622-80-0Relevant articles and documents
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Corson,Dressler
, p. 474 (1956)
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BF3·Et2O as a metal-free catalyst for direct reductive amination of aldehydes with amines using formic acid as a reductant
Fan, Qing-Hua,Liu, Xintong,Luo, Zhenli,Pan, Yixiao,Xu, Lijin,Yang, Ji,Yao, Zhen,Zhang, Xin
supporting information, p. 5205 - 5211 (2021/07/29)
A versatile metal- and base-free direct reductive amination of aldehydes with amines using formic acid as a reductant under the catalysis of inexpensive BF3·Et2O has been developed. A wide range of primary and secondary amines and diversely substituted aldehydes are compatible with this transformation, allowing facile access to various secondary and tertiary amines in high yields with wide functional group tolerance. Moreover, the method is convenient for the late-stage functionalization of bioactive compounds and preparation of commercialized drug molecules and biologically relevant N-heterocycles. The procedure has the advantages of simple operation and workup and easy scale-up, and does not require dry conditions, an inert atmosphere or a water scavenger. Mechanistic studies reveal the involvement of imine activation by BF3and hydride transfer from formic acid.
Catalyst-free photoinduced selective oxidative C(sp3)-C(sp3) bond cleavage in arylamines
Duan, Wentao,Lian, Qi,Wang, Songping,Wei, Wentao,Zhou, Jingwei
supporting information, p. 3261 - 3267 (2021/05/21)
Due to the directional nature of sp3-hybridized orbitals and the absence of π-orbitals, the oxidative cleavage of the kinetically and thermodynamically stable C(sp3)-C(sp3) bond is extremely difficult and remains scarcely explored. In this work, under the double argument of quantum mechanics (QM) computations and meticulous experiments on our well-designed C-C single bond cleavage mechanism, we discovered a means of photoinduced selective oxidative C(sp3)-C(sp3) bond cleavage in arylamines, easily achieved by simple visible light irradiation using O2as a benign oxidant under very mild conditions. The utility of our methodology was demonstrated by the C(sp3)-C(sp3) bond cleavage in morpholine/piperazine arylamines with excellent functional group tolerance. Importantly, our methodology is noteworthy, not only in that it does not require any catalysts, but also in that it provides valuable possibilities for the scalable functionalization of clinical drugs and natural products.
Development of Carbon-Neutral Cellulose-Supported Heterogeneous Palladium Catalysts for Chemoselective Hydrogenation
Yamada, Tsuyoshi,Teranishi, Wataru,Park, Kwihwan,Jiang, Jing,Tachikawa, Takumu,Furusato, Shinichi,Sajiki, Hironao
, p. 4052 - 4058 (2020/07/13)
Palladium catalysts immobilized on cellulose particles (Pd/CLP) and on a cellulose-monolith (Pd/CLM) were developed. These composites were applied as hydrogenation catalysts and their catalyst activities were evaluated. Although both catalysts catalyzed the deprotection of benzyloxycarbonyl-protected aromatic amines (Ar-N-Cbz) and aromatic benzyl esters (Ar-CO2Bn), only Pd/CLM could accomplish the hydrogenolysis of aliphatic-N-Cbz and aliphatic-CO2Bn protective groups. The difference in the physical structure of the cellulose supports induced unique chemoselectivity. Aliphatic-N-Cbz and aliphatic-CO2Bn groups were tolerated under the Pd/CLP-catalyzed hydrogenation conditions, while Ar-N-Cbz, Ar-CO2Bn, alkene, alkyne, azido and nitro groups could be smoothly reduced.