36178-60-6Relevant academic research and scientific papers
N -Alkylation of organonitrogen compounds catalyzed by methylene-linked bis-NHC half-sandwich ruthenium complexes
Botubol-Ares, José Manuel,Collado, Isidro G.,Jiménez-Tenorio, Manuel,Moutaoukil, Zakaria,Serrano-Díez, Emmanuel
supporting information, p. 831 - 839 (2022/02/03)
An efficient ruthenium-catalyzed N-alkylation of amines, amides and sulfonamides has been developed employing novel pentamethylcyclopentadienylruthenium(ii) complexes bearing the methylene linked bis(NHC) ligand bis(3-methylimidazol-2-ylidene)methane. The
Continuous flow heterogeneous catalytic reductive aminations under aqueous micellar conditions enabled by an oscillatory plug flow reactor
?tv?s, Sándor B.,Buchholcz, Balázs,Darvas, Ferenc,Kappe, C. Oliver,Novák, Zoltán,Sipos, Gellért,Wernik, Michaela
supporting information, p. 5625 - 5632 (2021/08/16)
Despite the fact that continuous flow processing exhibits well-established technical advances, aqueous micellar chemistry, a field that has proven extremely useful in shifting organic synthesis to sustainable water-based media, has mostly been explored under conventional batch-based conditions. This is particularly because of the fact that the reliable handling of slurries and suspensions in flow has been considered as a significant technical challenge. Herein, we demonstrate that the strategic application of an oscillatory plug flow reactor enables heterogeneous catalytic reductive aminations in aqueous micellar media enhancing mass transport and facilitating process simplicity, stability and scalability. The micellar flow process enabled a broad range of substrates, including amino acid derivatives, to be successfully transformed under reasonably mild conditions utilizing only very low amounts of Pd/C as a readily available heterogeneous catalyst. The preparative capabilities of the process along with the recyclability of the heterogenous catalyst and the aqueous reaction media were also demonstrated. This journal is
DIACYLGLYCEROL KINASE MODULATING COMPOUNDS
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Paragraph 1156, (2021/07/02)
The present disclosure provides diacylglycerol kinase modulating compounds, and pharmaceutical compositions thereof, for treating cancer, including solid tumors, and viral infections, such as HIV or hepatitis B virus infection. The compounds can be used alone or in combination with other agents.
Cross dehydrogenative coupling strategy for allylation of benzylanilines promoted by DDQ
Xiong, Ruimei,Hussain, Muhammad Ijaz,Liu, Qing,Xia, Wen,Xiong, Yan
, (2019/12/11)
A cross dehydrogenative coupling strategy for allylation of benzylanilines promoted by DDQ is reported, which uses nonmetallic quinone DDQ as an oxidant in the allylation of N-benzylanilines under mild conditions. C–C bond with high selectivity and activity was constructed in this reaction and homoallylic amines were obtained with yields of up to 99%.
Mechanistic Studies of Hydride Transfer to Imines from a Highly Active and Chemoselective Manganate Catalyst
Freitag, Frederik,Irrgang, Torsten,Kempe, Rhett
supporting information, p. 11677 - 11685 (2019/08/20)
We introduce a highly active and chemoselective manganese catalyst for the hydrogenation of imines. The catalyst has a large scope, can reduce aldimines and ketimines, and tolerates a variety of functional groups, among them hydrogenation sensitive examples such as an olefin, a ketone, nitriles, nitro groups, and an aryl iodo substituent or a benzyl ether. We could investigate the transfer step between imines and the hydride complex in detail. We found that double deprotonation of the ligand is essential and excess base does not lead to a higher rate in the transfer step. We identified the actual hydrogenation catalyst as a K-Mn-bimetallic species and could obtain a structure of the K-Mn complex formed after hydride transfer by X-ray analysis. NMR experiments indicate that the hydride transfer is a well-defined reaction, which is first order in imine, first order in the bimetallic (K-Mn) hydride, and independent in rate from the concentration of the potassium base. We propose an outer-sphere mechanism in which protons do not seem to be involved in the rate-determining step, leading to a transiently negatively charged nitrogen atom in the substrate which reacts rapidly with HOtBu (2-methylpropan-2-ol) to produce the amine. This is based on several observations, such as no dependency of the reaction rate on the HOtBu concentration, no observable manganese amide complex, and a high reaction constant in a conducted Hammett study. Furthermore, hydrogen transfer of the catalytic cycle was experimentally probed and monitored by NMR with subsequent quantitative regeneration of the catalyst by H2.
Cross-dehydrogenative coupling strategy for phosphonation and cyanation of secondary N-alkyl anilines by employing 2,3-dichloro-5,6-dicyanobenzoquinone
Liu, Qing,Yu, Shuchen,Hu, Liangzhen,Hussain, Muhamad Ijaz,Zhang, Xiaohui,Xiong, Yan
, p. 7209 - 7217 (2018/11/10)
The cross-dehydrogenative coupling strategy for metal-free phosphonation and cyanation of secondary N-alkyl anilines has been developed firstly under mild reaction conditions. Based on detailed optimization of reaction conditions, the substrate generality of N-alkyl anilines and various hydrogen phosphonates has been investigated, and a series of versatile α-aminophosphonates and α-aminonitriles were therefore furnished in good to excellent yields. A plausible collective reaction mechanism through dehydrogenation to imine formation, then to respective α-aminophosphonates and α-aminonitriles was proposed.
Highly Efficient Rh(I) Homo- and Heterogeneous Catalysts for C-N Couplings via Hydrogen Borrowing
Wong, Chin M.,Peterson, Matthew B.,Pernik, Indrek,McBurney, Roy T.,Messerle, Barbara A.
supporting information, p. 14682 - 14687 (2017/12/15)
Rhodium(I) complexes were explored as catalysts for the hydrogen borrowing reactions of amines and alcohols. Bidentate carbene-triazole ligands were readily synthesized via "click" reactions which allowed a diversity of ligand backbones to be accessed. The catalytic transformations are highly efficient, able to reach completion in under 6 h, and promote C-N bond formation across a range of primary alcohol and amine substrates. Moreover, site-selective catalysis can be achieved using substrates with more than one reactive site. A rhodium(I) complex covalently attached to a carbon black surface was also deployed in the hydrogen borrowing coupling reaction of aniline with benzyl alcohol. This represents the first report of a heterogeneous rhodium catalyst used for hydrogen borrowing.
Iridium(iii) homo- and heterogeneous catalysed hydrogen borrowing C-N bond formation
Wong, Chin M.,McBurney, Roy T.,Binding, Samantha C.,Peterson, Matthew B.,Gon?ales, Vinicius R.,Gooding, J. Justin,Messerle, Barbara A.
supporting information, p. 3142 - 3151 (2017/07/24)
Pentamethylcyclopentadienyl iridium(iii) complexes of bidentate carbene-triazole ligands were found to be excellent homogeneous catalysts for the hydrogen borrowing mediated coupling of alcohols with amines. The reactions are highly efficient, able to reach completion in under 6 h at 100 °C at low catalyst loadings of 0.5 mol%, and are environmentally benign, the only by-product is water. The Ir(iii) catalysts promoted C-N bond formation across a range of alcohol and amine substrates, including biologically relevant motifs. Covalent attachment to a carbon black surface generated a well-defined "hybrid" heterogeneous catalyst which gave good conversion to products in the coupling reaction of aniline with benzyl alcohol, and could be recycled with no catalyst leeching. This represents the first report of a covalently linked heterogeneous iridium catalyst on carbon used for hydrogen borrowing. Turnover numbers (TON) for the heterogeneous were found to be significantly higher than the corresponding homogeneous reaction. To elucidate the homogeneous reaction mechanism, 1H NMR studies inconjuction with deuteration experiments allowed a mechanism to be postulated.
Formation of Phenyliodonio-Substituted Spirofurooxindole Trifluoroacetates from N-Substituted 3-Oxopentanediamides via Phenyliodine Bis(trifluoroacetate)-Mediated Oxidative Cascade Reactions
Hu, Bei,Cao, Yang,Zhang, Bobo,Zhang-Negrerie, Daisy,Du, Yunfei
supporting information, p. 2542 - 2548 (2017/08/16)
The reaction of N-substituted 3-oxopentanediamides with phenyliodine bis(trifluoroacetate) (PIFA) was found to give a novel class of phenyliodonio-substituted spirofurooxindole trifluoroacetates under metal-free conditions. The reaction is postulated to proceed via a cascade process involving an oxidative C—O bond formation, an oxidative C—C bond formation and a final iodination step. (Figure presented.).
Benzimidazolin-2-ylidene N-heterocyclic carbene complexes of ruthenium as a simple catalyst for the N-alkylation of amines using alcohols and diols
Shan, Siah Pei,Xiaoke, Xie,Gnanaprakasam, Boopathy,Dang, Tuan Thanh,Ramalingam, Balamurugan,Huynh, Han Vinh,Seayad, Abdul Majeed
, p. 4434 - 4442 (2015/02/19)
Simple air and moisture stable ruthenium complexes 1-3 and 3a were synthesized from readily available benzannulated N-heterocyclic carbene ligands (bimy = benzimidazolin-2-ylidene). These complexes were found to be efficient catalysts for the alkylation of amines using alcohols as alkylating agents. Catalysts 1, 2 and 3a gave excellent yields of up to 99% for the alkylation of various amines using benzylic and aliphatic alcohols at 130 °C for 18 h under solventless conditions. Catalyst 3a bearing both phosphine and carbene ligands gave excellent yields of up to 98% for the synthesis of heterocyclic amines by double alkylation of primary amines using linear diols. The practical utility of these catalysts was demonstrated for the synthesis of pharmaceutically important amines in a more environmentally benign way under solventless conditions.
