- Construction of α-Amino Azines via Thianthrenation-Enabled Photocatalyzed Hydroarylation of Azine-Substituted Enamides with Arenes
-
α-Amino azines are widely found in pharmaceuticals and ligands. Herein, we report a practical method for accessing this class of compounds via photocatalyzed hydroarylation of azine-substituted enamides with the in situ-generated aryl thianthrenium salts as the radical precursor. This reaction features a broad substrate scope, good functional group tolerance, and mild conditions and is suitable for the late-stage installation of α-amino azines in complex structures.
- Zhang, Yu-Lan,Wang, Gang-Hu,Wu, Yichen,Zhu, Chun-Yin,Wang, Peng
-
p. 8522 - 8526
(2021/11/13)
-
- "bulky-Yet-Flexible" α-Diimine Palladium-Catalyzed Reductive Heck Cross-Coupling: Highly Anti-Markovnikov-Selective Hydroarylation of Alkene in Air
-
To pursue a highly regioselective and efficient reductive Heck reaction, a series of moisture-and air-stable α-diimine palladium precatalysts were rationally designed, readily synthesized, and fully characterized. The relationship between the structures of the palladium complexes and the catalytic properties was investigated. It was revealed that the"bulky-yet-flexible"palladium complexes allowed highly anti-Markovnikov-selective hydroarylation of alkenes with (hetero)aryl bromides under aerobic conditions. Further synthetic application of the present protocol could provide rapid and straightforward access to functional and biologically active molecules.
- Yang, Xu-Wen,Li, Dong-Hui,Song, A-Xiang,Liu, Feng-Shou
-
p. 11750 - 11765
(2020/10/23)
-
- Iridium-Catalyzed C-Alkylation of Methyl Group on N-Heteroaromatic Compounds using Alcohols
-
In this study, we developed a catalytic system for the C-alkylation of a methyl group on N-heteroaromatic compounds, including pyridine, pyrimidine, pyrazine, quinoline, quinoxaline, and isoquinoline, using alcohols based on a hydrogen-borrowing process with [Cp*IrCl2]2 (Cp*: η5-pentamethylcyclopentadienyl) combined with potassium t-butoxide and 18-crown-6-ether as the catalyst precursor.
- Onoda, Mitsuki,Fujita, Ken-Ichi
-
supporting information
p. 7295 - 7299
(2020/10/02)
-
- Ni-catalyzed Reductive Deaminative Arylation at sp3 Carbon Centers
-
A Ni-catalyzed reductive deaminative arylation at unactivated sp3 carbon centers is described. This operationally simple and user-friendly protocol exhibits excellent chemoselectivity profile and broad substrate scope, thus complementing existing metal-catalyzed cross-coupling reactions to forge sp3 C-C linkages. These virtues have been assessed in the context of late-stage functionalization, hence providing a strategic advantage to reliably generate structure diversity with amine-containing drugs.
- Martin-Montero, Raul,Yatham, Veera Reddy,Yin, Hongfei,Davies, Jacob,Martin, Ruben
-
p. 2947 - 2951
(2019/04/30)
-
- Catalytic alkylation of methyl-N-heteroaromatics with alcohols
-
(Chemical Equation Presented) A novel catalytic C-C coupling reaction in which N-heteroaromatic-substituted methyl groups are efficiently alkylated using primary alcohols is introduced. The synthesis protocol is based on iridium catalysts and most likely relies on the borrowing hydrogen or hydrogen autotransfer mechanism. A variety of substrate combinations can readily be employed in this reaction, including pyrimidines, pyrazines, pyridazines, and even fairly activated 2- and 4-picolines. Copyright
- Blank, Benoit,Kempe, Rhett
-
supporting information; experimental part
p. 924 - 925
(2010/03/31)
-
- Redox-niediation of electron-electron spin-spin exchange interactions, |J|, in paramagnetic trinuclear molybdenum complexes: An example of a 'J switch'
-
A series of trinuclear molybdenum nitrosyl complexes has been prepared using the dinucleating ligands 4-(4-hydroxyphenyl)pyridine (HL1), 1-(4-pyridyl)-2-(4-hydroxyphenyl)-ethene (HL2) and -ethane (HL3), and the trinucleating ligands 3,5-bis(4-hydroxyphenyl)pyridine (H2L4) and 2,6-bis(4-ethenylpyridyl)-4-hydroxytoluene (HL5). These complexes are of the type [Mo{OC6H4EpyMoCl}2] (Mo = Mo(NO)TpMe,Me, TpMe,Me = tris(3,5-dimethylpyrazolyl)borate; E = nothing, CH=CH and CH2CH2; py = C5H4N or C5H3N; from HL1, HL2 and HL3), [{ClMo(OC6H4)}2pyMoCl] (from H2L4), and [ClMo{OC6H3Me[CH=CHpyMoCl]2}] (from HL5). The species [Mo{OC6H4EpyMoCl}2] contains one 16 valence electron (ve) ([Mo{OC6H4-}2]) and two 17 ve centres ([(-py)MoCl]), [{ClMo(OC6H4)}2pyMoCl] has two 16 ([ClMo{OC6H4-}]) and one 17 ([(-py)MoCl]) ve centres and [ClMo{OC6H3Me[CH=CHpyMoCl]2}] one 16 and two 17 ve centres. Reduction of these species by cobaltocene in tetrahydrofuran/dichloromethane mixtures affords complexes having three 17 ve centres with one unpaired electron per metal centre. The interaction between these impaired electrons in solution is determined by the relationship between |J|, the electron spin-spin exchange interaction, and AMo, the molybdenum hyperfine coupling constant, which was detected by EPR spectroscopy. In [Mo{OC6H4EpyMoCl}2], the interaction was dependent on ligand conformation, |J| ≈ AMo when E = nothing, |J| ? AMo when E = CH=CH and |J| ? AMo when E = CH2CH2. Reduction of [Mo{OC6H4EpyMoCl}2] to [Mo{OC6H4EpyMoCl}2]- resulted in exchange between all three spins irrespective of ligand conformation, and the EPR spectra of [{ClMo(OC6H4)}2pyMoCl]2- and [ClMo{OC6H3Me[CH=CHpyMoCl]2}]- were similar to that of [Mo{OC6H4EpyMoCl}2]-. Oxidation reconstitutes the original EPR spectra of [Mo{OC6H4EpyMoCl}2], [{ClMo(OC6H4)}2pyMoCl] and [ClMo{OC6H3Me-[CH=CHpyMoCl]2}]. This behaviour is consistent with full three centre interaction being 'switched on' when the 17:16:17 or 16:17:16 ve systems are reduced to a 17:17:17 ve system, and 'switched off' on reoxidation. The Royal Society of Chemistry 2000.
- Psillakis, Elefteria,Shonfield, Peter K.A.,Jouaiti, Abdel-Aziz,Maher, John P.,McCleverty, Jon A.,Ward, Michael D.
-
p. 241 - 249
(2007/10/03)
-
- Electrochemical Adamantylation of Styrylpyridines
-
The reaction between electrochemically generated anion radicals of the 4-(4-styryl)-pyridines 1-6 and 1-bromoadamantane gives, in solvents of low proton availability as N,N-dimethylformamide via an electron transfer in solution and formation of 1-adamantyl-radicals, monoadamantylated pyrid-4-yl-phenylethanes.The major product results from an anion radical/radical-coupling in the 2(β)-next the 1(α)-position.A competing pathway of the electrohydroadamantylation is the hydrogeneration of the -CH=CH-double bond, whose importance increases with the water content of the solvent.Based on cyclic-voltammetric evidence and product distribution, the mechanism of the reductive coupling of 1-6 in the presence of 1-bromoadamantane is discussed in terms of indirect electrolysis.
- Hess, U.,Huhn, D.
-
p. 301 - 308
(2007/10/02)
-