32664-13-4Relevant academic research and scientific papers
Copper Photosensitizers Containing P^N Ligands and Their Influence on Photoactivity and Stability
Giereth, Robin,Frey, Wolfgang,Junge, Henrik,Tschierlei, Stefanie,Karnahl, Michael
, p. 17432 - 17437 (2017)
Driven by the intention to improve classic heteroleptic copper photosensitizers two novel Cu(I) complexes applying a hetero-bidentate P^N ligand were prepared. A combined photophysical, electrochemical, and theoretical study gives insights into structure–activity relationships and revealed an increased absorptivity. Both complexes were tested for the light-driven production of H2.
Copper(I) Phosphinooxazoline Complexes: Impact of the Ligand Substitution and Steric Demand on the Electrochemical and Photophysical Properties
Frey, Wolfgang,Giereth, Robin,Karnahl, Michael,Klo?, Marvin,Mengele, Alexander K.,Steffen, Andreas,Tschierlei, Stefanie
, p. 2675 - 2684 (2020/03/04)
A series of seven homoleptic CuI complexes based on hetero-bidentate P^N ligands was synthesized and comprehensively characterized. In order to study structure–property relationships, the type, size, number and configuration of substituents at the phosphinooxazoline (phox) ligands were systematically varied. To this end, a combination of X-ray diffraction, NMR spectroscopy, steady-state absorption and emission spectroscopy, time-resolved emission spectroscopy, quenching experiments and cyclic voltammetry was used to assess the photophysical and electrochemical properties. Furthermore, time-dependent density functional theory calculations were applied to also analyze the excited state structures and characteristics. Surprisingly, a strong dependency on the chirality of the respective P^N ligand was found, whereas the specific kind and size of the different substituents has only a minor impact on the properties in solution. Most importantly, all complexes except C3 are photostable in solution and show fully reversible redox processes. Sacrificial reductants were applied to demonstrate a successful electron transfer upon light irradiation. These properties render this class of photosensitizers as potential candidates for solar energy conversion issues.
Sulfoxide ligand metal catalyzed oxidation of olefins
-
, (2019/05/09)
The enantioselective synthesis of isochroman motifs has been accomplished via Pd(II)-catalyzed allylic C—H oxidation from terminal olefin precursors. Critical to the success of this goal was the development and utilization of a novel chiral aryl sulfoxide-oxazoline (ArSOX) ligand. The allylic C—H oxidation reaction proceeds with the broadest scope and highest levels asymmetric induction reported to date (avg. 92% ee, 13 examples ≥90% ee). Additionally, C(sp3)-N fragment coupling reaction between abundant terminal olefins and N-triflyl protected aliphatic and aromatic amines via Pd(II)/sulfoxide (SOX) catalyzed intermolecular allylic C—H amination is disclosed. A range of 52 allylic amines are furnished in good yields (avg. 76%) and excellent regio- and stereoselectivity (avg. >20:1 linear:branched, >20:1 E:Z). For the first time, a variety of singly activated aromatic and aliphatic nitrogen nucleophiles, including ones with stereochemical elements, can be used in fragment coupling stiochiometries for intermolecular C—H amination reactions.
Discovery of Novel Naphthylphenylketone and Naphthylphenylamine Derivatives as Cell Division Cycle 25B (CDC25B) Phosphatase Inhibitors: Design, Synthesis, Inhibition Mechanism, and in Vitro Efficacy against Melanoma Cell Lines
Cerchia, Carmen,Nasso, Rosarita,Mori, Matteo,Villa, Stefania,Gelain, Arianna,Capasso, Alessandra,Aliotta, Federica,Simonetti, Martina,Rullo, Rosario,Masullo, Mariorosario,De Vendittis, Emmanuele,Ruocco, Maria Rosaria,Lavecchia, Antonio
, p. 7089 - 7110 (2019/08/20)
CDC25 phosphatases play a critical role in the regulation of the cell cycle and thus represent attractive cancer therapeutic targets. We previously discovered the 4-(2-carboxybenzoyl)phthalic acid (NSC28620) as a new CDC25 inhibitor endowed with promising anticancer activity in breast, prostate, and leukemia cells. Herein, we report a structure-based optimization of NSC28620, leading to the identification of a series of novel naphthylphenylketone and naphthylphenylamine derivatives as CDC25B inhibitors. Compounds 7j, 7i, 6e, 7f, and 3 showed higher inhibitory activity than the initial lead, with Ki values in the low micromolar range. Kinetic analysis, intrinsic fluorescence studies, and induced fit docking simulations provided a mechanistic understanding of the activity of these derivatives. All compounds were tested in the highly aggressive human melanoma cell lines A2058 and A375. Compound 4a potently inhibited cell proliferation and colony formation, causing an increase of the G2/M phase and a reduction of the G0/G1 phase of the cell cycle in both cell lines.
C-H to C-N Cross-Coupling of Sulfonamides with Olefins
Ma, Rulin,Christina White
, p. 3202 - 3205 (2018/03/13)
Cross-coupling of nitrogen with hydrocarbons under fragment coupling conditions stands to significantly impact chemical synthesis. Herein, we disclose a C(sp3)-N fragment coupling reaction between terminal olefins and N-triflyl protected aliphatic and aromatic amines via Pd(II)/SOX (sulfoxide-oxazoline) catalyzed intermolecular allylic C-H amination. A range of (56) allylic amines are furnished in good yields (avg. 75%) and excellent regio- and stereoselectivity (avg. >20:1 linear:branched, >20:1 E:Z). Mechanistic studies reveal that the SOX ligand framework is effective at promoting functionalization by supporting cationic π-allyl Pd.
Palladium-catalyzed electrophilic C–H fluorination of arenes using oxazoline as a removable directing group
Gutierrez, David A.,Lee, Wan-Chen Cindy,Shen, Yuning,Li, Jie Jack
supporting information, p. 5372 - 5376 (2016/11/11)
Dimethyloxazoline was rationally designed to act as a removable ortho-directing group (DG) for the palladium-catalyzed C–H electrophilic fluorination of arenes. Using NFSI as the fluorinating agent, and Pd(II), Ag(I) catalytic system, electrophilic C(sp2–H) ortho-fluorination took place on a variety of aryl substrates to afford the corresponding mono- and di-fluorinated products.
Group exchange between ketones and carboxylic acids through directing group assisted Rh-catalyzed reorganization of carbon skeletons
Lei, Zhi-Quan,Pan, Fei,Li, Hu,Li, Yang,Zhang, Xi-Sha,Chen, Kang,Wang, Xin,Li, Yu-Xue,Sun, Jian,Shi, Zhang-Jie
supporting information, p. 5012 - 5020 (2015/05/05)
The Rh(I)-catalyzed direct reorganization of organic frameworks and group exchanges between carboxylic acids and aryl ketones was developed with the assistance of directing group. Biaryls, alkenylarenes, and alkylarenes were produced in high efficiency from aryl ketones and the corresponding carboxylic acids by releasing the other molecule of carboxylic acids and carbon monoxide. A wide range of functional groups were well compatible. The exchanges between two partners were proposed to take place on the Rh-(III) center of key intermediates, supported by experimental mechanistic studies and computational calculations. The transformation unveiled the new catalytic pathway of the group transfer of two organic molecules.
Directed functionalization of halophenyl-2-oxazolines with TMPMgCl?LiCl
Batista, Joo H. C.,Santos, Fernanda M. Dos,Bozzini, Leandro A.,Vessecchi, Ricardo,Oliveira, Alfredo R. M.,Clososki, Giuliano C.
, p. 967 - 977 (2015/02/19)
A variety of difunctionalized aryl-2-oxazolines were prepared from the reaction of halophenyl-2-oxazolines and TMPMgCl?LiCl to give an organomagnesium reagent, which was then treated with various electrophiles. The metalation step takes place under mild conditions, and this process al-lows for the isolation of the desired products in good yields. No isomeric or other benzyne-derived products were detected. The influence of the halogen substituents on the acidity of the aromatic hydrogen atoms was evaluated by using density functional theory (DFT) calculations.
Bidentate cycloimidate palladium complexes with aliphatic and aromatic anagostic bonds
Sch?ler, Stephan,Wahl, Maike H.,Wurster, Nicole I. C.,Puls, Arik,H?ttig, Christof,Dyker, Gerald
, p. 5909 - 5911 (2014/05/20)
Palladium(ii) complexes of bidentate cycloimidate ligand systems with a triarylmethyl moiety exhibit exceptional downfield shifts in proton NMR spectra due to rare anagostic interactions. This journal is the Partner Organisations 2014.
Synthesis of 4-oxazolinephenylboronic acid and heterobiaryl oxazolines via a Suzuki reaction
Ghosh, Samir,Kumar, A.Sanjeev,Mehta,Soundararajan,Sen, Subhabrata
scheme or table, p. 205 - 207 (2009/11/30)
An efficient synthesis of 4-oxazolinephenylboronic acid from 4-bromobenzoic acid is reported. The title compound couples with heteroaryl halides in presence of Pd(PPh3)4 and Na2CO3 in aqueous toluene to give het
