Enantioselective Synthesis of Trifluoromethyl α,β-Unsaturated δ-Lactones via Vinylogous Aldol-Lactonization Cascade
作者:Simone Crotti、Nicola Di Iorio、Andrea Mazzanti、Paolo Righi、Giorgio Bencivenni
DOI:10.1021/acs.joc.8b01672
日期:2018.10.19
by a bifunctional tertiary amine, provides an efficient application of the vinylogous reactivity of alkylidene oxindoles for the preparation of enantioenriched trifluoromethylated α,β-unsaturated δ-lactones.
The Vinylogous Michael Addition of 3‐Alkylidene‐2‐oxindoles to β,γ‐Unsaturated α‐Keto Esters by Bifunctional Cinchona Alkaloids
作者:Manish K. Jaiswal、Rajesh Kumar、Sanjay Singh、Shailija Jain、Kumar Vanka、Ravi P. Singh
DOI:10.1002/ejoc.202000835
日期:2020.9.22
A highly enantioselective vinylogous Michaeladdition of 3‐alkylidene‐2‐oxindoles with β,γ‐unsaturated α‐keto esters using a bifunctional tertiary‐amine thiourea catalyst is demonstrated. The challenging Michael reaction with the β,γ‐unsaturated α‐keto esters has been accomplished due to the synchronized H‐bond guided dual activation of vinylogous nucleophile and electrophile by catalyst. The reaction
证明了使用双官能叔胺硫脲催化剂,对3-亚烷基-2-氧吲哚和β,γ-不饱和α-酮酯的高对映选择性乙烯基迈克尔加成反应。由于催化剂通过同步的H键引导对乙烯基亲核试剂和亲电试剂的双重活化,已经完成了与β,γ-不饱和α-酮酸酯的具有挑战性的迈克尔反应。该反应以高收率提供产物,同时导致优异的立体控制(高达99%ee和> 19:1 E / Z)。
Enantioselective vinylogous aldol reaction of acylphosphonates with 3-alkylidene oxindoles
作者:Manish K. Jaiswal、Sanjay Singh、Ravi P. Singh
DOI:10.1039/d1ob00140j
日期:——
phosphonates has been described. The hydrogen bonding ability of the bifunctional thiourea catalyst allows simultaneous dual activation of a vinylogous oxindole nucleophile and an acylphosphonate electrophile, affording hydroxyphosphonato-3-alkylidene-2-oxindoles as aldol adducts in high yields (up to 92%) with excellent stereocontrol (up to 99% ee).
Catalytic enantioselective synthesis of chiral 4-hydroxy 4′-substituted pyrazolones by the vinylogous aldol reaction of pyrazole-4,5-diones with 3-alkylidene-2-oxindoles
作者:Krishna Kumar、Bhuvnesh Singh、Soumyadip Hore、Ravi P Singh
DOI:10.1039/d0nj05886f
日期:——
Here, a bifunctional quinine-derived benzamide catalyzed directenantioselective vinylogous aldol reaction between 3-alkylidene-2-oxindoles and pyrazole-4,5-diones has been developed. This challenging protocol has been achieved via the H-bonding dual activation mode of the catalyst. Highly functional rich pyrazolone moieties having an oxindole core have been obtained with an excellent E/Z (>19 : 1)
在这里,已经开发了一种双功能奎宁衍生的苯甲酰胺催化 3-亚烷基-2-羟吲哚和吡唑-4,5-二酮之间的直接对映选择性乙烯基醛醇反应。这一具有挑战性的协议是通过催化剂的 H 键双激活模式实现的。已获得具有 oxindole 核心的高功能性丰富吡唑啉酮部分,其E / Z (>19:1) 和高产率以及中等对映选择性。
Enantioselective Organocatalytic Three-Component Vinylogous Michael/Aldol Tandem Reaction among 3-Alkylidene oxindoles, Methyleneindolinones, and Aldehydes
作者:Jing-Xiang Xu、Yi-Syun Jiang、Chih-Hao Chen、Nadaraj Sathishkumar、Kai-Ti Chu、Ming-Hsi Chiang、Hsin-Tsung Chen、Jeng-Liang Han
DOI:10.1021/acs.joc.1c02180
日期:2022.1.7
We reported a one-pot enantioselective three-component vinylogous Michael/aldol tandem reaction of prochiral 3-alkylidene oxindoles with methyleneindolinones and aldehydes using bifunctional organocatalysts. A variety of enantioenriched 3,3-disubstituted oxindoles 3 and spirolactones 4 were generated in moderate yields (up to 78%) with high stereoselectivities (up to >20:1 dr, >99% ee). Intriguingly