3825-81-8Relevant academic research and scientific papers
Ni-Catalyzed Reductive Allylation of α-Chloroboronates to Access Homoallylic Boronates
Lou, Yixian,Qiu, Jian,Yang, Kai,Zhang, Feng,Wang, Chenglan,Song, Qiuling
supporting information, p. 4564 - 4569 (2021/06/28)
The transition-metal-catalyzed allylation reaction is an efficient strategy for the construction of new carbon-carbon bonds alongside allyl or homoallylic functionalization. Herein we describe a Ni-catalyzed reductive allylation of α-chloroboronates to efficiently render the corresponding homoallylic boronates, which could be readily converted into valuable homoallylic alcohols or amines or 1,4-diboronates. This reaction features a broad substrate scope with good functional group compatibility that is complementary to the existing methods for the preparation of homoallylic boronates.
HETEROAROMATIC COMPOUNDS AS VANIN INHIBITORS
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Paragraph 0282; 0380-0387, (2020/03/23)
The present invention encompasses compounds of the formula I which are suitable for the treatment of diseases related to Vanin, and processes for making these compounds, pharmaceutical preparations containing these compounds, and their methods of use.
Aqueous ZnCl2 Complex Catalyzed Prins Reaction of Silyl Glyoxylates: Access to Functionalized Tertiary α-Silyl Alcohols
Han, Man-Yi,Pan, Hong,Li, Pinhua,Wang, Lei
, p. 5825 - 5837 (2020/05/22)
An efficient Prins reaction of silyl glyoxylates in the presence of an aqueous ZnCl2 complex as a catalyst was developed, providing functionalized tertiary α-silyl alcohols in high yields under mild conditions. A preliminary investigation indicated that the aqueous ZnCl2 complex acted as a dual functional catalyst of Br?nsted and Lewis acid to activate the carbonyl groups of silyl glyoxylates via a dual-activation model.
Iridium-Catalyzed Isomerization of N-Sulfonyl Aziridines to Allyl Amines
Cabré, Albert,Sciortino, Giuseppe,Ujaque, Gregori,Verdaguer, Xavier,Lledós, Agustí,Riera, Antoni
supporting information, p. 5747 - 5751 (2018/09/21)
The Crabtree's reagent catalyzes the isomerization of N-sulfonyl 2,2-disubstituted aziridines to allyl amines. The selectivity of allyl amine vs imine is very high (up to 99/1). The unprecedented isomerization takes place in mild conditions without activation of the catalyst by hydrogen. The mechanism has been studied computationally by DFT calculations; instead of the usual hydrogenation of COD, the catalytic species is formed by a loss of the pyridine ligand. Approaching of aziridine to this unsaturated species leads to a carbocation intermediate through a low energy barrier. A metal-mediated tautomerization involving sequentially γ-H elimination and N-H reductive elimination affords selectively the allyl amine. The readiness of the CγH bond to participate in the H elimination step accounts for the selectivity toward the allyl amine product.
A Copper Catalyst with a Cinchona-Alkaloid-Based Sulfonamide Ligand for Asymmetric Radical Oxytrifluoromethylation of Alkenyl Oximes
Li, Xi-Tao,Gu, Qiang-Shuai,Dong, Xiao-Yang,Meng, Xiang,Liu, Xin-Yuan
supporting information, p. 7668 - 7672 (2018/05/30)
A copper-catalyzed asymmetric radical oxytrifluoromethylation of alkenyl oxime and Togni's reagent has been successfully developed, thereby providing straightforward access to CF3-containing isoxazolines bearing α-tertiary stereocenters with excellent yield and enantioselectivity. The key to success is the rational design of cinchona-alkaloid-based sulfonamides as neutral/anionic hybrid ligands to effectively control the stereochemistry in copper-catalyzed reactions involving free alkyl radical species. The utility of this method is illustrated by efficient transformation of the products into useful chiral CF3-containing 1,3-aminoalcohols.
Regiocontrolled synthesis of α-sulfonylmethyl o-nitrostyrenes via ZnI2-mediated sulfonylation and AgNO2/Pd(PPh3)4-promoted o-nitration
Chang, Meng-Yang,Chen, Han-Yu,Wang, Heui-Sin
, p. 10601 - 10610 (2018/05/31)
We report herein the AgNO2/Pd(PPh3)4-promoted regiocontrolled o-nitration of α-sulfonylmethylstyrenes in MeNO2 with good yields. The o-nitration process provides a series of sulfonyl o-nitrostyrenes. Substituted α-sulfonylmethylstyrenes were synthesized from ZnI2-mediated sulfonylation of substituted α-methylstyrenes and sodium sulfinates (RSO2Na) in MeCN with good to excellent yields. The structures of the key products were confirmed by X-ray crystallography. A plausible mechanism has been proposed herein.
Chelation versus Non-Chelation Control in the Stereoselective Alkenyl sp2 C?H Bond Functionalization Reaction
Liang, Qiu-Ju,Yang, Chao,Meng, Fei-Fan,Jiang, Bing,Xu, Yun-He,Loh, Teck-Peng
supporting information, p. 5091 - 5095 (2017/04/24)
A hydroxy group chelation-assisted stereospecific oxidative cross-coupling reaction between alkenes was developed under mild reaction conditions. In the presence of palladium catalyst, the alkenes tethered with hydroxy functionality can couple efficiently with electron-deficient alkenes to form the corresponding multi-substituted olefin products. The hydroxy group on the substrate could play dual roles in reaction, acting as the directing group for alkenyl C?H bond activation and controlling the stereoselectivity of the products.
Towards nitrile-substituted cyclopropanes-a slow-release protocol for safe and scalable applications of diazo acetonitrile
Hock, Katharina J.,Spitzner, Robin,Koenigs, Rene M.
supporting information, p. 2118 - 2122 (2017/07/24)
Diazo acetonitrile has long been neglected despite its high value in organic synthesis due to a high risk of explosions. Herein, we report our efforts towards the transient and safe generation of this diazo compound, its applications in iron catalyzed cyclopropanation and cyclopropenation reactions and the gram-scale synthesis of cyclopropyl nitriles.
Highly enantioselective hydrogenation of β,β-disubstituted nitroalkenes
Li, Shengkun,Huang, Kexuan,Cao, Bonan,Zhang, Jiwen,Wu, Wenjun,Zhang, Xumu
supporting information; experimental part, p. 8573 - 8576 (2012/09/10)
Building the building blocks: A highly enantioselective hydrogenation of ?-aryl-?-alkyl disubstituted nitroalkenes 1 has been developed. This method results in enantiomerically pure nitroalkanes 2, which are versatile precursors for chemical synthesis.
Carbocation-forming reactions in ionic liquids
Creary, Xavier,Willis, Elizabeth D.,Gagnon, Madeleine
, p. 18114 - 18120 (2007/10/03)
A number of trifluoroacetates, mesylates, and triflates have been studied in ionic liquids. Several lines of evidence indicate that all of these substrates react via ionization to give carbocationic intermediates. For example, cumyl trifluoroacetates give mainly the elimination products, but the Hammett ρ+ value of -3.74 is consistent with a carbocationic process. The analogous exo-2-phenyl-endo-3-deutero-endo-bicyclo-[2.2.1]hept-2-yl trifluoroacetate gives an elimination where loss of the exo-hydrogen occurs from a cationic intermediate. 1-Adamantyl mesylate and 2-adamantyl triflate react to give simple substitution products derived from capture of 1- and 2-adamantyl carbocations by the residual water in the ionic liquid. The triflate derivative of pivaloin, trans-2-phenylcyclopropylcarbinyl mesylate, 2,2-dimethoxycyclobutyl triflate, the mesylate derivative of diethyl (phenylhydroxymethyl)-thiophosphonate, and Z-1-phenyl-5-trimethylsilyl-3-penten- 1-yl trifluoroacetate all give products derived carbocation rearrangements (kΔ processes), anti-7-Norbornenyl mesylate gives products with complete retention of configuration, indicative of involvement of the delocalized 7-norbornenyl cation. 1,6-Methano[10]annulen-11-yl triflate reacts in [BMIM][NTf2] to give 1,6-methano[10]annulen-11-ol, along with naphthalene, an oxidized product derived from loss of trifluoromethanesulfinate ion. Analogous loss of CF3SO2- can be seen in reaction of PhCH(CF3)OTf. Ionic liquids are therefore viable solvents for formation of carbocationic intermediates via kc and k Δ processes.
