676-00-6Relevant academic research and scientific papers
Gold N-Heterocyclic Carbene Catalysts for the Hydrofluorination of Alkynes Using Hydrofluoric Acid: Reaction Scope, Mechanistic Studies and the Tracking of Elusive Intermediates
Bédard, Sandrine,Cavallo, Luigi,Falivene, Laura,Gauthier, Rapha?l,Nolan, Steven P.,Paquin, Jean-Fran?ois,Saab, Marina,Tzouras, Nikolaos V.,Van Hecke, Kristof,Zhang, Ziyun
supporting information, (2021/12/09)
An efficient and chemoselective methodology deploying gold-N-heterocyclic carbene (NHC) complexes as catalysts in the hydrofluorination of terminal alkynes using aqueous HF has been developed. Mechanistic studies shed light on an in situ generated catalyst, formed by the reaction of Br?nsted basic gold pre-catalysts with HF in water, which exhibits the highest reactivity and chemoselectivity. The catalytic system has a wide alkyl substituted-substrate scope, and stoichiometric as well as catalytic reactions with tailor-designed gold pre-catalysts enable the identification of various gold species involved along the catalytic cycle. Computational studies aid in understanding the chemoselectivity observed through examination of key mechanistic steps for phosphine- and NHC-coordinated gold species bearing the triflate counterion and the elusive key complex bearing a bifluoride counterion.
METHOD FOR PRODUCING CARBONYL COMPOUND
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Paragraph 0163-0164, (2021/01/26)
A method for producing a carbonyl compound represented by formula (1): wherein R1 is hydrogen or an organic group; R2 is hydrogen or an organic group; and R3 is hydrogen or an organic group; or two or three of R1, R2, and R3 may be linked to form a ring that may have at least one substituent, the method comprising step A of oxidizing an olefin compound represented by formula (2): wherein symbols are as defined above, by an oxidizing agent in the presence of (a) a non-alcohol organic solvent, (b) water, (c) a metal catalyst, and (d) an additive represented by the formula: MXn, wherein M is an element belonging to any one of Group 1, Group 2, Group 13, Group 14, and Group 15 in the periodic table, or NR4, wherein R is hydrogen or a C1-10 organic group; X is halogen; and n is a number of 1 to 5.
Olefination via Cu-Mediated Dehydroacylation of Unstrained Ketones
Dong, Guangbin,Xu, Yan,Zhou, Xukai
supporting information, p. 20042 - 20048 (2021/12/03)
The dehydroacylation of ketones to olefins is realized under mild conditions, which exhibits a unique reaction pathway involving aromatization-driven C-C cleavage to remove the acyl moiety, followed by Cu-mediated oxidative elimination to form an alkene between the α and β carbons. The newly adopted N′-methylpicolinohydrazonamide (MPHA) reagent is key to enable efficient cleavage of ketone C-C bonds at room temperature. Diverse alkyl- and aryl-substituted olefins, dienes, and special alkenes are generated with broad functional group tolerance. Strategic applications of this method are also demonstrated.
SULFONIC ACID, CARBOXYLIC ACID, AND SALTS THEREOF
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Paragraph 0355-0361, (2020/02/10)
A sulfonic acid or carboxylic acid containing a carbonyl group, or a salt thereof represented by the following formula: [in-line-formulae]R1—C(═O)—(CR22)—(OR3)p—(CR42)q-L-A[/in-line-formulae] wherein R1, R2, R3, R4, n, p, q, A and L are as defined herein.
Tsuji-Wacker Oxidation of Terminal Olefins using a Palladium-Carbon Nanotube Nanohybrid
Donck, Simon,Gravel, Edmond,Shah, Nimesh,Jawale, Dhanaji V.,Doris, Eric,Namboothiri, Irishi N. N.
, p. 2318 - 2322 (2015/08/11)
Palladium nanoparticles supported on carbon nanotubes were used in the Tsuji-Wacker oxidation. The palladium-based nanohybrid was found to be very active in combination with cuprous chloride for the selective oxidation of terminal olefins into methyl ketones. The co-catalytic system operates under very mild and sustainable conditions (room temperature, atmospheric pressure, low catalyst loading), as opposed to previously reported catalysts, and can be recycled without any loss in activity. Give it a whack: Palladium nanoparticles supported on carbon nanotubes are used in combination with cuprous chloride for the selective Tsuji-Wacker oxidation of terminal olefins into methyl ketones. The co-catalytic system operates under very mild and sustainable conditions and can be recycled without any loss in activity.
Stereospecific synthesis of 23-hydroxyundecylprodiginines and analogues and conversion to antimalarial premarineosins via a Rieske oxygenase catalyzed bicyclization
Kancharla, Papireddy,Lu, Wanli,Salem, Shaimaa M.,Kelly, Jane Xu,Reynolds, Kevin A.
, p. 11674 - 11689 (2015/02/05)
Facile and highly efficient synthetic routes for the synthesis of (S)- and (R)-23-hydroxyundecylprodiginines ((23S)-2, and (23R)-2), 23-ketoundecylprodiginine (3), and deuterium-labeled 23-hydroxyundecylprodiginine ([23-d]-2) have been developed. We demon
The synthesis of β-keto lactones via cyclization of β-keto ester dianions or the cyclization of Meldrum's acid derivatives
Lermer, Leonard,Neeland, Edward G.,Ounsworth, James P.,Sims, Russell J.,Tischler, Samuel A.,Weiler, Larry
, p. 1427 - 1445 (2007/10/02)
Two new methods to synthesize macrocyclic β-keto lactones have been developed.The first involves the synthesis of ω-halo-β-keto esters and an intramolecular alkylation of the dianions to these compounds.The reaction is complicated by elimination in the small and medium ring systems and by difficulties in purifying the final products.However, it is possible to obtain modest yields of the desired β-keto lactones.This procedure was used to synthesize the 25- and 27-membered ring β-hydroxy lactones that are the constituents of termite defense compounds.The second method involves the thermolysis of acylated Meldrum's acid derivatives, which leads directly to β-keto lactones.This process gives modest yields of macrocyclic systems and good yield of the unsubstituted 3-oxopentan-5-olide (25) .The 14-membered macrocyclic β-keto lactone 9j has a complex 1H NMR spectrum, which has been interpreted in terms of multiple conformations.The temperature dependence of the NMR spectrum of 9j is consistent with entropic, rather than enthalpic, control of the equilibrium.Quasiharmonic entropy calculations are consistent with this model.
Indirect Electrooxidation of Alkohols and Aldehydes by Using a Double Mediatory System Consisting of RuO4/RuO2 and Cl+/Cl- Redoxes in an Aqueous-Organic Two-Phase System
Torii, Sigeru,Inokuchi, Tsutomu,Sugiura, Toyoyuki
, p. 155 - 161 (2007/10/02)
A double mediatory system consisting of RuO4/RuO2 and Cl+/Cl- redox couples has been developed for the indirect electrooxidation of alcohols and aldehydes.The reaction proceeds in the following manner: (1) oxidation of the substrate with ruthenium tetraoxide (RuO4) in the organic layer, (2) regeneration of ruthenium tetraoxide from ruthenium dioxide (RuO2) with active chlorine species (Cl2 or +), and (3) oxidation of chloride ion to + on the anode in the aqueous layer.The range of applicability of the present procedure is discussed by oxidations of (1)secondary alcohols to ketones, (2) primary alcohols and aldehydes to carboxylic acid, (3) 1,n-diols to lactones and keto acids, and (4) carbohydrate derivatives.
