13816-33-6Relevant articles and documents
On the Nature of C(sp3)-C(sp2) Bond Formation in Nickel-Catalyzed Tertiary Radical Cross-Couplings: A Case Study of Ni/Photoredox Catalytic Cross-Coupling of Alkyl Radicals and Aryl Halides
Badir, Shorouk O.,Gutierrez, Osvaldo,Molander, Gary A.,Song, Zhihui,Yuan, Mingbin
, p. 7225 - 7234 (2020)
The merger of photoredox and nickel catalysis has enabled the construction of quaternary centers. However, the mechanism, role of the ligand, and effect of the spin state for this transformation and related Ni-catalyzed cross-couplings involving tertiary alkyl radicals in combination with bipyridine and diketonate ligands remain unknown. Several mechanisms have been proposed, all invoking a key Ni(III) species prior to undergoing irreversible inner-sphere reductive elimination. In this work, we have used open-shell dispersion-corrected DFT calculations, quasi-classical dynamics calculations, and experiments to study in detail the mechanism of carbon-carbon bond formation in Ni bipyridine- A nd diketonate-based catalytic systems. These calculations revealed that access to high spin states (e.g., triplet spin state tetrahedral Ni(II) species) is critical for effective radical cross-coupling of tertiary alkyl radicals. Further, these calculations revealed a disparate mechanism for the C-C bond formation. Specifically, contrary to the neutral Ni-bipyridyl system, diketonate ligands lead directly to the corresponding tertiary radical cross-coupling products via an outer-sphere reductive elimination step via triplet spin state from the Ni(III) intermediates. Implications to related Ni-catalyzed radical cross-couplings and the design of new transformations are discussed.
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Brown
, p. 3232,3233 (1959)
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Spagnolo et al.
, p. 2006 (1971)
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Enabling Metallophotoredox Catalysis in Parallel Solution-Phase Synthesis Using Disintegrating Reagent Tablets
Borlinghaus, Niginia,Sch?nfeld, Barbara,Heitz, Stephanie,Klee, Johanna,Vukeli?, Stella,Braje, Wilfried M.,Jolit, Anais
, p. 16535 - 16547 (2021/12/02)
Compressed tablets containing a mixture of a photocatalyst, a nickel catalyst, an inorganic base, and an inert excipient are employed as a fast, safe, and user-friendly chemical delivery system for two different metallophotoredox-catalyzed reactions. This delivery method simplifies the preparation of compound libraries using photoredox chemistry in a parallel setting. The reagent tablets were successfully applied to late-stage functionalization of drug-like intermediates. These tablets can be prepared with various reagents and catalysts in different sizes and be stored on the bench thanks to blister packaging.
Highly Efficient Oxidative Cyanation of Aldehydes to Nitriles over Se,S,N-tri-Doped Hierarchically Porous Carbon Nanosheets
Hua, Manli,Song, Jinliang,Huang, Xin,Liu, Huizhen,Fan, Honglei,Wang, Weitao,He, Zhenhong,Liu, Zhaotie,Han, Buxing
supporting information, p. 21479 - 21485 (2021/08/23)
Oxidative cyanation of aldehydes provides a promising strategy for the cyanide-free synthesis of organic nitriles. Design of robust and cost-effective catalysts is the key for this route. Herein, we designed a series of Se,S,N-tri-doped carbon nanosheets with a hierarchical porous structure (denoted as Se,S,N-CNs-x, x represents the pyrolysis temperature). It was found that the obtained Se,S,N-CNs-1000 was very selective and efficient for oxidative cyanation of various aldehydes including those containing other oxidizable groups into the corresponding nitriles using ammonia as the nitrogen resource below 100 °C. Detailed investigations revealed that the excellent performance of Se,S,N-CNs-1000 originated mainly from the graphitic-N species with lower electron density and synergistic effect between the Se, S, N, and C in the catalyst. Besides, the hierarchically porous structure could also promote the reaction. Notably, the unique feature of this metal-free catalyst is that it tolerated other oxidizable groups, and showed no activity on further reaction of the products, thereby resulting in high selectivity. As far as we know, this is the first work for the synthesis of nitriles via oxidative cyanation of aldehydes over heterogeneous metal-free catalysts.
One pot synthesis of aryl nitriles from aromatic aldehydes in a water environment
Chen, Qingqing,Han, Hongwei,Lin, Hongyan,Ma, Xiaopeng,Qi, Jinliang,Wang, Xiaoming,Yang, Yonghua,Zhou, Ziling
, p. 24232 - 24237 (2021/07/29)
In this study, we found a green method to obtain aryl nitriles from aromatic aldehyde in water. This simple process was modified from a conventional method. Compared with those approaches, we used water as the solvent instead of harmful chemical reagents. In this one-pot conversion, we got twenty-five aryl nitriles conveniently with pollution to the environment being minimized. Furthermore, we confirmed the reaction mechanism by capturing the intermediates, aldoximes.
