4373-67-5Relevant academic research and scientific papers
Decarbonylative Pd-Catalyzed Suzuki Cross-Coupling for the Synthesis of Structurally Diverse Heterobiaryls
Blakemore, David C.,Cervantes-Reyes, Alejandro,Chinigo, Gary M.,Smith, Aaron C.,Szostak, Michal
supporting information, p. 1678 - 1683 (2022/03/14)
Heteroaromatic biaryls are core scaffolds found in a plethora of pharmaceuticals; however, their direct synthesis by the Suzuki cross-coupling is limited to heteroaromatic halide starting materials. Here, we report a direct synthesis of diverse nitrogen-containing heteroaromatic biaryls by Pd-catalyzed decarbonylative Suzuki cross-coupling of widely available heterocyclic carboxylic acids with arylboronic acids. The practical and modular nature of this cross-coupling enabled the straightforward preparation of >45 heterobiaryl products using pyridines, pyrimidines, pyrazines, and quinolines in excellent yields. We anticipate that the modular nature of this protocol will find broad application in medicinal chemistry and drug discovery research.
Carbon Atom Insertion into Pyrroles and Indoles Promoted by Chlorodiazirines
Dherange, Balu D.,Kelly, Patrick Q.,Levin, Mark D.,Liles, Jordan P.,Sigman, Matthew S.
supporting information, p. 11337 - 11344 (2021/08/16)
Herein, we report a reaction that selectively generates 3-arylpyridine and quinoline motifs by inserting aryl carbynyl cation equivalents into pyrrole and indole cores, respectively. By employing α-chlorodiazirines as thermal precursors to the corresponding chlorocarbenes, the traditional haloform-based protocol central to the parent Ciamician-Dennstedt rearrangement can be modified to directly afford 3-(hetero)arylpyridines and quinolines. Chlorodiazirines are conveniently prepared in a single step by oxidation of commercially available amidinium salts. Selectivity as a function of pyrrole substitution pattern was examined, and a predictive model based on steric effects is put forward, with DFT calculations supporting a selectivity-determining cyclopropanation step. Computations surprisingly indicate that the stereochemistry of cyclopropanation is of little consequence to the subsequent electrocyclic ring opening that forges the pyridine core, due to a compensatory homoaromatic stabilization that counterbalances orbital-controlled torquoselectivity effects. The utility of this skeletal transform is further demonstrated through the preparation of quinolinophanes and the skeletal editing of pharmaceutically relevant pyrroles.
N-heterocyclic carbene coordinated heterogeneous Pd nanoparticles as catalysts for suzuki-miyaura coupling
Min, Hyemin,Miyamura, Hiroyuki,Kobayashi, Shu
supporting information, p. 837 - 839 (2016/07/16)
Palladium nanoparticle (Pd NP) catalysts immobilized in a polymer with an N-heterocyclic carbene (NHC) moiety (PICBNHC-Pd) have been developed, wherein the NHC moiety plays dual roles as a crosslinker and a ligand to activate the Pd NPs. The presence of both Pd NPs and NHC was confirmed by STEM/EDS and SR-MAS NMR analyses, respectively. This PICB-NHC-Pd catalyst showed excellent activity in the Suzuki-Miyaura coupling reaction without leaching of Pd. Excellent results were obtained in gram-scale synthesis, and catalyst recovery/reuse experiments were completed without loss of catalyst activity.
Synthesis of 3-Arylpyridines via Palladium/Copper-Catalyzed Annulation of Allylamine/1,3-Propanediamine and Aldehydes
Yang, Xiaodong,Yang, Shenghua,Xiang, Likui,Pang, Xiaobo,Chen, Baohua,Huang, Guosheng,Yan, Rulong
, p. 3732 - 3736 (2016/01/25)
A novel and efficient method for the synthesis of 3-arylpyridines from allylamine/propanediamine and aldehydes by palladium/copper-catalyzed oxidative tandem cyclization has been developed. With this reaction, a series of desired 3-arylpyridines was synthesized in moderate yields via C-C/C-N bond formation and 6-endo/exo-trig cyclization.
Very efficient and broad-in-scope palladium-catalyzed Hiyama cross-coupling. the role of water and copper(I) salts
Traficante, Carla I.,Mata, Ernesto G.,Delpiccolo, Carina M. L.
, p. 26796 - 26800 (2015/03/30)
A very high-yielding Pd-catalyzed cross-coupling between aryl halides and aryl(trialkoxy)silanes is achieved in the presence of Cu(i) and a measured amount of water. This novel methodology is useful for the generation of a wide range of biaryls, particularly non-para substituted derivatives, which are usually less reported.
Palladium-catalyzed decarboxylative cross-coupling of 3-pyridyl and 4-pyridyl carboxylates with aryl bromides
Chennamaneni, Lohitha Rao,William, Anthony D.,Johannes, Charles W.
, p. 1293 - 1296 (2015/03/04)
Decarboxylative cross-coupling of 3-pyridyl and 4-pyridyl carboxylates with aryl bromides is reported. Using a bimetallic system of Cu2O and Pd(PPh3)4, the scope of the reaction is demonstrated by the synthesis of 27 pyridine-containing biaryls in moderate to good yields.
Cross-coupling study of iodo/chloropyridines and 2-chloroquinoline with atom-economic triarylbismuth reagents under Pd-catalysis
Rao, Maddali L.N.,Dhanorkar, Ritesh J.
, p. 338 - 349 (2015/03/04)
This study describes the palladium-catalyzed couplings of iodopyridines, chloropyridines, and chloroquinoline with atom-economic BiAr3 reagents in sub-stoichiometric loadings. Mono-arylations of iodo and chloropyridines produced arylpyridines i
Triarylbismuthanes as threefold aryl-transfer reagents in regioselective cross-coupling reactions with bromopyridines and quinolines
Rao, Maddali L.N.,Dhanorkar, Ritesh J.
supporting information, p. 5214 - 5228 (2014/10/15)
Cross-coupling studies using bromopyridines and bromoquinolines with triarylbismuths as threefold coupling reagents in substoichiometric amounts under Pd-catalysed conditions are disclosed. The reactivity was high with both mono- and dibromopyridyl substrates, and mono- and bis-couplings were carried out regioselectively. A library of monoaryl and diaryl pyridines was formed in high yields. A one-pot strategy provided a simple and straightforward synthesis of both symmetrical and unsymmetrical diarylpyridines. Arylations of 2-bromo- and 3-bromoquinolines were achieved with triarylbismuth reagents. This study demonstrates that triarylbismuths may be used as threefold arylating reagents for the synthesis of aryl pyridines and quinolines through couplings with bromopyridines and bromoquinolines under Pd-catalysed conditions. Copyright
Rapid microwave-assisted sol-gel preparation of Pd-substituted LnFeO 3 (Ln = Y, La): Phase formation and catalytic activity
Misch, Lauren M.,Birkel, Alexander,Figg, C. Adrian,Fors, Brett P.,Hawker, Craig J.,Stucky, Galen D.,Seshadri, Ram
supporting information, p. 2079 - 2087 (2014/01/17)
We present a rapid microwave-assisted sol-gel approach to Pd-substituted LnFeO3 (Ln = Y, La) for applications in C-C coupling reactions. These materials could be prepared in household microwave ovens in less than 15 minutes of reaction time with the final materials displaying well-defined structure and morphology. Phase evolution was studied using time-dependent microwave heatings and then compared with the results obtained from thermogravimetric analyses. Materials were confirmed to be phase pure by laboratory and synchrotron X-ray diffraction. Substituted Pd is ionic as shown by the binding energy shift from X-ray photoelectron spectroscopy. The short heating periods required for phase purity allow these materials less time for sintering as compared to conventional solid state preparation methods, making relatively high surface areas achievable. These materials have been successfully used as catalyst precursor materials for C-C coupling reactions in which the active species is Pd0. Pd-substituted LnFeO3 (Ln = Y, La) provides Pd0 in solution which can be complexed by the ligand SPhos, allowing for aryl chloride coupling.
Synthesis of heteroaryl compounds through cross-coupling reaction of aryl bromides or benzyl halides with thienyl and pyridyl aluminum reagents
Chen, Xu,Zhou, Lingmin,Li, Yimei,Xie, Tao,Zhou, Shuangliu
, p. 230 - 239 (2014/01/17)
An efficient method for synthesis of useful biaryl building blocks containing 2-thienyl, 3-thienyl, 2-pyridyl, and 3-pyridyl moieties was provided through cross-coupling reactions of aryl bromides or benzyl halides with heteroaryl aluminum reagents in the presence of Pd(OAc)2 and (o-tolyl)3P. The coupling reaction also worked efficiently with heteroaryl bromides affording series of heterobiaryl compounds. The reaction of phenylbromide with in situ prepared 3-pyridyl aluminum was demonstrated to afford the product 8a in high yield. Additionally, the catalytic system was also suited well for the coupling reaction of benzyl halides with pyridyl aluminum reagents to afford series of pyridyl-arylmethane.
