benign reaction conditions in good to excellent yields. Pd (II) was immobilized on the surface of clinoptilolite via facile multi-step amine functionalization to obtain a sustainable, recoverable, and highly active nano-catalyst. The structural and morphological characterizations of the catalyst carried out using XRD, FT-IR, BET and TEM techniques. Moreover, the catalyst is easily recovered using simple filtration and reused for 7 consecutive runs without any loss in activity.