4442-82-4Relevant academic research and scientific papers
Asymmetric transfer hydrogenation of unsaturated ketones; factors influencing 1,4- vs 1,2- regio- and enantioselectivity, and alkene vs alkyne directing effects
Hall, Thomas H.,Adams, Hannah,Vyas, Vijyesh K.,Michael Chu,Wills, Martin
, (2020/12/07)
A detailed study has been completed on the asymmetric transfer hydrogenation (ATH) of a series of enones using Ru(II) catalysts. Electron-rich rings adjacent to the C[dbnd]O group reduce the level of C[dbnd]O reduction compared to C[dbnd]C. The ATH reaction can readily discriminate between double and triple bonds adjacent to ketones, reducing the double bond but leaving a triple bond intact in the major product.
Regioselective Vinylation of Remote Unactivated C(sp3)?H Bonds: Access to Complex Fluoroalkylated Alkenes
Wu, Shuo,Wu, Xinxin,Wang, Dongping,Zhu, Chen
supporting information, p. 1499 - 1503 (2019/01/04)
Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C?H bonds is of great synthetic value. Despite advances in radical-mediated functionalization of C(sp3)?H bonds by a hydrogen-atom transfer process, the site-selective vinylation of remote C(sp3)?H bonds still remains underexplored. Reported herein is a new protocol for the regioselective vinylation of unactivated C(sp3)?H bonds. The remote C(sp3)?H activation is promoted by a C-centered radical instead of the commonly used N and O radicals. The reaction possesses high product diversity and synthetic efficiency, furnishing a plethora of synthetically valuable E alkenes bearing tri-/di-/mono-fluoromethyl and perfluoroalkyl groups.
Nickel-Catalyzed Stereoselective Arylboration of Unactivated Alkenes
Logan, Kaitlyn M.,Sardini, Stephen R.,White, Sean D.,Brown, M. Kevin
supporting information, p. 159 - 162 (2018/01/17)
A Ni-catalyzed method for arylboration is disclosed. The method allows for highly stereoselective arylboration of unactivated alkenes. The reactions utilize a simple Ni-catalyst and work with a broad range of alkenes and aryl bromides. The products represent useful intermediates for chemical synthesis due to the versatility of the C-B bond. Preliminary mechanistic details of the method are also disclosed.
Multicomponent Oxyalkylation of Styrenes Enabled by Hydrogen-Bond-Assisted Photoinduced Electron Transfer
Tlahuext-Aca, Adrian,Garza-Sanchez, R. Aleyda,Glorius, Frank
supporting information, p. 3708 - 3711 (2017/03/21)
Herein, we disclose a strategy for the activation of N-(acyloxy)phthalimides towards photoinduced electron transfer through hydrogen bonding. This activation mode enables efficient access to C(sp3)-centered radicals upon decarboxylation from bench-stable and readily available substrates. Moreover, we demonstrate that the formed alkyl radicals can be successfully employed in a novel redox-neutral method for constructing sp3?sp3 bonds across styrene moieties that gives straightforward access to complex alcohol and ether scaffolds.
Clean borrowing hydrogen methodology using hydrotalcite supported copper catalyst
Dixit, Manish,Mishra, Manish,Joshi, Pradyuman A.,Shah, Dinesh O.
, p. 80 - 83 (2013/05/09)
The catalytic activity of Mg-Al hydrotalcite supported copper catalyst was investigated for clean CC and CN bond forming reactions using alcohols as alkylating agent via borrowing hydrogen methodology. The catalyst showed excellent conversion of ketone and amine substrates (71-99%) to alkylated products with high selectivity in alkylation reactions.
4-HYDROXY-BENZOPYRAN-2-ONES AND 4-HYDROXY-CYCLOALKYL[B]PYRAN-2-ONES USEFUL TO TREAT RETROVIRAL INFECTIONS
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, (2008/06/13)
The present invention relates to compounds of formula I which are 4-hydroxy-benzopyran-2-ones and 4-hydroxy-cycloalkyl[b]pyran-2-ones useful for inhibiting a retrovirus in a mammalian cell infected with said retrovirus. STR1 Wherein R 10 and R 20 taken together are: STR2
Reductive Transformations, 19. Electron-Transfer-Induced Dimerization of β-Alkylstyrenes and the Structures of Resulting 1,4-Dilithiobutanes
Schade, Peter,Schaefer, Thomas,Muellen, Klaus,Bender, Dietmar,Knoll, Konrad,Bronstert, Klaus
, p. 2833 - 2842 (2007/10/02)
Upon reaction with lithium β-alkylstyrenes undergo dimerization of the resulting radical anions with the formation of 2,3-dialkyl-1,4-dilithio-1,4-diphenyl butanes 1-8.The structure and dynamic behavior of these dilithium organyls are investigated by cryoscopic measurements and 1H-, 13C-, and 6Li-NMR spectroscopy at different temperatures.The butane chain adopts a cisoid conformation; the two benzyl subunits chelate one lithium cation while the other is solvent-separated from the hydrocarbon frame.Depending on the size of the alkyl substitutents and the reaction temperature, the dimerization of the radical anions with the formation of two stereogenic centers can proceed diastereoselectively.Key Words: Lithium organyls/ 1,4-Dilithiobutanes, conformation of ,ion paris of, aggregation of
