87488-84-4Relevant academic research and scientific papers
Rhodium-Catalyzed Dealkenylative Arylation of Alkenes with Arylboronic Compounds
Das, Mowpriya,Glorius, Frank,Maisuls, Iván,Strassert, Cristian A.,Tan, Guangying
supporting information, p. 15650 - 15655 (2021/06/08)
The C?C bond formation reaction represents a fundamental and important transformation in synthetic chemistry, and exploring new types of C?C bond formation reactions is recognized as appealing, yet challenging. Herein, we disclose the first example of rhodium-catalyzed dealkenylative arylation of alkenes with arylboronic compounds, thereby providing an unconventional access to bi(hetero)aryls with excellent chemoselectivity. In this method, C(aryl)?C(alkenyl) and C(alkenyl)?C(alkenyl) bonds in various alkenes and 1,3-dienes can be cleaved via a hydrometalation and followed by β-carbon elimination pathway for Suzuki–Miyaura reactions. Furthermore, a series of novel organic fluorescent molecules with excellent photophysical properties has been efficiently constructed with this protocol.
Catalytic, Directed C-C Bond Functionalization of Styrenes
Onodera, Shunsuke,Togashi, Ryo,Ishikawa, Soya,Kochi, Takuya,Kakiuchi, Fumitoshi
supporting information, p. 7345 - 7349 (2020/08/19)
A method for catalytic conversion of C(aryl)-C(alkenyl) bonds in styrene derivatives to new C-C bonds is developed. In the presence of a rhodium catalyst, the alkenyl groups of styrenes bearing a pyrazolyl directing group were efficiently converted to other carbon substituents upon reacting with various alkenes including styrenes, aliphatic alkenes, and allyl alcohols. It is also indicated that the C-C bond cleavage proceeded via a hydrometalation/β-carbon elimination pathway.
Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication
Huang, He,Strater, Zack M.,Rauch, Michael,Shee, James,Sisto, Thomas J.,Nuckolls, Colin,Lambert, Tristan H.
supporting information, p. 13318 - 13322 (2019/08/12)
Visible-light photocatalysis and electrocatalysis are two powerful strategies for the promotion of chemical reactions. Here, these two modalities are combined in an electrophotocatalytic oxidation platform. This chemistry employs a trisaminocyclopropenium (TAC) ion catalyst, which is electrochemically oxidized to form a cyclopropenium radical dication intermediate. The radical dication undergoes photoexcitation with visible light to produce an excited-state species with oxidizing power (3.33 V vs. SCE) sufficient to oxidize benzene and halogenated benzenes via single-electron transfer (SET), resulting in C?H/N?H coupling with azoles. A rationale for the strongly oxidizing behavior of the photoexcited species is provided, while the stability of the catalyst is rationalized by a particular conformation of the cis-2,6-dimethylpiperidine moieties.
Synthesis of pyrrolo[1,2-a] quinolines and ullazines by visible light mediated one- and twofold annulation of N-arylpyrroles with arylalkynes
Das, Amrita,Ghosh, Indrajit,K?nig, Burkhard
supporting information, p. 8695 - 8698 (2016/07/15)
1-(2-Bromophenyl)-1H-pyrrole and 1-(2,6-dibromophenyl)-1H-pyrrole react in the presence of catalytic amounts of rhodamine 6G (Rh-6G) and N,N-diisopropylethylamine (DIPEA) under blue light irradiation with aromatic alkynes and subsequently cyclize intramol
Catalyst-free N-arylation using unactivated fluorobenzenes
Diness, Frederik,Fairlie, David P.
supporting information; experimental part, p. 8012 - 8016 (2012/09/05)
Caught in a 'SNAr'e: A one-step, high-yielding, catalyst-free method is described for N-arylation of azoles and indoles from unactivated monofluorobenzenes. This SNAr reaction tolerates a wide range of substituents and can also generate halogenated N-aryl products. The reaction can also be performed simultaneously with or subsequent to a copper- or palladium-catalyzed cross-coupling reaction in the same pot. Copyright
Preparation, properties, and reactivity of carbonylrhodium(I) complexes of di(2-pyrazolylaryl)amido-pincer ligands
Wanniarachchi, Sarath,Liddle, Brendan J.,Lindeman, Sergey V.,Gardinier, James R.
experimental part, p. 3623 - 3636 (2011/12/02)
A series of six carbonylrhodium(I) complexes of three new and three previously reported di(2-3R-pyrazolyl)-p-Z/X-aryl)amido pincer ligands, ( RZX)Rh(CO), (R is the substituent at the 3-pyrazolyl position proximal to the metal; Z and X are the aryl substituents para- to the arylamido nitrogen) were prepared. The metal complexes were studied to assess how their properties and reactivities can be tuned by varying the groups along the ligand periphery and how they compared to other known carbonylrhodium(I) pincer derivatives. This study was facilitated by the discovery of a new CuI-catalyzed coupling reaction between 2-(pyrazolyl)-4-X-anilines (X = Me or CF3) and 2-bromoaryl-1H-pyrazoles that allow the fabrication of pincer ligands with two different aryl arms. The NNN-pincer scaffolds provide an electron-rich environment for the carbonylrhodium(I) fragment as indicated by carbonyl stretching frequencies that occur in the range of 1948-1968 cm-1. As such, the oxidative addition (OA) reactions with iodomethane proceed instantaneously to form trans-(NNN-pincer)Rh(Me)(CO)(I) in room temperature acetone solution. The OA reactions with iodoethane proceeded at a convenient rate in acetone near 45 °C which allowed detailed kinetic studies. The relative order of reactivity was found to be (CF3CF 3)Rh(CO) iPrMeMe)Rh(CO) MeMeMe) Rh(CO) ～ (CF3Me)Rh(CO) 2 = 8 × 10-3 M-1 s-1, being about three orders of magnitude greater than those reported for [Rh(CO)2I 2]- or CpRh(CO)(PPh3). After oxidative addition, the resultant rhodium(III) complexes were found to be unstable. Although a few trans-(RMeMe)Rh(E = Me, Et, or I)(CO)(I) could be isolated in pure form, all were found to slowly decompose in solution to give different products depending on the 3R-pyrazolyl substituents. Those with unsubstituted pyrazolyls (R = H) decompose with CO dissociation to give insoluble dimeric [(RMeMe)Rh(E)(μ-I)]2 while those with 3-alkylpyrazolyls (R = Me, iPr) decompose to give soluble, but unidentified products.
Complete assignment of NMR data of 22 phenyl-1H-pyrazoles' derivatives
De Oliveira, Aline Lima,Alves De Oliveira, Carlos Henrique,Mairink, Laura Maia,Pazini, Francine,Menegatti, Ricardo,Liao, Luciano Morais
scheme or table, p. 537 - 542 (2011/10/09)
Complete assignment of 1H and 13C NMR chemical shifts and J(1H/1H and 1H/19F) coupling constants for 22 1-phenyl-1H-pyrazoles' derivates were performed using the concerted application of 1H 1D and 1H, 13C 2D gs-HSQC and gs-HMBC experiments. All 1-phenyl-1H-pyrazoles' derivatives were synthesized as described by Finar and co-workers. The formylated 1-phenyl-1H-pyrazoles' derivatives were performed under Duff's conditions. Copyright
