Close the ring to break the cycle: tandem quinolone-alkyne-cyclisation gives access to tricyclic pyrrolo[1,2-a]quinolin-5-ones with potent anti-protozoal activity
Ferric Chloride Hexahydrate-Catalyzed Highly Regio- and Stereoselective Conjugate Addition Reaction of 2,3-Allenoates with Grignard Reagents: An Efficient Synthesis of β,γ-Alkenoates
作者:Guobi Chai、Zhan Lu、Chunling Fu、Shengming Ma
DOI:10.1002/adsc.200900091
日期:2009.8
Ferricchloride hexahydrate was shown to be an efficient catalyst for the conjugate addition of 2,3-allenoates with alkyl-, aryl-, or vinyl-Grignard reagents to synthesize polysubstituted β,γ-unsaturated alkenoates with high regio- and stereoselectivity. The in situ formed magnesium dienolate may readily react with different electrophilic reagents under different reaction conditions with or without
CuCl-catalyzed stereoselective conjugate addition of Grignard reagents to 2,3-allenoates
作者:Jian He、Zhan Lu、Guobi Chai、Chunling Fu、Shengming Ma
DOI:10.1016/j.tet.2012.01.027
日期:2012.3
CuCl was found to be an efficient catalyst for the conjugateaddition of 2,3-allenoates with Grignardreagents to synthesize poly-substituted β,γ-unsaturated alkenoates with high stereoselectivity in good to excellent yields. Primary, secondary, and tertiary alkyl, vinyl or phenyl Grignardreagents may all be used.
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
Manganese(I)‐Catalyzed Regio‐ and Stereoselective 1,2‐Diheteroarylation of Allenes: Combination of C−H Activation and Smiles Rearrangement
作者:Shi‐Yong Chen、Xiang‐Lei Han、Jia‐Qiang Wu、Qingjiang Li、Yunyun Chen、Honggen Wang
DOI:10.1002/anie.201704952
日期:2017.8.7
functional molecules. A MnI-catalyzed 1,2-diheteroarylation of allenes via a C−H activation/Smiles rearrangement cascade is presented. The reaction occurred under additive-free or even solvent-free conditions, which allowed the creation of two C−C and one C−N bonds in a single operation. A series of structurally diverse bicyclic or tricyclic compounds bearing an exocyclic double bond were constructed in