69491-44-7Relevant academic research and scientific papers
Cobalt-Catalyzed Preparation of N -Heterocyclic Organozinc Reagents from the Corresponding Heteroaryl Chlorides
Godineau, Edouard,Graβl, Simon,Knochel, Paul,Kremsmair, Alexander,Seifert, Christoph J. B.
, p. 4068 - 4074 (2021/08/10)
Various substituted and unsubstituted N -heteroaryl chlorides have been converted into their corresponding organozinc species using zinc dust in the presence of zinc pivalate and 10% CoCl 2in benzonitrile at 25 °C. The resulting heteroarylzinc
Cyclometallated 2-Phenylpyrimidine Derived Platinum Complexes: Synthesis and Photophysical Properties
Fecková, Michaela,Kahlal, Samia,Roisnel, Thierry,Saillard, Jean-Yves,Boixel, Julien,Hruzd, Mariia,le Poul, Pascal,Gauthier, Sébastien,Robin-le Guen, Fran?oise,Bure?, Filip,Achelle, Sylvain
, p. 1592 - 1600 (2021/04/28)
A series of five platinum (II) complexes based on 2-phenylpyrimidine ligands have been designed. Pyridine and chloride were used as auxiliary ligands. These complexes exhibit a slightly distorted square-planar geometry. The nature and position of substitu
Direct C-H photoarylation of diazines using aryldiazonium salts and visible-light
Silva, Rodrigo C.,Villela, Lucas F.,Brocksom, Timothy J.,De Oliveira, Kleber T.
, p. 31115 - 31122 (2020/09/23)
In this study, direct C-H photoarylation of pyrazine with aryldiazonium salts under visible-light irradiation (blue-LEDs) is described, and additional examples including photoarylations of pyrimidine and pyridazine are also covered. The corresponding aryl-diazines were prepared in yields up to 84% only by mixing and irradiating the reaction with no need for an additional photocatalyst. We demonstrate the efficacy of this protocol by the scope with electron-donor, -neutral, and -withdrawing groups attached at the ortho, meta, and para positions of the aryldiazonium salts; the results are better than those reported for ruthenium-complex mediated photoarylations. Additionally, we demonstrate the robustness of this methodology with a 5 mmol scaled-up experiment. Mechanistic studies were carried out giving support to the proposal of a photocatalyzed approach by an electron donor-acceptor (EDA) complex, also highlighting the crucial role that solvents play in the formation of the EDA complex. This journal is
Heterocyclic Allylsulfones as Latent Heteroaryl Nucleophiles in Palladium-Catalyzed Cross-Coupling Reactions
Markovic, Tim,Murray, Philip R.D.,Rocke, Benjamin N.,Shavnya, Andre,Blakemore, David C.,Willis, Michael C.
supporting information, p. 15916 - 15923 (2018/11/23)
Heterocyclic sulfinates are effective reagents in palladium-catalyzed coupling reactions with aryl and heteroaryl halides, often providing high yields of the targeted biaryl. However, the preparation and purification of complex heterocylic sulfinates can be problematic. In addition, sulfinate functionality is not tolerant of the majority of synthetic transformations, making these reagents unsuitable for multistep elaboration. Herein, we show that heterocyclic allylsulfones can function as latent sulfinate reagents and, when treated with a Pd(0) catalyst and an aryl halide, undergo deallylation, followed by efficient desulfinylative cross-coupling. A broad range of allyl heteroarylsulfones are conveniently prepared, using several complementary routes, and are shown to be effective coupling partners with a variety of aryl and heteroaryl halides. We demonstrate that the allylsulfone functional group can tolerate a range of standard synthetic transformations, including orthogonal C- and N-coupling reactions, allowing multistep elaboration. The allylsulfones are successfully coupled with a variety of medicinally relevant substrates, demonstrating their applicability in demanding cross-coupling transformations. In addition, pharmaceutical agents crizotinib and etoricoxib were prepared using allyl heteroaryl sulfone coupling partners, further demonstrating the utility of these new reagents.
Catalyst Selection Facilitates the Use of Heterocyclic Sulfinates as General Nucleophilic Coupling Partners in Palladium-Catalyzed Coupling Reactions
Markovic, Tim,Rocke, Benjamin N.,Blakemore, David C.,Mascitti, Vincent,Willis, Michael C.
supporting information, p. 6033 - 6035 (2017/11/27)
A range of 5- and 6-membered heterocycle-derived sulfinates are shown to be effective nucleophilic coupling partners with aryl chlorides and bromides using Pd(0) catalysis. The use of optimal reaction conditions, specifically incorporating a P(t-Bu)2Me-derived Pd catalyst, allowed reactions to be performed at moderate temperatures and enabled the inclusion of a variety of sensitive functional groups. Challenging heterocyclic sulfinates, including pyrazine, pyridazine, pyrimidine, pyrazole, and imidazole, were all shown to perform well.
α-Halo carbonyls enable: Meta selective primary, secondary and tertiary C-H alkylations by ruthenium catalysis
Paterson, Andrew J.,Heron, Callum J.,McMullin, Claire L.,Mahon, Mary F.,Press, Neil J.,Frost, Christopher G.
supporting information, p. 5993 - 6000 (2017/07/25)
A catalytic meta selective C-H alkylation of arenes is described using a wide range of α-halo carbonyls as coupling partners. Previously unreported primary alkylations with high meta selectivity have been enabled by this methodology whereas using straight chain alkyl halides affords ortho substituted products. Mechanistic analysis reveals an activation pathway whereby cyclometalation with a ruthenium(ii) complex activates the substrate molecule and is responsible for the meta selectivity observed. A distinct second activation of the coupling partner allows site selective reaction between both components.
Ruthenium-Catalyzed meta-Selective C?H Mono- and Difluoromethylation of Arenes through ortho-Metalation Strategy
Li, Zhong-Yuan,Li, Liang,Li, Qi-Li,Jing, Kun,Xu, Hui,Wang, Guan-Wu
supporting information, p. 3285 - 3290 (2017/03/16)
The first example for the ruthenium-catalyzed ligand-directed meta-selective C?H mono- and difluoromethylation is developed, affording a variety of new meta-mono- and difluoromethylated 2-phenylpyridines, 2-phenylpyrimidines, and 1-phenylpyrazoles in moderate-to-good yields. This new transformation exhibits broad substrate scope, good functional group tolerance, and high efficiency, and offers a practical approach to synthesize mono- and difluoromethylated arenes. Mechanistic studies indicate that a reaction pathway involving palladium-initiated radical species is involved in the catalytic cycle. The new dual catalytic system consisting of compatible ruthenium(II) and palladium(0) complexes enables the key processes of C?H activation and mono-/difluoromethyl-radical formation to occur and achieves the meta-selective functionalization efficiently. In addition, the present protocol can also be extended to non-fluoromethylation.
Copper acetate-DMSO promoted methylthiolation of arenes and heteroarenes
Sharma, Poonam,Rohilla, Sandeep,Jain, Nidhi
, p. 4116 - 4122 (2015/05/05)
An unprecedented copper acetate-DMSO promoted methylthiolation of arenes and heteroarenes in the presence of air has been developed. The reaction is highly regioselective under the directing group influence of pyridine and pyrimidine functional units and gives the thiomethylated product in moderate to high yields.
Ruthenium-catalyzed double-fold C-H tertiary alkoxycarbonylation of arenes using di-tert-butyl dicarbonate
Hong, Xiaohu,Wang, Hao,Liu, Bingxin,Xu, Bin
supporting information, p. 14129 - 14132 (2014/12/11)
An efficient ruthenium-catalyzed double-fold C-H alkoxycarbonylation of arenes was developed using di-tert-butyl dicarbonate as the tertiary esterification reagent, which leads to a direct route to valuable 2,6-dicarboxylated products. This journal is
Efficient and benign one-pot conversion of n-tosyl-1,4,5,6- tetrahydropyrimidines to pyrimidines via tandem β-elimination and aromatization
Trieu, Tien Ha,Dong, Jing,Shi, Xiao-Xin,Lu, Xia,Zhang, Qiang
, p. 3141 - 3152 (2014/01/06)
An efficient, mild, benign, and practical method for one-pot conversion of N-tosyl-1,4,5,6-tetrahydropyrimidines into pyrimidines is discussed in detail. In this method, N-tosyl-1,4,5,6-tetrahydropyrimidines are first prepared via N-tosylation of tetrahyd
