456-27-9Relevant articles and documents
Application of visible light photocatalysis with particle lithography to generate polynitrophenylene nanostructures
Verberne-Sutton, Susan D.,Quarels, Rashanique D.,Zhai, Xianglin,Garno, Jayne C.,Ragains, Justin R.
, p. 14438 - 14444 (2014)
Visible light photoredox catalysis was combined with immersion particle lithography to prepare polynitrophenylene organic films on Au(111) surfaces, forming a periodic arrangement of nanopores. Surfaces masked with mesospheres were immersed in solutions of p-nitrobenzenediazonium tetrafluoroborate and irradiated with blue LEDs in the presence of the photoredox catalyst Ru(bpy)3(PF6)2 to produce p-nitrophenyl radicals that graft onto gold substrates. Surface masks of silica mesospheres were used to protect small, discrete regions of the Au(111) surface from grafting. Nanopores were formed where the silica mesospheres touched the surface; the mask effectively protected nanoscopic local areas from the photocatalysis grafting reaction. Further reaction of the grafted arenes with aryl radicals resulted in polymerization to form polynitrophenylene structures with thicknesses that were dependent on both the initial concentration of diazonium salt and the duration of irradiation. Photoredox catalysis with visible light provides mild, user-friendly conditions for the reproducible generation of multilayers with thicknesses ranging from 2 to 100 nm. Images acquired with atomic force microscopy (AFM) disclose the film morphology and periodicity of the polymer nanostructures. The exposed sites of the nanopores provide a baseline to enable local measurements of film thickness with AFM. The resulting films of polynitrophenylene punctuated with nanopores provide a robust foundation for further chemical steps. Spatially selective binding of mercaptoundecanoic acid to exposed sites of Au(111) was demonstrated, producing a periodic arrangement of thiol-based nanopatterns within a matrix of polynitrophenylene.
Chirality-Selective Functionalization of Semiconducting Carbon Nanotubes with a Reactivity-Switchable Molecule
Powell, Lyndsey R.,Kim, Mijin,Wang, Yuhuang
, p. 12533 - 12540 (2017)
Chirality-selective functionalization of semiconducting single-walled carbon nanotubes (SWCNTs) has been a difficult synthetic goal for more than a decade. Here we describe an on-demand covalent chemistry to address this intriguing challenge. Our approach
Evidence for covalent bonding of aryl groups to MnO2 nanorods from diazonium-based grafting
Bell,Brooksby,Polson,Downard
, p. 13687 - 13690 (2014)
We show here that the surface of MnO2 nanorods can be modified with aryl groups by grafting from aqueous and non-aqueous solutions of aryldiazonium salts. X-ray photoelectron spectroscopy provides direct evidence for covalent bonding of aryl groups to MnO2 through surface oxygens.
Azoacetylenes for the Synthesis of Arylazotriazole Photoswitches
Anderl, Felix,Balkenhohl, Moritz,Carreira, Erick M.,Fink, Moritz,Pfaff, Patrick
supporting information, p. 14495 - 14501 (2021/09/18)
We report a modular approach toward novel arylazotriazole photoswitches and their photophysical characterization. Addition of lithiated TIPS-acetylene to aryldiazonium tetrafluoroborate salts gives a wide range of azoacetylenes, constituting an underexplored class of stable intermediates.In situdesilylation transiently leads to terminal arylazoacetylenes that undergo copper-catalyzed cycloadditions (CuAAC) with a diverse collection of organoazides. These include complex molecules derived from natural products or drugs, such as colchicine, taxol, tamiflu, and arachidonic acid. The arylazotriazoles display near-quantitative photoisomerization and long thermalZ-half-lives. Using the method, we introduce for the first time the design and synthesis of a diacetylene platform. It permits implementation of consecutive and diversity-oriented approaches linking two different conjugants to independently addressable acetylenes within a common photoswitchable azotriazole. This is showcased in the synthesis of several photoswitchable conjugates, with potential applications as photoPROTACs and biotin conjugates.
Base-Free Cross-Couplings of Aryl Diazonium Salts in Methanol: PdII–Alkoxy as Reactivity-Controlling Intermediate
Sanhueza, Italo A.,Klauck, Felix J. R.,Senol, Erdem,Keaveney, Sinead T.,Sperger, Theresa,Schoenebeck, Franziska
, p. 7007 - 7012 (2021/03/01)
Pd-catalyzed cross-coupling reactions of aryl diazonium salts are generally assumed to proceed via cationic PdII intermediates which in turn would be highly reactive in the subsequent transmetalation step. Contrary to this belief, we herein report our observation and rationalization of opposing reactivities of ArN2+ in Suzuki (=effective) and Stille (=ineffective) cross-couplings in MeOH. Our systematic experimental and computational studies on the roles of transmetalating agent, solvent, base and the likely involvement of in situ formed diazoether derivatives challenge the currently accepted mechanism. Our data suggest that the observed solvent dichotomy is primarily due to PdII-methoxy intermediates being formed, which are unreactive with arylstannanes, but highly reactive with arylboronic acids, complementing the Suzuki “Pd-oxy” mechanism with the direct demonstration of transmetalation of a PdII-alkoxy complex. Lewis acids were found to circumvent this reactivity divergence, promoting efficient couplings regardless of the employed conditions or coupling partners.
Alternative method for the synthesis of triazenes from aryl diazonium salts
Abrams
supporting information, (2021/05/10)
An alternative mild method for access to 1-aryl-3,3-dimethyl alkyl triazenes is described. This protocol employs the dropwise addition of a methanolic solution of a carboxylate (RCO2M) or carbonate (CO32?) to a gently heated DMF solution containing an aryl diazonium salt (ArN2+), that had been previously isolated. Presumably homolysis of the weak N–O bond of diazo ether adducts formed in this operation initiates radical pathways that lead to the generation of triazene product. DMF serves as not only a one-electron donor to the diazonium salts employed in this process, but also as a source of dimethylamine radicals that act as a nucleophilic coupling partner. The reaction provides modest yields (ca. 20–40%) across an array of aryl diazonium salts that contain various substitution. Furthermore this unique approach to triazenes contrasts with traditional methods that employ dimethyl amine in reagent form which directly couples with diazonium salts. Seemingly, only one other example employing somewhat similar reaction conditions to this current investigation en route to triazenes has been reported, albeit with lower yields and for one representative example furnished as a side-product. The current work here improves upon the efficiency of this reported result, and further expands the reaction scope.
Aqueous and Visible-Light-Promoted C-H (Hetero)arylation of Uracil Derivatives with Diazoniums
Liu, An-Di,Wang, Zhao-Li,Liu, Li,Cheng, Liang
, p. 16434 - 16447 (2021/11/16)
Direct C5 (hetero)arylation of uracil and uridine substrates with (hetero)aryl diazonium salts under photoredox catalysis with blue light was reported. The coupling proceeds efficiently with diazonium salts and heterocycles in good functional group tolerance at room temperature in aqueous solution without transition-metal components. A plausible radical mechanism has been proposed.
Metal-Free Visible-Light Synthesis of Arylsulfonyl Fluorides: Scope and Mechanism
Louvel, Dan,Chelagha, Aida,Rouillon, Jean,Payard, Pierre-Adrien,Khrouz, Lhoussain,Monnereau, Cyrille,Tlili, Anis
supporting information, p. 8704 - 8708 (2021/05/17)
The first metal-free procedure for the synthesis of arylsulfonyl fluorides is reported. Under organo-photoredox conditions, aryl diazonium salts react with a readily available SO2 source (DABSO) to afford the desired product through simple nucleophilic fluorination. The reaction tolerates the presence of both electron-rich and -poor aryls and demonstrated a broad functional group tolerance. To shed the light on the reaction mechanism, several experimental techniques were combined, including fluorescence, NMR, and EPR spectroscopy as well as DFT calculations.
Gold(I)-Catalyzed Cross-Coupling Reactions of Arenediazonium Salts with Alkynoic Acids
Abrams, J. N.,Chi, B. K.
, p. 1236 - 1244 (2020/09/17)
Abstract: The reaction of simple alkynoate salts with isolated arenediazonium tetrafluoroborate salts that had been pre-conditioned with the gold(I) catalyst AuCl(Me2S) led to the formation of cross-coupled products via a decarboxylative Sonogashira reaction process in modest yield and under mild conditions. The major by-product is a defunctionalized aryl moiety stemming from the diazonium salt, which competitively forms via hydrodediazonation. Good functional group tolerance and reaction site selectivity were attained in this limited investigation.
Discovery and structure-activity relationship studies of 1-aryl-1H-naphtho[2,3-d][1,2,3]triazole-4,9-dione derivatives as potent dual inhibitors of indoleamine 2,3-dioxygenase 1 (IDO1) and trytophan 2,3-dioxygenase (TDO)
Pan, Shulei,Zhou, Yangli,Wang, Qiusheng,Wang, Yanlin,Tian, Chenyu,Wang, Tianqi,Huang, Luyi,Nan, Jinshan,Li, Linli,Yang, Shengyong
, (2020/09/01)
Indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan 2,3-dioxygenase (TDO), which mediate kynurenine pathway of tryptophan degradation, have emerged as potential new targets in immunotherapy for treatment of cancer because of their critical role in immunosuppression in the tumor microenvironment. In this investigation, we report the structural optimization and structure-activity relationship studies of 1-phenyl-1H-naphtho[2,3-d][1,2,3]triazole-4,9-dione derivatives as a new class of IDO1/TDO dual inhibitors. Among all the obtained dual inhibitors, 1-(3-chloro-4-fluorophenyl)-6-fluoro-1H-naphtho[2,3-d][1,2,3]triazole-4,9-dione (38) displayed the most potent IDO1 and TDO inhibitory activities with IC50 (half-maximal inhibitory concentration) values of 5 nM for IDO1 and 4 nM for TDO. It turned out that compound 38 was not a PAINS compound. Compound 38 could efficiently inhibit the biofunction of IDO1 and TDO in intact cells. In LL2 (Lewis lung cancer) and Hepa1-6 (hepatic carcinoma) allograft mouse models, this compound also showed considerable in vivo anti-tumor activity and no obvious toxicity was observed. Therefore, 38 could be a good lead compound for cancer immunotherapy and deserving further investigation.
