823188-83-6Relevant articles and documents
Switching Selectivity in Copper-Catalyzed Transfer Hydrogenation of Nitriles to Primary Amine-Boranes and Secondary Amines under Mild Conditions
Song, Hao,Xiao, Yao,Zhang, Zhuohua,Xiong, Wanjin,Wang, Ren,Guo, Liangcheng,Zhou, Taigang
, p. 790 - 800 (2022/01/11)
A simple and efficient copper-catalyzed selective transfer hydrogenation of nitriles to primary amine-boranes and secondary amines with an oxazaborolidine-BH3 complex is reported. The selectivity control was achieved under mild conditions by switching the solvent and the copper catalysts. More than 30 primary amine-boranes and 40 secondary amines were synthesized via this strategy in high selectivity and yields of up to 95%. The strategy was applied to the synthesis of 15N labeled in 89% yield.
Platinum Nanoparticles Uniformly Dispersed on Covalent Organic Framework Supports for Selective Synthesis of Secondary Amines
Li, Xinjun,Liu, Jianguo,Ma, Longlong,Tang, Long,Wang, Chenguang,Wang, Nan
, (2022/01/22)
Covalent organic frameworks (COFs) with pore structures are talented supports for active components. In this report, COF has been rationally fabricated and served as host for growing uniformly dispersed platinum nanoparticles with a narrow size distribution (2 nm). The obtained hybrid Pt/COF exhibits high catalytic activity in the reductive amination of benzaldehyde towards secondary amines with a yield of 96 % and good recyclability. The preferable selectivity towards secondary amines could be attributed to synergistic effects of active platinum nanoparticles and COF, in which metallic Pt nanoparticles were uniformly dispersed with a positively charged surface. This work will open an avenue towards controlling the interaction between active metals and support as well as rational design of catalysts for demanding transformations for fine agrochemicals intermediates.
Surface modification boosts exciton extraction in confined layered structure for selective oxidation reaction
Jin, Sen,Wang, Hui,Li, Lei,Luo, Xiao,Sun, Xianshun,Zuo, Ming,Tian, Jie,Zhang, Xiaodong,Xie, Yi
, p. 1964 - 1969 (2021/10/25)
Extracting photogenerated species from bulk to surface is an essential process for gaining efficient semiconductor-based photocatalysis. However, compared with charged photogenerated carriers, neutral exciton exhibits negligible response to electric field. Accordingly, traditional strategies involving band-alignment construction for boosting directional transfer of charge carriers are impracticable for extracting bulk excitons. To this issue, we here propose that the extraction of bulk exciton could be effectively implemented by surface modification. By taking confined layered bismuth oxycarbonate (Bi2O2CO3) as an example, we highlight that the incorporation of iodine atoms on the surface could modify the micro-region electronic structure and hence lead to reduced energy of surface excitonic states. Benefiting from the energy gradient between bulk and surface excitonic states, iodine-modified Bi2O2CO3 possesses high-efficiency bulk exciton extraction, and hence exhibits promoted performance in triggering 1O2-mediated selective oxidation reaction. This work presents the positive role of surface modification in regulating excitonic processes of semiconductor-based photocatalysts. [Figure not available: see fulltext.].
Selective Synthesis of Secondary Amines from Nitriles by a User-Friendly Cobalt Catalyst
Sharma, Dipesh M.,Punji, Benudhar
supporting information, p. 3930 - 3936 (2019/07/12)
Selective hydrogenation/reductive amination of nitriles to secondary amines catalyzed by an inexpensive and user-friendly cobalt complex, (Xantphos)CoCl2, is reported. The use of (Xantphos)CoCl2 and ammonia borane (NH3?BH3) combination affords the selective reduction of nitriles to symmetrical secondary amines, whereas the employment of (Xantphos)CoCl2 and dimethylamine borane (Me2NH?BH3) along with external amines produce unsymmetrical secondary amines and tertiary amines. The general applicability of this methodology is demonstrated by the synthesis of 43 symmetrical and unsymmetrical secondary and tertiary amines bearing diverse functionalities. (Figure presented.).
Cationic Iridium and Rhodium Complexes with C-N Chelating Primary Benzylic Amine Ligands as Potent Catalysts for Hydrogenation of Unsaturated Carbon-Nitrogen Bonds
Sato, Yasuhiro,Kayaki, Yoshihito,Ikariya, Takao
, p. 1257 - 1264 (2016/06/01)
Cationic half-sandwich C-N chelating Ir and Rh complexes [Cp?M(NCCH3){2(N,C)-NH2CR2-2-C6H4}]+SbF6- (1a, M = Ir, R = CH3; 1b, M = Ir, R = C6H5; 2a, M = Rh, R = CH3; 2b, M = Rh, R = C6H5) are synthesized by AgSbF6-mediated halide abstraction from neutral azametallacycles derived from tritylamine or cumylamine and are fully characterized by NMR spectroscopy and X-ray crystallography. The treatment of the cationic complex 1b with H2 gas under ambient conditions in the presence of triethylamine in THF-d8 quantitatively yielded hydrido(amine) complex [Cp?Ir(H){2(N,C)-NH2C(C6H5)2-2-C6H4}] (4). The C-N chelating Ir complex shows a higher catalytic activity than an N-N chelating complex, [Cp?Ir(NCCH3)(Tscydn)]+SbF6- (3; Tscydn = N-(p-toluenesulfonyl)-1,2-cyclohexanediamime), that has been previously used for the asymmetric hydrogenation of acyclic imines. For example, the cationic Ir complex 1a promoted the hydrogenation of N-(1-phenylethylidene)benzylamine under 30 atm at 30 °C in the presence of excess AgSbF6 to produce the corresponding amine in 97% yield within 2 h. The cationic Rh complexes 2 serve as efficient catalysts for hydrogenative condensation of nitriles in the presence of AgSbF6, producing dibenzylamines selectively even at 60 °C.
TACHYKININ RECEPTOR ANTAGONISTS
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Page 29, (2010/02/10)
The present invention relates to selective NK-1 receptor antagonists of Formula (I) or a pharmaceutically acceptable salt thereof, for the treatment of disorders associated with an excess of tachykinins.
Turning the product selectivity of nitrile hydrogenation from primary to secondary amines by precise modification of Pd/SiC catalysts using NiO nanodots
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, (2019/05/21)
The selectivity of supported metal catalysts is mainly determined by the active metallic component, and thus turning the selectivity to a completely different product is rarely achieved by modification of the catalysts. Hydrogenation of nitriles is an efficient and environmentally benign route for the synthesis of valuable amines, but it usually produces mixtures of primary, secondary and even tertiary amines. Herein we report that the selectivity of Pd/SiC catalysts for the hydrogenation of nitriles with H2 can be turned from primary to secondary amines by modification of NiO nanodots. In the modified catalysts, the NiO nanodots act as reactive sites to consume hydrogen radicals on the Pd surface, and thus prolong the lifetime of an imine intermediate that determines the product selectivity. Under mild conditions (30 °C, atmospheric H2), Pd/SiC and NiO-Pd/SiC catalysts exhibit high selectivity to primary (94%) and secondary (99%) amines, respectively.
