13124-61-3Relevant academic research and scientific papers
Divergent Synthesis of Highly Substituted Pyridines and Benzenes from Dienals, Alkynes, and Sulfonyl Azides
Luo, Han,Li, You,Du, Luan,Xin, Xiaolan,Wang, Tao,Han, Jingpeng,Tian, Yi,Li, Baosheng
supporting information, p. 7883 - 7887 (2021/10/20)
Divergent synthesis is extremely important for the highly efficient preparation of structurally diverse target molecules. Herein, we describe a multicomponent cascade reaction, which allows access to highly substituted pyridines and benzenes by combining four individual steps in a one-pot manner from the same set of readily available starting materials. The azepine intermediates were first used as the precursors for 6π-electrocyclization to construct highly substituted pyridines and benzenes in a tunable manner.
6-Arylphenanthridines from Aryl o-Biaryl Ketones with 1,1,1,3,3,3-Hexamethyldisilazane and Molecular Iodine
Kobayashi, Eiji,Kishi, Atsushi,Togo, Hideo
, p. 7335 - 7347 (2019/11/22)
Warming treatment of aryl o-biaryl ketones with 1,1,1,3,3,3-hexamethyldisilazane in the presence of Sc(OTf)3 in toluene, followed by the reaction with molecular iodine and K2CO3 in a mixture of THF and methanol at 60 °C gave the corresponding 6-arylphenanthridines in good to moderate yields. The present reaction is a one-pot method for the preparation of 6-arylphenanthridines from aryl o-biaryl ketones through the cyclization of imino-nitrogen-centered radicals that were generated from N-iodo aryl o-biaryl ketimines formed from the reaction of aryl biaryl ketimines with molecular iodine.
Stereoselective synthesis of folded luminogens with arene-arene stacking interactions and aggregation-enhanced emission
Zhao, Zujin,He, Bairong,Nie, Han,Chen, Bin,Lu, Ping,Qin, Anjun,Tang, Ben Zhong
supporting information, p. 1131 - 1133 (2014/01/17)
Tetraphenylethene derivatives with a folded Z-conformation and aggregation-enhanced emission characteristics are synthesized from 2-arylbenzophenones. The intramolecular rotation of the folded luminogens is partially suppressed, resulting in improved emission efficiencies in solutions.
Nickel-catalyzed cross-coupling of aryl fluorides and organozinc reagents
Zhu, Feng,Wang, Zhong-Xia
, p. 4285 - 4292 (2014/06/09)
Ni(PCy3)2Cl2 was demonstrated to effectively catalyze cross-coupling of aryl fluorides and organozinc reagents. Both electron-poor and -rich aryl fluorides can react effectively with nucleophiles including aryl-, methyl-, and benzylzinc chlorides. A wide range of substituents and functional groups are tolerated. In the presence of a directing group, PhC(O), the reaction is selective for cleavage of the C-F bond ortho to the carbonyl substituent in a difluoroarene.
Nickel-catalyzed cross-coupling of non-activated or functionalized aryl halides with aryl grignard reagents
Xie, Lan-Gui,Wang, Zhong-Xia
supporting information; experimental part, p. 10332 - 10336 (2010/10/21)
Figure Presented New nickel complexes can efficiently catalyze cross-coupling of unactivated and deactivated aryl chlorides and fluorides with aryl Grignard reagents. The reaction can tolerate functional groups in aryl chlorides with or without the aid of additives, depending on the substrates (see scheme).
New cyclopentadienyl, indenyl or fluorenyl substituted phosphine compounds and their use in catalytic reactions
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Page/Page column 48; 50; 52, (2008/06/13)
The invention is directed to a phosphine compound represented by general formula (1) wherein R' and R" independently are selected from alkyl, cycloalkyl and 2-furyl radicals, or R' and R" are joined together to form with the phosphorous atom a carbon-phosphorous monocycle comprising at least 3 carbon atoms or a carbon-phosphorous bicycle; the alkyl radicals, cycloalkyl radicals, and carbon-phosphorous monocycle being unsubstituted or substituted by at least one radical selected from the group of alkyl, cycloalkyl, aryl, alkoxy, and aryloxy radicals; Cps is a partially substituted or completely substituted cyclopentadien-1-yl group, including substitutions resulting in a fused ring system, and wherein a substitution at the 1-position of the cyclopentadien-1-yl group is mandatory when the cyclopentadien-1-yl group is not part of a fused ring system or is part of an indenyl group. Also claimed is the use of these phosphines as ligands in catalytic reactions and the preparation of these phosphines.
Catalytic enantioselective reformatsky reaction with ortho-substituted diarylketones
Fernandez-Ibanez, M. Angeles,Macia, Beatriz,Minnaard, Adriaan J.,Feringa, Ben L.
supporting information; experimental part, p. 4041 - 4044 (2009/05/27)
(Chemical Equation Presented) The catalytic enantioselective Reformatsky reaction with ortho-substituted diarylketones with good enantioselectivities and moderate to good yields is reported. A readily available BINOL derivative is used as a chiral catalyst, and the reactions are performed with ethyl iodoacetate as a nucleophile and Me2Zn as the zinc source. The presence of air was found to be crucial to achieve an effective C-C bond formation pointing to a radical mechanism.
9-Fluorenylphosphines for the Pd-catalyzed Sonogashira, Suzuki, and Buchwald-Hartwig coupling reactions in organic solvents and water
Fleckenstein, Christoph A.,Plenio, Herbert
, p. 2701 - 2716 (2008/03/14)
The lithiation/alkylation of fluorene leads to various 9-alkyl-fluorenes (alkyl = Me. Et, /Pr, -Pr. -C18H25) in > 95% yields, for which lithiation and reaction with R2PCl (R = Cy, iPr, tBu) generates 9-alkyl, 9-PR2fluorenes which constitute electron-rich and bulky phosphine ligands. The in-situ-formed palladium-phosphinc complexes ([Na2PdCl4], phosphonium salt, base, substrates) were tested in the Sonogashira. Suzuki, and Buchwald-Hartwig reactions of aryl chlorides and aryl bromides in organic solvents. The Sonogashira coupling of aryl chlorides at 100-120°C leads to >90% yields with 1 mol % of Pd catalyst. The Suzuki coupling of aryl chlorides typically requires 0.05 mol % of Pd catalyst at 100°C in dioxane for quantitative product formation. To carry out "green" cross-coupling reactions in water, 9-ethylfluorenyldicyclohexylphosphine was reacted in sulphuric acid to generate the respective 2-sulfonated phosphonium salt. The Suzuki coupling of activated aryl chlorides by using this water-soluble catalyst requires only 0.01 mol% of Pd catalyst, while a wide range of aryl chlorides can be quantitatively converted into the respective coupling products by using 0.1-0.5 mol % of catalyst in pure water at 100°C. Difficult substrate combinations, such as naphthylboronic acid or 3-pyridylboronic acid and aryl chlorides are coupled at 100°C by using 0.1-0.5 mol % of catalyst in pure water to obtain the respective N-heterocycles in quantitative yields. The copper-free aqueous Sonogashira coupling of aryl bromides generates the respective tolane derivatives in > 95 % yield.
Efficient cross-coupling of aryl chlorides with arylzinc reagents catalyzed by amido pincer complexes of nickel
Wang, Li,Wang, Zhong-Xia
, p. 4335 - 4338 (2008/03/11)
The nickel-catalyzed Negishi cross-coupling reaction of aryl chlorides with arylzinc compounds was investigated. The nickel complexes with the amido pincer type of ligands exhibited high catalytic activity and good functional group tolerance.
