Highly Enantioselective Synthesis of γ-Hydroxy-α,β-acetylenic Esters Catalyzed by a β-Sulfonamide Alcohol
作者:Li Lin、Xianxing Jiang、Weixia Liu、Li Qiu、Zhaoqing Xu、Jiangke Xu、Albert S. C. Chan、Rui Wang
DOI:10.1021/ol070692x
日期:2007.6.1
concerns the asymmetric addition of methyl propiolate to aldehydes with 1,2-dimethoxyethane (DME) as additive and beta-sulfonamide alcohol titanium complex as a catalyst. The reactions proceeded under mild conditions and gave the highly functionalized chiral propargylic alcohols with high ee values and good yields. Differences between three types of ligands have also been discussed.
Highly Enantioselective Synthesis of γ-Hydroxy-α,β-acetylenic Esters by Asymmetric Alkyne Addition to Aldehydes
作者:Ge Gao、Qin Wang、Xiao-Qi Yu、Ru-Gang Xie、Lin Pu
DOI:10.1002/anie.200500469
日期:2006.1
Robust eco-friendly protocol for the preparation of γ-hydroxy-α,β-acetylenic esters by sequential one-pot elimination–addition of 2-bromoacrylates to aldehydes promoted by LTMP in 2-MeTHF
作者:Vittorio Pace、Laura Castoldi、Andrés R. Alcántara、Wolfgang Holzer
DOI:10.1039/c2gc35305a
日期:——
An efficient and widely applicable preparation of γ-hydroxy-α,β-acetylenicesters is described by means of a one-pot dehydrobromination of a 2-bromoacrylate ester with LTMP followed by the electrophilic addition of the transient propiolate to different aldehydes in the eco-friendly solvent 2-MeTHF.
Mg(OMe)<sub>2</sub> promoted allylic isomerization of γ-hydroxy-α,β-alkenoic esters to synthesize γ-ketone esters
作者:Luhao Lai、A-Ni Li、Jiawei Zhou、Yarong Guo、Li Lin、Wei Chen、Rui Wang
DOI:10.1039/c7ob00131b
日期:——
This work concerns the Mg(OMe)2 promoted allylic isomerization of γ-hydroxy-α,β-alkenoic esters with TMEDA as an additive. The isomerization proceeded under mild conditions and afforded γ-keto esters in high yield (up to 96%) within 2 h. Both (Z)- and (E)-γ-hydroxy-α,β-alkenoic esters were tolerated under the reaction conditions. This transformation involves the in situ formation of a dienolate intermediate