2109-22-0Relevant articles and documents
Rh2(II)-Catalyzed intermolecular N-Aryl aziridination of olefins using nonactivated N atom precursors
Deng, Tianning,Mazumdar, Wrickban,Yoshinaga, Yuki,Patel, Pooja B.,Malo, Dana,Malo, Tala,Wink, Donald J.,Driver, Tom G.
, p. 19149 - 19159 (2021/11/23)
The development of the first intermolecular Rh2(II)-catalyzed aziridination of olefins using anilines as nonactivated N atom precursors and an iodine(III) reagent as the stoichiometric oxidant is reported. This reaction requires the transfer of an N-aryl nitrene fragment from the iminoiodinane intermediate to a Rh2(II) carboxylate catalyst; in the absence of a catalyst only diaryldiazene formation was observed. This N-aryl aziridination is general and can be successfully realized by using as little as 1 equiv of the olefin. Di-, tri-, and tetrasubstituted cyclic or acylic olefins can be employed as substrates, and a range of aniline and heteroarylamine N atom precursors are tolerated. The Rh2(II)-catalyzed N atom transfer to the olefin is stereospecific as well as chemo- and diastereoselective to produce the N-aryl aziridine as the only amination product. Because the chemistry of nonactivated N-aryl aziridines is underexplored, the reactivity of N-aryl aziridines was explored toward a range of nucleophiles to stereoselectively access privileged 1,2-stereodiads unavailable from epoxides, and removal of the N-2,4-dinitrophenyl group was demonstrated to show that functionalized primary amines can be constructed.
Ligand-Controlled Direct Hydroformylation of Trisubstituted Olefins
Shin, Taeil,Kim, Hyungsoo,Kim, Sungmin,Lee, Ansoo,Seo, Min-Seob,Choi, Jonghoon,Kim, Hyungjun,Kim, Hyunwoo
supporting information, p. 5789 - 5792 (2019/06/24)
The direct hydroformylation of trisubstituted olefins has been achieved with a combination of a Rh(I) catalyst and a π-acceptor phosphorus (briphos) ligand. A sterically bulky briphos ligand with a large cone angle that forms a 1:1 complex with Rh(I) is found to be reactive for the hydroformylation of trisubstituted olefins. The aldehyde products were obtained with high diastereoselectivity (>99:1) and regioselectivity (49%-81%).
Asymmetric α-Allylation of Aldehydes with Alkynes by Integrating Chiral Hydridopalladium and Enamine Catalysis
Su, Yong-Liang,Li, Lu-Lu,Zhou, Xiao-Le,Dai, Zhen-Yao,Wang, Pu-Sheng,Gong, Liu-Zhu
supporting information, p. 2403 - 2406 (2018/04/27)
A palladium-catalyzed asymmetric α-allylation of aldehydes with alkynes has been established by integrating the catalysis of enamine and chiral hydridopalladium complex that is reversibly formed from the oxidative addition of Pd(0) to chiral phosphoric acid. The ternary catalyst system, consisting of an achiral palladium complex, a primary amine, and a chiral phosphoric acid allows the reaction to tolerate a wide scope of α,α-disubstituted aldehydes and alkynes, affording the corresponding allylation products in high yields and with excellent levels of enantioselectivity.
NRF2 REGULATORS
-
Page/Page column 347, (2017/01/02)
Provided are aryl analogs，pharmaceutical compositions containing them and their use as NRF2 regulators.
Dynamic kinetic asymmetric amination of alcohols: From a mixture of four isomers to diastereo- and enantiopure α-branched amines
Rong, Zi-Qiang,Zhang, Yao,Chua, Raymond Hong Bing,Pan, Hui-Jie,Zhao, Yu
supporting information, p. 4944 - 4947 (2015/05/05)
The first dynamic kinetic asymmetric amination of alcohols via borrowing hydrogen methodology is presented. Under the cooperative catalysis by an iridium complex and a chiral phosphoric acid, α-branched alcohols that exist as a mixture of four isomers undergo racemization by two orthogonal mechanisms and are converted to diastereo- and enantiopure amines bearing adjacent stereocenters. The preparation of diastereo- and enantiopure 1,2-amino alcohols is also realized using this catalytic system.
An air-stable cationic iridium hydride as a highly active and general catalyst for the isomerization of terminal epoxides
Humbert, Nicolas,Vyas, Devendra J.,Besnard, Céline,Mazet, Clément
supporting information, p. 10592 - 10595 (2014/10/15)
We describe the use of an air-stable iridium hydride catalyst for the isomerization of terminal epoxides into aldehydes with perfect regioselectivity. The system operates at low loadings of catalyst (0.5 mol%), is highly practical, scalable, and tolerates functional groups that would not be compatible with Lewis acids typically used in stoichiometric amounts. Evidence for a rare hydride mechanism are provided. This journal is the Partner Organisations 2014.
Chiral monodentate phosphine ligands for the enantioselective α- And γ-arylation of aldehydes
Franzoni, Ivan,Guénée, Laure,Mazet, Clément
supporting information, p. 4181 - 4190 (2014/06/09)
The synthesis of chiral variants of monodentate trialkyl and dialkylbiaryl phosphine ligands elaborated on the binepine scaffold is described. Their application in the Pd-catalyzed intramolecular asymmetric α-arylation of aldehydes and the intermolecular asymmetric γ-arylation of α,β-unsaturated aldehydes provides a mean of validating the design of these ligands. For the first reaction, excellent reactivities have been obtained while only modest enantioselectivities were measured. Aside from enantioselectivity, the second reaction offers additional challenges associated with intramolecularity and regioselectivity. With the formal chiral trialkyl monodentate phosphine ligands, good yield, high olefin stereocontrol, and perfect γ-selectivity were obtained while the enantioselectivity remained in the low but promising range.
METHOD FOR HYDROFORMYLATION OF UNSATURATED COMPOUNDS
-
Paragraph 0087, (2014/02/16)
The invention relates to a method for hydroformylation of unsaturated compounds such as olefins and alkynes using mixtures of synthesis gas (CO/H2), in which either the unsaturated compounds and a catalyst are heated to a reaction temperature of 60 to 200° C. and the synthesis gas is then added, or the unsaturated compounds and the catalyst are brought into contact with pure CO at normal temperature in a preformation step, then are heated to reaction temperature and on reaching the reaction temperature the CO is replaced by the synthesis gas. The pressure is 1 to 200 bar and the CO:H2 ratio in the synthesis gas is in the range from 1:1 to 50:1. The iridium catalyst used comprises a phosphorus-containing ligand in the iridium:ligand ratio in the range from 1:1 to 1:100. With high catalyst activities and low catalyst use, very high turnover frequencies are achieved.
Ligand-metal cooperating PC(sp3)P pincer complexes as catalysts in olefin hydroformylation
Musa, Sanaa,Filippov, Oleg A.,Belkova, Natalia V.,Shubina, Elena S.,Silantyev, Gleb A.,Ackermann, Lutz,Gelman, Dmitri
supporting information, p. 16906 - 16909 (2014/01/06)
Ligand-metal cooperation: A new ligand-metal cooperating catalyst for the hydroformylation of olefins is described (see scheme). The mechanism of the H2 activation and C-H bond formation of the catalyst involves an intramolecular cooperation between the structurally remote functionality and the metal center and proceeds without change of the oxidation state of the metal.
Isomerization of terminal epoxides by a [Pd-H] catalyst: A combined experimental and theoretical mechanistic study
Vyas, Devendra J.,Larionov, Evgeny,Besnard, Celine,Guenee, Laure,Mazet, Clement
supporting information, p. 6177 - 6183 (2013/06/04)
An unusual palladium hydride complex has been shown to be a competent catalyst in the isomerization of a variety of terminal and internal epoxides. The reaction displayed broad scope and synthetic utility. Experimental and theoretical evidence are provided for an unprecedented hydride mechanism characterized by two distinct enantio-determining steps. These results hold promise for the development of an enantioselective variant of the reaction.
