18213-90-6Relevant articles and documents
Ruthenium-catalysedmeta-selective CAr-H bond alkylationviaa deaminative strategy
Zhu, Ze-Fan,Chen, Guang-Le,Liu, Feng
supporting information, p. 3411 - 3414 (2021/04/07)
The use of aliphatic amines as alkylating reagents in organic synthesisviaC-N bond activation remains underdeveloped. We herein describe a novel ruthenium-catalysed and directing-group assisted protocol for the synthesis ofmeta-alkylated arenesviadual C-H and C-N activation. Bench-stable and easily handled redox-active Katritzky pyridinium salts derived from abundant amines and amino acid species were used as alkyl radical precursors. This catalytic reaction could accommodate a broad range of functional groups and provide access to variousmeta-alkylated products.
Oxidative Dehydrosulfurative Carbon-Oxygen Cross-Coupling of 3,4-Dihydropyrimidine-2-thiones with Aryl Alcohols
Phan, Trong Nguyen Huu,Lee, Jihong,Shin, Hyunik,Sohn, Jeong-Hun
, p. 5423 - 5430 (2021/05/05)
A Pd-catalyzed/Cu-mediated oxidative dehydrosulfurative carbon-oxygen cross-coupling reaction of 3,4-dihydropyrimidin-1H-2-thiones (DHPMs) with aryl alcohols is described. Due to the ready availability of diverse DHPMs and aryl alcohols, the reaction method offers facile access to biologically and pharmacologically valuable 2-aryloxypyrimidine derivatives with rapid diversification.
Aerobic copper-promoted oxidative dehydrosulfurative carbon-oxygen cross-coupling of 3,4-dihydropyrimidine-1: H -2-thiones with alcohols
Kwon, Yujeong,Lee, Dong-Chan,Lee, Jihong,Sohn, Jeong-Hun
, p. 36821 - 36825 (2021/12/02)
An aerobic Cu-promoted oxidative dehydrosulfurative carbon-oxygen cross-coupling of 3,4-dihydropyrimidin-1H-2-thiones (DHPMs) with both aliphatic and aromatic alcohols is described. Together with the ready availability of DHPMs and both alcohols, the meth
A directing group-assisted ruthenium-catalyzed approach to access: Meta -nitrated phenols
Sasmal, Sheuli,Sinha, Soumya Kumar,Lahiri, Goutam Kumar,Maiti, Debabrata
supporting information, p. 7100 - 7103 (2020/07/14)
meta-Selective C-H nitration of phenol derivatives was developed using a Ru-catalyzed σ-activation strategy. Cu(NO3)2·3H2O was employed as the nitrating source, whereas Ru3(CO)12 was found to be the most suitable metal catalyst for the protocol. Mechanistic studies suggested involvement of an ortho-CAr-H metal intermediate, which promoted meta-electrophilic aromatic substitution and silver-assisted free-radical pathway.
Synthesis of m-Alkylphenols via a Ruthenium-Catalyzed C-H Bond Functionalization of Phenol Derivatives
Li, Gang,Gao, Panpan,Lv, Xulu,Qu, Chen,Yan, Qingkai,Wang, Ya,Yang, Suling,Wang, Junjie
supporting information, p. 2682 - 2685 (2017/05/24)
The first example of the synthesis of m-alkylphenols via a ruthenium-catalyzed CAr-H bond functionalization of phenol derivatives with sec/tert-alkyl bromides is reported. Mechanistic studies indicated that the m-CAr-H bond alkylation may involve a radical process and that a six-membered ruthenacycle complex was the active catalyst. Moreover, this approach can provide an expedited strategy for the atom-/step-economical synthesis of many noteworthy pharmaceuticals and other functional molecules.
Electrochemical intramolecular c-h amination: Synthesis of benzoxazoles and benzothiazoles
Morofuji, Tatsuya,Shimizu, Akihiro,Yoshida, Jun-Ichi
supporting information, p. 3211 - 3214 (2015/03/05)
A new method for metal-free intramolecular C-H amination has been developed. Electrochemical oxidation of 2-pyrimidyloxybenzenes and 2-pyrimidylthiobenzenes, which can be easily prepared from phenols and thiophenols, respectively, followed by the treatment of the resulting pyrimidinium ions with piperidine gives 2-aminobenzoxazoles and 2-aminobenzothiazoles, respectively.
An efficient method for the synthesis of heteroaryl C-O bonds in the absence of added transition metal catalysts
Walsh, Katie,Sneddon, Helen F.,Moody, Christopher J.
, p. 28072 - 28077 (2014/07/21)
Reaction of 2-chloropyrazine and 2-chloropyrimidine with phenols and alcohols in the presence of K2CO3 in DMSO results in high yielding SNAr coupling. The reaction works particularly well with phenols and yields are compar
Room temperature Ullmann type C-O and C-S cross coupling of aryl halides with phenol/thiophenol catalyzed by CuO nanoparticles
Babu, S. Ganesh,Karvembu
, p. 1677 - 1680 (2013/03/28)
C-O/C-S cross coupling of aryl halides with phenol or thiophenol was studied under ligand-free condition at room temperature over CuO nanocatalyst. The scope of the reaction was extended to various aryl halides and substituted phenols under optimized condition. In general, efficient, selective, and reusable heterogeneous nano CuO catalytic system has been developed for room temperature C-O and C-S Ullmann type cross coupling reactions.
Etherification of functionalized phenols with chloroheteroarenes at low palladium loading: Theoretical assessment of the role of triphosphane ligands in C-O reductive elimination
Platon, Melanie,Cui, Luchao,Mom, Sophal,Richard, Philippe,Saeys, Mark,Hierso, Jean-Cyrille
supporting information; experimental part, p. 3403 - 3414 (2012/02/02)
The present study highlights the potential of robust tridentate ferrocenylphosphanes with controlled conformation as catalytic auxiliaries in C-O bond formation reactions. Air-stable palladium triphosphane systems are efficient for selective heteroaryl ether synthesis by using as little as 0.2 mol% of catalyst. These findings represent an economically attractive and clean etherification of functionalized phenols, electron-rich, electron-poor and para-, meta- or ortho-substituted substrates, with heteroaryl chlorides, including pyridines, hydroxylated pyridine, pyrimidines and thiazole. The etherification tolerates very important functions in various positions, such as cyano, methoxy, amino, and fluoro groups, which is useful to synthesize bioactive molecules. DFT studies furthermore demonstrate that triphosphane ligands open up various new pathways for the C-O reductive elimination involving the third phosphane group. In particular, the rate for one of these new pathways is calculated to be about 1000 times faster than for reductive elimination from a complex with a similar ferrocenyl ligand, but without a phosphane group on the bottom Cp-ring. Coordination of the third phosphane group to the palladium(II) center is calculated to stabilize the transition state in this new pathway, thereby enhancing the reductive elimination rate. Copyright
Ortho-functionalization of 2-phenoxypyrimidines via palladium-catalyzed C-H bond activation
Gu, Shaojin,Chen, Chao,Chen, Wanzhi
supporting information; experimental part, p. 7203 - 7206 (2009/12/09)
(Chemical Equation Presented) The palladium-catalyzed direct acetoxylation and a3rylation of 2-aryloxypyrimidine has been described. The aromatic C-H bonds may be functionalized in moderate to excellent yields providing a facile method for the synthesis o
