The highly stereoselective allylicalkylation of Morita–Baylis–Hillman carbonates with β-ketoesters catalysed by β-ICD is described. The corresponding products containing two adjacent quaternary and tertiary carbon centers were obtained in good yields with high diastereoselectivity (up to 10 : 1 dr) and enantioselectivity (up to 95% ee).
Lewis base-catalyzed cyanation of Morita-Baylis-Hillman carbonates. Synthesis of allylamine derivatives
作者:Hai Ma、Feng Sui、Qing-He Zhao、Ning Zhang、Yi Sun、Jing Xian、Meng-Jiao Jiao、Yu-ling Liu、Zhi-Min Wang
DOI:10.1016/j.tetlet.2017.07.038
日期:2017.8
DABCO-catalyzed cyanation of MBH carbonates via 1,3-proton shift transfer is reported. The adducts of cyanation are converted in one step to allylic amines derivatives. The salient features of this reaction include readily available starting materials, mild conditions, broad substrate scope, high efficiency and valuable further applications. The process of the 1,3-proton shift transfer was conducted
Asymmetric Allylic Monofluoromethylation and Methylation of Morita-Baylis-Hillman Carbonates with FBSM and BSM by Cooperative Cinchona Alkaloid/FeCl2 Catalysis
yields with high ee values (see scheme, (DHQD)2AQN=hydroquinidine(anthraquinone‐1,4‐diyl) diether). The cooperativecatalysis of bis(cinchona alkaloid) and Lewis acid, particularly FeCl2, was effective for these transformations and gave the monofluoromethylation products with over 90 % ee and methylation products with up to 97 % ee.
The highly enantioselective asymmetric allylic alkylation of Morita–Baylis–Hillmancarbonates with bis(phenylsulfonyl)methane is presented. The reaction is simply catalyzed by cinchonaalkaloid derivatives affording the final alkylated products in good yields and enantioselectivities.
Construction of Adjacent Quaternary and Tertiary Stereocentersvia an Organocatalytic Allylic Alkylation of Morita–Baylis–Hillman Carbonates
作者:Dirk Jan V. C. van Steenis、Tommaso Marcelli、Martin Lutz、Anthony L. Spek、Jan H. van Maarseveen、Henk Hiemstra
DOI:10.1002/adsc.200600467
日期:2007.2.5
Racemic Baylis–Hillman carbonates can be converted in densely functionalized products by reaction with cyano esters in the presence of a catalytic amount of a modified Cinchona alkaloid in high enantioselectivities and fair diastereoselectivities. A rational for the observed stereoselectivity is presented.