Close the ring to break the cycle: tandem quinolone-alkyne-cyclisation gives access to tricyclic pyrrolo[1,2-<i>a</i>]quinolin-5-ones with potent anti-protozoal activity
作者:Dávid Szamosvári、Kayla Sylvester、Philipp Schmid、Kuan-Yi Lu、Emily R. Derbyshire、Thomas Böttcher
DOI:10.1039/c9cc01689a
日期:——
We describe a tandem reaction leading to tricyclic pyrrolo[1,2-a]quinolin-5-ones with unique selectivity against the liver stage of the malaria parasite.
Asymmetric Olefin Isomerization of Butenolides via Proton Transfer Catalysis by an Organic Molecule
作者:Yongwei Wu、Ravi P. Singh、Li Deng
DOI:10.1021/ja205674x
日期:2011.8.17
general olefin isomerization was realized via biomimetic protontransfer catalysis with a new chiral organic catalyst. A broad range of mono- and disubstituted β,γ-unsaturated butenolides were transformed into the corresponding chiral α,β-unsaturated butenolides in high enantioselectivity and yield in the presence of as low as 0.5 mol % catalyst. Mechanistic studies have revealed the protonation as the
The Renaissance of an Old Problem: Highly Regioselective Carboxylation of 2-Alkynyl Bromides with Carbon Dioxide
作者:Bukeyan Miao、Gen Li、Shengming Ma
DOI:10.1002/chem.201503494
日期:2015.11.23
A steric effect‐controlled, zinc‐mediated carboxylation of different 2‐alkynyl bromides under an atmosphericpressure of CO2 has been developed by careful tuning of different reaction parameters, including the metal, solvent, temperature, and additive. 2‐Substituted 2,3‐allenoic acids were afforded from primary 2‐alkynyl bromides, whereas the carboxylation of secondary 2‐alkynyl bromides yielded 3‐alkynoic
One-Step Asymmetric Construction of 1,4-Stereocenters via Tandem Mannich-Isomerization Reactions Mediated by a Dual-Functional Betaine Catalyst
作者:Yu Deng、Xiaohuo Shi、Guangfa Shi、Xingyu Lu、Jisheng Luo、Li Deng
DOI:10.1021/jacsau.2c00465
日期:2022.12.26
Mannich-isomerization reaction that allows the direct construction of 1,4-stereocenters in a highly stereoselective manner. This asymmetric transformation demonstrated the potential of a tandem nucleophilic addition-isomerization reaction as a broadly useful strategy for the efficient construction of 1,4-stereocenters. Notably, this tandem reaction was mediated by a single chiral betaine as a dual-functional
Switchable multipath cascade cyclization to synthesize bicyclic lactams and succinimides <i>via</i> chemodivergent reaction
作者:Yimei Song、Chaofei Wu、Jinhai Zhang、Wenhai Zhang、Xin Qin、Yixiao Yang、Guowei Kang、Jun Jiang、Hongxin Liu
DOI:10.1039/d2cc06841a
日期:——
Herein, a novel switchable multipath cascade cyclizationvia chemodivergent reaction between readily available ketoamides and deconjugated butenolides was developed to efficiently synthesize γ-lactone fused γ-lactams and succinimide fused hemiketals. The Aldol/aza-Michael reaction and Aldol/imidation/hemiketalization reaction were enabled by catalytic amounts of two bases, namely tetramethyl guanidine