15359-99-6Relevant academic research and scientific papers
Urea-based organocatalyst catalyzed direct C–H bond arylations of unactivated arenes
Zhao, Huaiqing,Xu, Xiangwen,Wu, Wei,Zhang, Wei,Zhang, Yunxian
, p. 95 - 99 (2018/04/24)
A simple 1,3-diethylurea was demonstrated to catalyze transition-metal-free arylations of unactivated aromatic C–H bonds with aryl iodides in the presence of t-BuOK. A broad range of aryl iodides with different arenes could couple in moderate to excellent yields. The mechanistic experiment results indicated that the radical is involved in this transformation.
A study of diketopiperazines as electron-donor initiators in transition metal-free haloarene-arene coupling
Cumine, Florimond,Zhou, Shengze,Tuttle, Tell,Murphy, John A.
, p. 3324 - 3336 (2017/04/21)
Several diketopiperazines have been shown to promote carbon-carbon coupling between benzene and aryl halides in the presence of potassium tert-butoxide and without the assistance of a transition metal catalyst. The structure of the diketopiperazine has an influence on its reductive potential and can help to promote the coupling of the more challenging aryl bromides with benzene.
Iron-mediated direct arylation of unactivated arenes in air
Huang, Yuxing,Moret, Marc-Etienne,Klein Gebbink, Robertus J. M.
supporting information, p. 3788 - 3793 (2014/06/24)
Biaryls are a common motif in both natural and synthetic chemicals. Several methods have recently been reported for the preparation of these compounds using direct arylation catalyzed by iron, other base metals, or transition-metal-free systems. To date, these methods have all required inert and/or forcing conditions, which limited their application in routine organic synthesis. In this article we report a protocol for direct arylation using a convenient FeCl3/1,10-phenanthroline system as precatalyst. The reaction proceeds under mild conditions (100 °C), under air, and with non-distilled solvent. A simple, environmentally benign catalytic system based on iron trichloride and phenanthroline has been developed for the direct arylation of unactivated arenes with aryl halides under air. Copyright
Practical synthesis of aromatic ethers by SNAr of fluorobenzenes with alkoxides
Rodriguez, Juan R.,Agejas, Javier,Bueno, Ana B.
, p. 5661 - 5663 (2007/10/03)
Aromatic fluorines have been substituted by alkoxides in a variety of activated and unactivated aromatic systems.
Catalyst for aromatic C—O, C—N, and C—C bond formation
-
, (2008/06/13)
The present invention is directed to a transition metal catalyst, comprising a Group 8 metal and a ligand having the structure wherein R, R′ and R″ are organic groups having 1-15 carbon atoms, n=1-5, and m=0-4. The present invention is also directed to a method of forming a compound having an aromatic or vinylic carbon-oxygen, carbon-nitrogen, or carbon-carbon bond using the above catalyst. The catalyst and the method of using the catalyst are advantageous in preparation of compounds under mild conditions of approximately room temperature and pressure.
Air stable, sterically hindered ferrocenyl dialkylphosphines for palladium-catalyzed C-C, C-N, and C-O bond-forming cross-couplings
Kataoka, Noriyasu,Shelby, Quinetta,Stambuli, James P.,Hartwig, John F.
, p. 5553 - 5566 (2007/10/03)
Pentaphenylferrocenyl di-tert-butylphosphine has been prepared in high yield from a two-step synthetic procedure, and the scope of various cross-coupling processes catalyzed by complexes bearing this ligand has been investigated. This ligand creates a remarkably general palladium catalyst for aryl halide amination and for Suzuki coupling. Turnovers of roughly 1000 were observed for aminations with unactivated aryl bromides or chlorides. In addition, complexes of this ligand catalyzed the formation of selected aryl ethers under mild conditions. The reactions encompassed electron-rich and electron-poor aryl bromides and chlorides. In the presence of catalysts containing this ligand, these aryl halides coupled with acyclic or cyclic secondary alkyl- and arylamines, with primary alkyl- and arylamines, and with aryl- and primary alkylboronic acids. These last couplings provide the first general procedure for reaction of terminal alkylboronic acids with aryl halides without toxic or expensive bases. The ligand not only generates highly active palladium catalysts, but it is air stable in solution and in the solid state. Palladium(0) complexes of this ligand are also air stable as a solid and react only slowly with oxygen in solution.
Palladium/P(t-Bu)3-catalyzed synthesis of aryl t-butyl ethers and application to the first synthesis of 4-chlorobenzofuran
Watanabe, Makoto,Nishiyama, Masakazu,Koie, Yasuyuki
, p. 8837 - 8840 (2007/10/03)
Pd/P(t-Bu)3 catalyzed reaction of aryl halides with sodium t-butoxide effectively to give aryl t-butyl ethers. The high catalytic activity realized the formation of aryl t-butyl ethers from not only electron-deficient aryl halides but also electron-rich aryl halides. Moreover, the first synthesis of 4-chlorobenzofuran was attained utilizing the selective mono-t-butoxylation of aryl dihalide.
Photodehalogenation of the Monochloro- and Monofluoroanisoles
Siegman, John R.,Houser, John J.
, p. 2773 - 2779 (2007/10/02)
Evidence is presented for a plurality of mechanisms in the photoreduction and photonucleophilic substitution of the monochloroanisoles in alcohol solvents. 4-Chloroanisole appears to react partly via a radical anion and partly by radicals, while the reactions of 3-chloroanisole are more consistent with aryl cations and aryl radicals.The intermediates in the reaction of 2-chloroanisole, which gives no photosubstitution, are as yet not identified but are probably not radical anions.In the case of 4-chloroanisole, substitution and reduction may proceed from different states.Preliminary results on the fluoroanisoles show the 2-F isomer giving both reduction and substitution and the 3- and 4-F isomers only substitution.
