56866-32-1Relevant academic research and scientific papers
Ammonium Chloride-Promoted Rapid Synthesis of Monosubstituted Ureas under Microwave Irradiation
Lan, Chunling Blue,Auclair, Karine
supporting information, p. 5135 - 5146 (2021/10/19)
Monosubstituted ureas are important scaffolds in organic chemistry. They appear in various biologically active compounds and serve as versatile precursors in synthesis. Monosubstituted ureas were originally prepared using toxic and hazardous phosgene equivalents. Modern methods include transamidation of urea and nucleophilic addition to cyanate salts, both of which suffer from a narrow substrate scope due to the need for a strong acid and prolonged reaction times. We hereby report that ammonium chloride can promote the reaction between amines and potassium cyanate to generate monosubstituted ureas in water. This method proceeds rapidly under microwave irradiation and tolerates a broad range of functional groups. Unlike previous strategies, it is compatible with other nucleophiles, acid-labile moieties, and most of the common protecting groups. The products precipitate out of solution, allowing facile isolation without column chromatography.
Conjugated molecule based 2D perovskites for high-performance perovskite solar cells
Chen, Hanlin,Chen, Rui,Gong, Xiong,Shen, Lening,Wang, Junpeng,Yang, Yongrui,Zheng, Jie,Zheng, Luyao,Zhu, Tao
supporting information, p. 21910 - 21917 (2021/10/12)
Conjugated molecules have been typically utilized as either hole or electron extraction layers to boost the device performance of perovskite solar cells (PSCs), formed from three-dimensional (3D) perovskites, due to their high charge carrier mobility and electrical conductivity. However, the passivating role of conjugated molecules in creating two-dimensional (2D) perovskites has rarely been reported. In this study, we report novel conjugated aniline 3-phenyl-2-propen-1-amine (PPA) based 2D perovskites and further demonstrate efficient and stable PSCs containing a (PPA)x(MAPbI3)1?x/MAPbI3bilayer thin film (where MA is CH3NH3+). The (PPA)x(MAPbI3)1?x/MAPbI3bilayer thin film possesses superior crystallinity and passivated trap states, resulting in enhanced charge transport and suppressed charge carrier recombination compared to those of a 3D MAPbI3thin film. As a result, PSCs containing the (PPA)x(MAPbI3)1?x/MAPbI3bilayer thin film exhibit a power conversion efficiency (PCE) of 21.98%, which is approximately a 25% enhancement compared to that of the MAPbI3thin film. Moreover, un-encapsulated PSCs containing the (PPA)x(MAPbI3)1?x/MAPbI3bilayer thin film retain 50% of their initial PCE after 1200 hours in an ambient atmosphere (25 °C, and 30 ± 10 humidity), whereas PSCs with the 3D MAPbI3thin film show significant degradation after 100 hours and a degradation of more than 50% of their original PCE after 500 hours. These results demonstrate that the incorporation of conjugated molecules as organic spacer cations to create 2D perovskites on top of 3D perovskites is an effective way to approach high-performance PSCs.
Regioselective intramolecular Markovnikov and anti-Markovnikov hydrofunctionalization of alkenes: Via photoredox catalysis
Li, Na,Man, Yunquan,Tang, Bo,Wang, Hongyu,Wang, Kaiye,Xiang, Yanan
supporting information, p. 11426 - 11429 (2019/09/30)
Highly regioselective Markovnikov hydrofunctionalization of alkenes was successfully realized via photoredox catalysis by introducing a urea group and fine tuning the hydrogen atom transfer catalysts. The anti-Markovnikov hydroamination of alkenes was also achieved with high yields and stereoselectivities in this work.
Palladium-catalysed anti-Markovnikov selective oxidative amination
Kohler, Daniel G.,Gockel, Samuel N.,Kennemur, Jennifer L.,Waller, Peter J.,Hull, Kami L.
, p. 333 - 340 (2018/02/27)
In recent years, the synthesis of amines and other nitrogen-containing motifs has been a major area of research in organic chemistry because they are widely represented in biologically active molecules. Current strategies rely on a multistep approach and require one reactant to be activated prior to the carbon-nitrogen bond formation. This leads to a reaction inefficiency and functional group intolerance. As such, a general approach to the synthesis of nitrogen-containing compounds from readily available and benign starting materials is highly desirable. Here we present a palladium-catalysed oxidative amination reaction in which the addition of the nitrogen occurs at the less-substituted carbon of a double bond, in what is known as anti-Markovnikov selectivity. Alkenes are shown to react with imides in the presence of a palladate catalyst to generate the terminal imide through trans-aminopalladation. Subsequently, olefin isomerization occurs to afford the thermodynamically favoured products. Both the scope of the transformation and mechanistic investigations are reported.
Tri(pentaflurophenyl)borane-catalyzed reduction of cyclic imides with hydrosilanes: Synthesis of pyrrolidines
Ding, Guangni,Wu, Xiaoyu,Lu, Bin,Lu, Wenkui,Zhang, Zhaoguo,Xie, Xiaomin
supporting information, p. 1144 - 1150 (2018/02/17)
B(C6F5)3-catalyzed hydrosilylation of cyclic imides afforded an efficient synthetic method of pyrrolidines. In the presence of 5 mol% B(C6F5)3, various aromatic, aliphatic and polycyclic imides were smoothly reduced by PhSiH3 to generate the corresponding pyrrolidines in high yields. The reaction profiles monitored by 1H NMR spectroscopy disclosed the reduction process of cyclic imides and the effect of difference structure of the hydrosilanes on the hydrosilylation.
Charge Transport between Coupling Colloidal Perovskite Quantum Dots Assisted by Functional Conjugated Ligands
Dai, Jinfei,Xi, Jun,Li, Lu,Zhao, JingFeng,Shi, Yifei,Zhang, Wenwen,Ran, Chenxin,Jiao, Bo,Hou, Xun,Duan, Xinhua,Wu, Zhaoxin
supporting information, p. 5754 - 5758 (2018/04/26)
Long alkyl-chain capping ligands are indispensable for preparing stable colloidal quantum dots. However, its insulating feature blocks efficient carrier transport among QDs, leading to inferior performance in light-emitting diodes (LEDs). The trade-off between conductivity and colloidal stability of QDs has now been overcome. Methylamine lead bromide (MAPbBr3) QDs with a conjugated alkyl-amine, 3-phenyl-2-propen-1-amine (PPA), as ligands were prepared. Owing to electron cloud overlapping and the delocalization effect of conjugated molecules, the conductivity and carrier mobility of PPA-QDs films increased almost 22 times over that of OA-QD films without compromising colloidal stability and photoluminescence. PPA-QDs LEDs exhibit a maximum current efficiency of 9.08 cd A?1, which is 8 times of that of OA-QDs LEDs (1.14 cd A?1). This work provides critical solution for the poor conductivity of QDs in applications of energy-related devices.
A Simple, Broad-Scope Nickel(0) Precatalyst System for the Direct Amination of Allyl Alcohols
Sweeney, Joseph B.,Ball, Anthony K.,Lawrence, Philippa A.,Sinclair, Mackenzie C.,Smith, Luke J.
supporting information, p. 10202 - 10206 (2018/08/06)
The preparation of allylic amines is traditionally accomplished by reactions of amines with reactive electrophiles, such as allylic halides, sulfonates, or oxyphosphonium species; such methods involve hazardous reagents, generate stoichiometric waste streams, and often suffer from side reactions (such as overalkylation). We report here the first broad-scope nickel-catalysed direct amination of allyl alcohols: An inexpensive NiII/Zn couple enables the allylation of primary, secondary, and electron-deficient amines without the need for glove-box techniques. Under mild conditions, primary and secondary aliphatic amines react smoothly with a range of allyl alcohols, giving secondary and tertiary amines efficiently. This “totally catalytic” method can also be applied to electron-deficient nitrogen nucleophiles; the practicality of the process was demonstrated in an efficient, gram-scale preparation of the calcium antagonist drug substance flunarizine (Sibelium).
Visible Light-Induced Room-Temperature Heck Reaction of Functionalized Alkyl Halides with Vinyl Arenes/Heteroarenes
Kurandina, Daria,Parasram, Marvin,Gevorgyan, Vladimir
supporting information, p. 14212 - 14216 (2017/10/13)
The first visible light-induced Pd-catalyzed Heck reaction of α-heteroatom substituted alkyl iodides and -bromides with vinyl arenes/heteroarenes has been developed. This transformation efficiently proceeds at room temperature and enables synthesis of valuable functionalized allylic systems, such as allylic silanes, boronates, germanes, stannanes, pivalates, phosphonates, phthalimides, and tosylates from the corresponding α-substituted methyl iodides. Notably, synthesis of the latter substrates failed under existing thermally induced Pd-catalyzed conditions, which highlights the importance of visible light for this transformation.
Amide and amine nucleophiles in polar radical crossover cycloadditions: Synthesis of γ-lactams and pyrrolidines
Gesmundo, Nathan J.,Grandjean, Jean-Marc M.,Nicewicz, David A.
supporting information, p. 1316 - 1319 (2015/03/14)
In this work we present a direct catalytic synthesis of γ-lactams and pyrrolidines from alkenes and activated unsaturated amides or protected unsaturated amines, respectively. Using a mesityl acridinium single electron photooxidant and a thiophenol cocata
Palladium-catalyzed direct arylation of allylamines with simple arenes
Lei, Yichao,Qiu, Ruiying,Zhang, Lingjuan,Xu, Conghui,Pan, Yixiao,Qin, Xubo,Li, Huanrong,Xu, Lijin,Deng, Yuheng
, p. 1275 - 1279 (2015/04/27)
The Pd(OAc)2-catalyzed direct C-H bond olefination of unreactive arenes with allylamines in the presence of AgOAc was developed. A variety of allylamines including β-substituted substrates underwent smooth coupling reactions with various arenes
