Enantioselective desymmetrization of prochiral 1,3-dinitropropanes via organocatalytic allylic alkylation
作者:Soumya Jyoti Singha Roy、Santanu Mukherjee
DOI:10.1039/c3cc47645f
日期:——
An enantioselective desymmetrization of prochiral 1,3-dinitropropanes has been developed which proceeds via enantiogroup differentiating organocatalyticallylicalkylation. Densely functionalized products with two vicinal stereocenters were obtained generally with good to excellent diastereoselectivity (up to >20 : 1 dr) and superb enantioselectivity (up to >99 : 1 er).
Water mediated trapping of active methylene intermediates generated by IBX-induced oxidation of Baylis–Hillman adducts with nucleophiles
作者:Jia-Neng Tan、Haoquan Li、Yanlong Gu
DOI:10.1039/c0gc00274g
日期:——
Baylis–Hillman adduct with IBX. The generated product, a methyleneintermediate, could be trapped in situ by many nucleophiles in water, such as styrenes, β-dicarbonyl compounds, benzamide and less reactive indoles. This strategy offers an alternative way to methylenylation of β-dicarbonyl compounds with formaldehyde for the formation of a methyleneintermediate, thus allows the use of some nucleophiles that
Electron-Donor–Acceptor Complex-Enabled Flow Methodology for the Hydrotrifluoromethylation of Unsaturated β-Keto Esters
作者:Gabriel M. F. Batista、Pedro P. de Castro、Hélio F. Dos Santos、Kleber T. de Oliveira、Giovanni W. Amarante
DOI:10.1021/acs.orglett.0c03187
日期:2020.11.6
(EDA) complex-enabled flow photochemical hydrotrifluoromethylation of unsaturated β-keto esters is described. The developed protocol has an easy experimental procedure and does not require the use of transition-metal-based photocatalysts, allowing the isolation of 14 new compounds in up to 86% yield. Control experiments and computational studies revealed that the reaction proceeds through a Michael-type
Catalytic Enantioselective Vinylogous Allylic Alkylation of Coumarins
作者:Satavisha Kayal、Santanu Mukherjee
DOI:10.1021/acs.orglett.7b02421
日期:2017.9.15
An unprecedented, organocatalytic enantioselective vinylogous γ-allylic alkylation of 4-methylcoumarins has been developed. Using allylic carbonates as the allyl source, this reaction is catalyzed by Lewis basic dimeric Cinchona alkaloid (QD)2PHAL and proceeds exclusively in a γ- and branched-selective manner to produce densely functionalized coumarin derivatives generally in good yields with good
Ligand-Dependent Regiodivergent Enantioselective Allylic Alkylations of α-Trifluoromethylated Ketones
作者:Yi Zhu、Yifan Ni、Chenxi Lu、Xiaochen Wang、Yi Wang、Xiao-Song Xue、Yi Pan
DOI:10.1021/acs.orglett.1c00329
日期:2021.4.2
catalytic and enantioselective addition of α-CF3 enolates allows for expeditious access to functionalized chiral building blocks with CF3-containing stereogenicity. The computational studies reveal that the choice of ligand in a designed palladium-complex system regulates the regioselectivity and stereoselectivity of the asymmetric allylic alkyation of α-CF3 ketones and Morita–Baylis–Hillmanadducts.