13139-86-1Relevant academic research and scientific papers
Biaryls made easy: PEPPSI and the Kumada-Tamao-Corriu reaction
Organ, Michael G.,Abdel-Hadi, Mirvat,Avola, Stephanie,Hadei, Niloufar,Nasielski, Joanna,O'Brien, Christopher J.,Valente, Cory
, p. 150 - 157 (2007)
An easily employed, highly versatile Kumada-Tamao-Corriu (KTC) protocol utilizing the PEPPSI (Pyridine, Enhanced, Precatalyst, Preparation, Stabilization and Initiation) precatalysts 1 and 2 is detailed. The ease-of-use of these catalysts and the synthesis of a wide range of hindered biaryls, large coupling partners and drug-like heterocycles, in high yield, makes the PEPPSI-KTC protocol very attractive. The high reactivity of the PEPPSI system allowed a tetra-ortho substituted heterocycle, 11 to be synthesized at room temperature for the first time using any protocol. The PEPPSI protocols also tolerated the Boc protecting group and phenols required no protection in modified conditions. A relatively large scale (10g) reaction was also performed with no loss in performance. Furthermore, PEPPSI IPr, 1, was compared to previously reported highly active phosphine ligands 42, 43, and 44 and was shown to result in significantly better yields under identical conditions. Finally, we demonstrated that the PEPPSI catalyst system is very adept at performing sequential KTC coupling reactions, analogous to multicomponent reactions, which allow complex polyaryl and polyheteroaryl architectures to be produced in one single operation.
Processes for the Preparation of Zuclomiphene and Intermediates Thereof
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Paragraph 0140-0141, (2021/05/21)
The present invention provides processes for the preparation of zuclomiphene, as well as intermediates useful in the preparation thereof. In particular, processes are provided for the carbometallation of diphenylacetylene with a compound of Formula (3) to afford either zuclomiphene or an intermediate which is converted to zuclomiphene.
Room-Temperature Palladium(II)-Catalyzed Direct 2-Arylation of Indoles with Tetraarylstannanes
Liu, Yuxia,Wang, Chao,Huang, Linjuan,Xue, Dong
supporting information, p. 1613 - 1618 (2020/09/15)
A palladium(II)-catalyzed direct 2-arylation of indoles by tetraarylstannanes with oxygen (balloon) as the oxidant at room temperature has been developed. Various tetraarylstannanes can be employed as aryl sources for 2-arylation of indoles in up to 89% yield, providing a practical and efficient catalytic protocol for accessing 2-arylindoles.
Strain-Promoted 1,3-Dithiolium-4-olates–Alkyne Cycloaddition
Kumar, Ramar Arun,Pattanayak, Manas R.,Yen-Pon, Expédite,Eliyan, Jijy,Porte, Karine,Bernard, Sabrina,Riomet, Margaux,Thuéry, Pierre,Audisio, Davide,Taran, Frédéric
supporting information, p. 14544 - 14548 (2019/09/17)
Reported here is the reactivity of mesoionic 1,3-dithiolium-4-olates towards strained alkynes, leading to thiophene cycloaddition products. In the process, the potential of these dipoles towards orthogonal reaction with azides, allowing efficient double ligation reactions, was discovered. A versatile process to access benzo[c]thiophenes, in an unprecedented divergent fashion, was developed and provides a new entry to unconventional polyaromatic thiophenes.
Chromium(II)-Catalyzed Diastereoselective and Chemoselective Csp2-Csp3 Cross-Couplings Using Organomagnesium Reagents
Li, Jie,Ren, Qianyi,Cheng, Xinyi,Karaghiosoff, Konstantin,Knochel, Paul
supporting information, p. 18127 - 18135 (2019/11/19)
A simple protocol for performing chromium-catalyzed highly diastereoselective alkylations of arylmagnesium halides with cyclohexyl iodides at ambient temperature has been developed. Furthermore, this ligand-free CrCl2 enables efficient electrophilic alkenylations of primary, secondary, and tetiary alkylmagnesium halides with readily available alkenyl acetates. Moreover, this chemoselective C-C coupling reaction with stereodefined alkenyl acetates proceeds in a stereoretentive fashion. A wide range of functional groups on alkyl iodides and alkenyl acetates are well tolerated, thus furnishing functionalized Csp2-Csp3 coupling products in good yields and high diastereoselectivity. Detailed mechanistic studies suggest that the in situ generated low-valent chromium(I) species might be the active catalyst for these Csp2-Csp3 cross-couplings.
Nickel-Catalyzed Cross-Coupling of Functionalized Organo manganese Reagents with Aryl and Heteroaryl Halides Promoted by 4-Fluorostyrene
Benischke, Andreas D.,Desaintjean, Alexandre,Juli, Thomas,Cahiez, Gérard,Knochel, Paul
supporting information, p. 5396 - 5412 (2017/12/14)
A catalytic system consisting of Ni(acac) 2 (5 mol%) and 4-fluorostyrene (20 mol%) allows a convenient cross-coupling of functionalized organomanganese reagents with a variety of aryl and heteroaryl halides leading to polyfunctionalized diaryl- and arylheteroarylmethane derivatives.
A Short Access to Symmetrically α,α-Disubstituted α-Amino Acids from Acyl Cyanohydrins
Boukattaya, Fatma,Caillé, Julien,Ammar, Houcine,Rouzier, Florian,Boeda, Fabien,Pearson-Long, Morwenna S. M.,Bertus, Philippe
, p. 906 - 916 (2016/03/12)
A straightforward synthesis of symmetrically α,α-disubstituted α-amino acids is presented. The key step of this process relies on the efficient double addition of Grignard reagents to acyl cyanohydrins to provide N-acyl amino alcohols selectively in good yields. The chemoselectivity of the reaction was modulated by the nature of the acyl moiety. Eleven amino acids were prepared, including the particularly simple divinylglycine, which is not easily accessible by using conventional methods.
Nickel-Catalyzed Asymmetric Kumada Cross-Coupling of Symmetric Cyclic Sulfates
Eno, Meredith S.,Lu, Alexander,Morken, James P.
supporting information, p. 7824 - 7827 (2016/07/11)
Nickel-catalyzed enantioselective cross-couplings between symmetric cyclic sulfates and aromatic Grignard reagents are described. These reactions are effective with a broad range of substituted cyclic sulfates and deliver products with asymmetric tertiary carbon centers. Mechanistic experiments point to a stereoinvertive SN2-like oxidative addition of a nickel complex to the electrophilic substrate.
Facile Hydrogenolysis of C(sp3)–C(sp3) σ Bonds
Fillion, Eric,Beaton, Eric,Nguyen, Yen,Wilsily, Ashraf,Bondarenko, Ganna,Jacq, Jér?me
supporting information, p. 3422 - 3434 (2016/11/13)
The modification of benzylic quaternary, tertiary, and secondary carbon centers through palladium-catalyzed hydrogenolysis of C(sp3)–C(sp3) σ bonds is presented. When benzyl Meldrum's acid derivatives bearing quaternary benzylic centers are treated under mild hydrogenolysis conditions – palladium on carbon and atmospheric pressure of hydrogen – aromatics substituted with tertiary benzylic centers and Meldrum's acid are obtained with good to excellent yield. Analogously, substrates containing tertiary or secondary benzylic centers yield aromatics substituted with secondary benzylic centers or toluene derivatives, respectively. Furthermore, this strategy is used for the high yielding synthesis of diarylmethanes. The scope of the reductive dealkylation reaction is explored and the limitations with respect to steric and electronic factors are determined. A mechanistic analysis of the reaction is described that consisted of deuterium labelling experiments and hydrogenolysis of enantioenriched derivatives. The investigation shows that the C(sp3)–C(sp3) σ bond-cleaving events occur through a hybrid SN1/SN2 mechanism, in which the palladium center displaces a carbon-based leaving group, namely Meldrum's acid, with inversion of configuration, followed by reductive elimination of palladium to furnish a C?H bond. (Figure presented.).
Bismuth-catalyzed synthesis of polycyclic aromatic hydrocarbons (PAHs) with a phenanthrene backbone via cyclization and aromatization of 2-(2-arylphenyl)vinyl ethers
Murai, Masahito,Hosokawa, Naoki,Roy, David,Takai, Kazuhiko
supporting information, p. 4134 - 4137 (2014/09/30)
The reaction of 2-(2-arylphenyl)vinyl ethers in the presence of a catalytic amount of bismuth(III) triflate gave substituted phenanthrenes in excellent yields under mild reaction conditions. The reaction was also applied to the construction of other polycyclic aromatic hydrocarbons (PAHs), such as chrysene, helicene, and pyrene having a phenanthrene backbone, via regioselective cyclization. This method has the advantages of easy availability of the cyclization precursors, operational simplicity, and high reaction efficiency.
