645-58-9Relevant articles and documents
Phosphine-Free Manganese Catalyst Enables Selective Transfer Hydrogenation of Nitriles to Primary and Secondary Amines Using Ammonia-Borane
Sarkar, Koushik,Das, Kuhali,Kundu, Abhishek,Adhikari, Debashis,Maji, Biplab
, p. 2786 - 2794 (2021/03/03)
Herein we report the synthesis of primary and secondary amines by nitrile hydrogenation, employing a borrowing hydrogenation strategy. A class of phosphine-free manganese(I) complexes bearing sulfur side arms catalyzed the reaction under mild reaction conditions, where ammonia-borane is used as the source of hydrogen. The synthetic protocol is chemodivergent, as the final product is either primary or secondary amine, which can be controlled by changing the catalyst structure and the polarity of the reaction medium. The significant advantage of this method is that the protocol operates without externally added base or other additives as well as obviates the use of high-pressure dihydrogen gas required for other nitrile hydrogenation reactions. Utilizing this method, a wide variety of primary and symmetric and asymmetric secondary amines were synthesized in high yields. A mechanistic study involving kinetic experiments and high-level DFT computations revealed that both outer-sphere dehydrogenation and inner-sphere hydrogenation were predominantly operative in the catalytic cycle.
Synthesis of cobalt nanoparticles by pyrolysis of Vitamin B12: A non-noble-metal catalyst for efficient hydrogenation of nitriles
Ferraccioli, Raffaella,Borovika, Diana,Surkus, Annette-Enrica,Kreyenschulte, Carsten,Topf, Christoph,Beller, Matthias
, p. 499 - 507 (2018/02/07)
A facile preparation of vitamin B12-derived carbonaceous cobalt particles supported on ceria is reported. The resulting composite material is obtained upon wet impregnation of ceria with natural cyanocobalamin and consecutive pyrolysis under inert conditions. The novel catalyst shows good to excellent performance in the industrially relevant heterogeneous hydrogenation of nitriles to the corresponding primary amines.
Selective Catalytic Hydrogenations of Nitriles, Ketones, and Aldehydes by Well-Defined Manganese Pincer Complexes
Elangovan, Saravanakumar,Topf, Christoph,Fischer, Steffen,Jiao, Haijun,Spannenberg, Anke,Baumann, Wolfgang,Ludwig, Ralf,Junge, Kathrin,Beller, Matthias
supporting information, p. 8809 - 8814 (2016/07/29)
Hydrogenations constitute fundamental processes in organic chemistry and allow for atom-efficient and clean functional group transformations. In fact, the selective reduction of nitriles, ketones, and aldehydes with molecular hydrogen permits access to a green synthesis of valuable amines and alcohols. Despite more than a century of developments in homogeneous and heterogeneous catalysis, efforts toward the creation of new useful and broadly applicable catalyst systems are ongoing. Recently, Earth-abundant metals have attracted significant interest in this area. In the present study, we describe for the first time specific molecular-defined manganese complexes that allow for the hydrogenation of various polar functional groups. Under optimal conditions, we achieve good functional group tolerance, and industrially important substrates, e.g., for the flavor and fragrance industry, are selectively reduced.
