2362-79-0Relevant articles and documents
Experimental and theoretical investigation of benzyl-N-pyrrolylketene, one- step procedure for preparing of new β-lactams by [2 +2] cycloaddition reaction
Behzadi, Masoumeh,Saidi, Kazem,Islami, Mohammad Reza,Khabazzadeh, Hojatollah
, p. 111 - 117 (2016)
3-Phenyl-2-(1-H-pyrrol-1-yl) propanoic acid has been used as a ketene source in synthesizing of monocyclic-2-azetidinones. Hindrance in ketene and imines successfully controlled the diastereoselectivity of the reaction. For example, in some cases only one isomer was achieved. By using Mukaiyama reagent, the leaving group in acid was activated and the by-products were separated by simple aqueous work-up. DFT calculation indicated that the benzyl-N-pyrrolylketene has nonconjugated structure and the pyrrolyl ring is perpendicular to the ketene plane in both the twisted and planar structures.
Stereoselective synthesis of new β-lactams from the main functional group of indomethacin
Amiri, Mojgan,Islami, Mohammad Reza,Mortazavi, Zahra Fahimeh al-Sadat
, (2022/01/31)
New β-lactams were synthesized in moderate yields from indomethacin, which is currently used as a drug to relieve pain such as arthritis, muscle and bone damage. The reaction was carried out by [2 + 2] cycloaddition of the in situ formed indomethacinyl ke
Cobalt-Catalyzed Deoxygenative Hydroboration of Nitro Compounds and Applications to One-Pot Synthesis of Aldimines and Amides
Gudun, Kristina A.,Zakarina, Raikhan,Segizbayev, Medet,Hayrapetyan, Davit,Slamova, Ainur,Khalimon, Andrey Y.
, p. 601 - 611 (2021/11/30)
The commercially available and bench-stable Co(acac)2 ligated with bis[(2-diphenylphosphino)phenyl] ether (dpephos) was employed for selective room temperature hydroboration of nitro compounds with HBPin (TOF up to 4615 h?1), tolerating halide, hydroxy, amino, ether, ester, lactone, amide and heteroaromatic functionalities. These reactions offered a direct access to a variety of N-borylamines RN(H)BPin, which were in situ treated with aldehydes and carboxylic acids to produce a series of aldimines and secondary carboxamides without the need for dehydrating and/or coupling reagents. Combination of these transformations in a sequential one-pot manner allowed for direct and selective synthesis of aldimines and secondary carboxamides from readily available and inexpensive nitro compounds.
Nanomagnetic catalysis (Fe3O4@S–TiO2): a novel magnetically nano catalyst for the synthesis of new highly substituted tetrahydropyridine derivatives under solvent-free conditions
Nezami, Zahra,Eshghi, Hossein
, p. 1997 - 2008 (2021/01/20)
A novel nanomagnetic catalyst (Fe3O4@S–TiO2) was prepared by the hydrothermal method. At the first, Fe3O4 nanoparticles were synthesized, then iron oxide nanoparticles (IONPs) were dispersed in ethano
Visible-Light-Induced Cycloaddition of α-Ketoacylsilanes with Imines: Facile Access to β-Lactams
Ye, Jian-Heng,Bellotti, Peter,Paulisch, Tiffany O.,Daniliuc, Constantin G.,Glorius, Frank
supporting information, p. 13671 - 13676 (2021/05/11)
We report the synthesis of β-lactams from α-ketoacylsilanes and imines, which proceeds via a formal [2+2] photochemical cycloaddition with in situ generation of siloxyketene. This mild and operationally simple reaction proceeds in an atom-economic fashion with broad substrate scope, including aldimines, ketimines, hydrazones, and fused nitrogen heterocycles, affording a variety of important β-lactams with satisfactory diastereoselectivities in most cases. This reaction also features good functional-group tolerance, facile scalability and product diversification. Experimental and computational studies suggest that α-ketoacylsilanes can serve as photochemical precursors by engaging in a 1,3 silicon shift to the distal carbonyl group.
Sulfated polyborate: A dual catalyst for the reductive amination of aldehydes and ketones by NaBH4
Ganwir, Prerna,Chaturbhuj, Ganesh
supporting information, (2021/05/19)
An efficient, quick, and environment-friendly one-pot reductive amination of aldehydes or ketones was developed. In ethanol at 70 °C, a imination catalyzed by sulfated polyborate and further reduced by sodium borohydride yields various amines. The present method has many significant benefits, including a shorter reaction time, excellent yields, and a hassle-free, straightforward experimental process. The reaction has a wide range of applications due to its flexibility, including secondary amine for reductive amination.
Aza-peterson olefinations: Rapid synthesis of (E)-alkenes
Britten, Thomas K.,Basson, Ashley J.,Roberts, Dean D.,McLaughlin, Mark G.
, p. 3535 - 3544 (2021/06/03)
An aza-Peterson olefination methodology to access 1,3-dienes and stilbene derivatives from the corresponding allyl- or benzyltrimethylsilane is described. Silanes can be deprotonated using Schlosser's base and added to N -phenyl imines or ketones to directly give the desired products in high yields.
Rhodium catalyzed multicomponent dehydrogenative annulation: one-step construction of isoindole derivatives
Cheng, Biao,Lyu, Hairong,Quan, Yangjian,Xie, Zuowei
supporting information, p. 7930 - 7933 (2021/08/17)
A strategy for one-pot synthesis of isoindoles is describedviaa catalytic multicomponent dehydrogenative annulation of diarylimines, vinyl ketones and simple amines. In the presence of a rhodium catalyst and Cu oxidant, four C-H and two N-H bonds are activated along with the formation of one new C-C and two new C-N bonds, leading to a series of isoindole derivatives in good to very high isolated yields.
Direct synthesis of imines from nitro compounds and biomass-derived carbonyl compounds over nitrogen-doped carbon material supported Ni nanoparticles
Li, Bo,Wang, Yanxin,Chi, Quan,Yuan, Ziliang,Liu, Bing,Zhang, Zehui
, p. 4464 - 4471 (2021/03/15)
The selective synthesis of imines from biomass-derived chemicals over heterogeneous non-noble metal catalysts is of great importance for organic transformation. Herein, non-noble heterogeneous nitrogen-doped carbon supported Ni catalysts (abbreviated as Ni/CN-MgO-T, whereTrepresents the pyrolysis temperature) have been facilely prepared from the simple pyrolysis of Ni precursors and biomass, and Ni/CN-MgO-600 with the smallest size of Ni nanoparticles demonstrated the highest catalytic activity. The reductive coupling of nitroarenes and carbonyl compounds could be performed under mild conditions (80 °C, and 10 bar H2), affording structurally-diverse imines with high to excellent yields (84.2-98.1%). Thanks to the mild reaction conditions, the developed method showed good tolerance to other functional groups such as nitriles, halogen and vinyl groups.
Highly chemoselective synthesis of imine over Co/Zn bimetallic MOFs derived Co3ZnC-ZnO embed in carbon nanosheet catalyst
Li, Guangming,Li, Jingfang,Li, Weizuo,Li, Xuewei,Mao, Guijie,She, Wei,Wang, Jing
, p. 17 - 26 (2021/07/28)
One-pot direct synthesis of imines via reductive amination of nitroarenes with aromatic aldehydes remains a great challenge due in part to its over-hydrogenation of imines to secondary amines. Herein, a novel Co3ZnC and ZnO supported on N-doped carbon nanosheet catalyst with the thickness of ca. 5.0 nm was fabricated through the direct pyrolysis of a Co/Zn bimetallic MOFs at 500 °C (named as Co3ZnC-ZnO/NC-500). Surprisingly, the developed Co3ZnC-ZnO/NC-500 catalyst delivers 99.9 % conversion of nitrobenzene and 98.5 % selectivity to N-benzylideneaniline in one-pot reductive amination of nitrobenzene with benzaldehyde. Various characterizations (including as SEM, XRD, TEM, AFM, XPS, Raman and N2 adsorption–desorption) have revealed that the generated small size of Co3ZnC alloy, abundant structural defects, larger specific surface area (105.5 m2·g?1) as well as more basic sites are responsible for the outstanding catalytic activity of Co3ZnC-ZnO/NC-500 catalyst for tandem reaction. Moreover, the Co3ZnC-ZnO/NC-500 catalyst exhibits high stability during the recycling experiments without the loss of its catalytic activity. Notably, the results of contrast experiments have demonstrated that the intentional introduction of ZnO in Co3ZnC-ZnO/NC-500 catalyst plays a key role in the selectivity to N-benzylideneaniline in the tandem reaction. This study provides a new guideline for designing tandem catalysts with high selectivity.
