340772-55-6Relevant academic research and scientific papers
Synthesis of sterically hindered biaryls by Zr-mediated Co-cyclotrimerization of alkynes
Dufkova, Lenka,Kotora, Martin,Cisarova, Ivana
, p. 2491 - 2499 (2005)
Treatment of zirconacyclopentadienes with ortho-substituted arylpropynoates in the presence of stoichiometric amounts of CuCl or NiBr 2(PPh3)2 represents a novel approach to the synthesis of biaryls, formed in good yields. The CuCl-mediated reaction proceeded through two reaction mechanisms, also affording Dewar benzenes together with the corresponding biaryls Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Oxidant- and additive-free simple synthesis of 1,1,2-triiodostyrenes by one-pot decaroboxylative iodination of propiolic acids
Ghosh, Subhankar,Ghosh, Rajat,Chattopadhyay, Shital K.
supporting information, (2020/09/15)
A metal- and oxidant-free facile synthesis of a range of 1,1,2-triiodostryrene derivatives has been developed which utilizes a simple decarboxylative triiodination of propiolic acids using molecular iodine and sodium acetate in a one-pot manner. Electron-
Cobalt(III)-Catalyzed Intermolecular Carboamination of Propiolates and Bicyclic Alkenes via Non-Annulative Redox-Neutral Coupling
Zhu, Yuelu,Chen, Feng,Zhao, Xinyang,Yan, Dingyuan,Yong, Wanxiong,Zhao, Jing
supporting information, p. 5884 - 5888 (2019/08/20)
A cobalt(III)-catalyzed, redox-neutral, intermolecular carboamination of propiolates and bicyclic alkenes was developed. This non-annulative coupling strategy features atom economy, high regioselectivity, good yields, and functional groups tolerance. Such a carboamination reaction was applied to modified phenols from the corresponding phenols under mild conditions.
Efficient Access to Chiral β-Borylated Carboxylic Esters via Rh-Catalyzed Hydrogenation
Liu, Gang,Li, Anqi,Qin, Xueyuan,Han, Zhengyu,Dong, Xiu-Qin,Zhang, Xumu
, p. 2844 - 2848 (2019/04/26)
Rh/bisphosphine?thiourea ligand (ZhaoPhos)-catalyzed asymmetric hydrogenation of (Z)-β-substituted-β-boryl-α,β-unsaturated esters was successfully developed, furnishing a variety of chiral β-borylated carboxylic esters with high yields and excellent enantioselectivities (up to 99% yield and >99% ee). The gram-scale asymmetric hydrogenation was performed efficiently in the presence of only 0.05 mol% (S/C=2 000) catalyst loading with full conversion, 99% yield and 99% ee. Moreover, the hydrogenation product was easily converted to other versatile synthetic intermediates, such as methyl (S)-3-hydroxy-3-phenylpropanoate and methyl (S)-3-(furan-2-yl)-3-phenylpropanoate. (Figure presented.).
Synthesis of Chiral β-Borylated Carboxylic Esters via Nickel-Catalyzed Asymmetric Hydrogenation
Han, Zhengyu,Liu, Gang,Zhang, Xianghe,Li, Anqi,Dong, Xiu-Qin,Zhang, Xumu
, p. 3923 - 3926 (2019/06/14)
The highly efficient Ni-catalyzed asymmetric hydrogenation of β-boronic ester substituted-α,β-unsaturated carboxylic esters was successfully developed using (S,S)-Ph-BPE as the ligand. A series of chiral β-borylated carboxylic esters were obtained with high yields (94%-99% yields) and excellent enantioselectivities (89%-99% ee). The gram-scale asymmetric hydrogenation with a low catalyst loading (0.25 mol %) and synthetic transformation of hydrogenation product demonstrated the great synthetic utility of this methodology.
Rhodium(III)-Catalyzed Redox-Neutral Cascade [3 + 2] Annulation of N-Phenoxyacetamides with Propiolates via C-H Functionalization/Isomerization/Lactonization
Pan, Jin-Long,Chen, Chao,Hao, Yu,Liu, Chang,Bai, He-Yuan,Ding, Jun,Zhang, Shu-Yu,Wang, Li-Ren,Xie, Peipei,Xia, Yuanzhi
supporting information, p. 7131 - 7136 (2018/12/14)
A Rh(III)-catalyzed cascade [3 + 2] annulation of N-phenoxyacetamides with propiolates under mild conditions using the internal oxidative O-N bond as the directing group has been achieved. This catalytic system provides a regio- and stereoselective access to benzofuran-2(3H)-ones bearing exocyclic enamino motifs with exclusive Z configuration selectivity, acceptable to good yields and good functional group compatibility. Mechanistic investigations by experimental and density functional theory studies suggest that a consecutive process of C-H functionalization/isomerization/lactonization is likely to be involved in the reaction.
Transition Metal-Free Trans Hydroboration of Alkynoic Acid Derivatives: Experimental and Theoretical Studies
Fritzemeier, Russell,Gates, Ashley,Guo, Xueying,Lin, Zhenyang,Santos, Webster L.
, p. 10436 - 10444 (2018/07/21)
We report a phosphine-catalyzed trans hydroboration of alkynoate esters and amides. The reaction proceeds under mild conditions with exclusive (E)-selectivity to afford (E)-β-boryl acrylates and (E)-β-boryl acrylamides in good to excellent yields. The reaction is tolerant of a variety of functional groups and allows efficient access to novel oxaboroles as well as a pargyline derivative (MAO inhibitor). Theoretical calculations suggest an internal hydride generates a phosphonium allenoxyborane followed by the formation of a key phosphonocyclobutene intermediate that collapses in a stereoselective, rate-limiting step.
Salt-Free Strategy for the Insertion of CO2 into C?H Bonds: Catalytic Hydroxymethylation of Alkynes
Wendling, Timo,Risto, Eugen,Krause, Thilo,Goo?en, Lukas J.
supporting information, p. 6019 - 6024 (2018/03/27)
A copper(I) catalyst enables the insertion of carbon dioxide into alkyne C?H bonds by using a suitable organic base with which hydrogenation of the resulting carboxylate salt with regeneration of the base becomes thermodynamically feasible. In the presence of catalytic copper(I) chloride/4,7-diphenyl-1,10-phenanthroline, polymer-bound triphenylphosphine, and 2,2,6,6-tetramethylpiperidine as the base, terminal alkynes undergo carboxylation at 15 bar CO2 and room temperature. After filtration, the ammonium alkynecarboxylate can be hydrogenated to the primary alcohol and water at a rhodium/molybdenum catalyst, regenerating the amine base. This demonstrates the feasibility of a salt-free overall process, in which carbon dioxide serves as a C1 building block in a C?H functionalization.
Pyranone, thiopyranone, and pyridone inhibitors of phosphatidylinositol 3-kinase related kinases. Structure-activity relationships for DNA-dependent protein kinase inhibition, and identification of the first potent and selective inhibitor of the ataxia telangiectasia mutated kinase
Hollick, Jonathan J.,Rigoreau, Laurent J. M.,Cano-Soumillac, Celine,Cockcroft, Xiaoling,Curtin, Nicola J.,Frigerio, Mark,Golding, Bernard T.,Guiard, Sophie,Hardcastle, Ian R.,Hickson, Ian,Hummersone, Marc G.,Menear, Keith A.,Martin, Niall M. B.,Matthews, Ian,Newell, David R.,Ord, Rachel,Richardson, Caroline J.,Smith, Graeme C. M.,Griffin, Roger J.
, p. 1958 - 1972 (2008/02/02)
Structure-activity relationships have been investigated for inhibition of DNA-dependent protein kinase (DNA-PK) and ATM kinase by a series of pyran-2-ones, pyran-4-ones, thiopyran-4-ones, and pyridin-4-ones. A wide range of IC50 values were observed for pyranones and thiopyranones substituted at the 6-position, with the 3- and 5-positions proving intolerant to substitution. Related pyran-2-ones, pyran-4-ones, and thiopyran-4-ones showed similar IC50 values against DNA-PK, whereas the pyridin-4-one system proved, in general, ineffective at inhibiting DNA-PK. Extended libraries exploring the 6-position of 2-morpholinopyran-4-ones and 2-morpholino- thiopyrano-4-ones identified the first highly potent and selective ATM inhibitor 2-morpholin-4-yl-6-thianthren-1-yl-pyran-4-one (151C; ATM; IC50 = 13 nM) and revealed constrained SARs for ATM inhibition compared with DNA-PK. One of the most potent DNA-PK inhibitors identified, 2-(4-methoxyphenyl)-6- (morpholin-4-yl)pyran-4-one (16; DNA-PK; IC50 = 220 nM) effectively sensitized HeLa cells to the topoisomerase II inhibitor etoposide in vitro.
