Studies on the stereochemical assignment of 3-acylidene 2-oxindoles
作者:Steven J. Edeson、Julong Jiang、Stephen Swanson、Panayiotis A. Procopiou、Harry Adams、Anthony J. H. M. Meijer、Joseph P. A. Harrity
DOI:10.1039/c4ob00496e
日期:——
The designation of E/Z-geometrical isomers in 3-acylidene 2-oxindoles by NMR spectroscopy can lead to erroneous assignment of alkene stereochemistry because of the narrow chemical shift range observed over a large series of analogues. In contrast, UV-Vis spectroscopy offers a convenient and more reliable method for alkene stereochemical assignment. A combination of X-ray crystallography and theoretical studies shows that the observed differences in UV-Vis spectroscopic behaviour relate to the twisted conformation of the Z-isomers that provides reduced conjugation and weaker hypsochromic (blue-shifted) absorbances relative to those of the E-isomers.
Asymmetric Synthesis of Spirooxindoles with Seven Stereocenters via Organocatalyzed One‐pot Three‐component Sequential Cascade Reactions
作者:Bo‐Liang Zhao、Da‐Ming Du
DOI:10.1002/adsc.201900218
日期:2019.7.11
three‐component Michael/Mannich‐Michael/cyclization sequential cascade reaction for the construction of bispirooxindole‐spirooxindoles was developed in good yields with excellent stereoselectivities (up to >20:1 dr, 99% ee). A series of original cinnamoyl‐3‐ylideneoxindoles have been applied to this sequential cascade strategy for the first time. This new strategy provides a process for the enantioselective construction
Synthesis of (<i>E</i>)-3-(2-Oxo-2-arylethylidene)indolin-2-ones through Alkyne Carbonyl Metathesis and Their Stereospecific Application towards Spiro-oxindolopyrrolizidine Scaffolds
作者:Soumyadip Basu、Chhanda Mukhopadhyay
DOI:10.1002/ejoc.201701606
日期:2018.3.29
A transition metal salt catalyzed alkyne carbonyl metathesis followed by a multicomponent protocol to synthesize highly substituted new (1′S,2′R,3′R,7a′R)‐1′,3′,5′,6′,7′,7a′‐hexahydrospiro[indoline‐3,2′‐pyrrolizin]‐2‐ones. A total of 39 compounds were synthesized by an interesting combination of metal‐salt catalysis and a multicomponent strategy.
Ultrasonic assisted-silica mediated [3+2] cycloaddition of azomethine ylides—a facile multicomponent one-pot synthesis of novel dispiroheterocycles
作者:A.R. Suresh Babu、R. Raghunathan
DOI:10.1016/j.tetlet.2007.07.085
日期:2007.9
An efficient synthesis of dispiro-oxindolopyrrolizidine and dispirooxindolothienopyrrole derivatives has been expediently accomplished via a one-pot, three-component 1,3-dipolar cycloaddition reaction. High regioselectivity was achieved on ultrasonication in the presence of silica as a catalyst. X-ray diffraction studies of one of the cycloadducts proved the structure and regiochemistry of the cycloaddition
Regioselective Synthesis of Novel Dispiro‐oxindoloindenoquinoxaline Pyrrolidines through 1,3‐Dipolar Cycloaddition Methodology
作者:A. R. Suresh Babu、R. Raghunathan
DOI:10.1080/00397910801914327
日期:2008.4
Abstract A facile and efficient regioselectivesynthesis of dispiroindenoquinoxaline pyrrolidine derivatives by a one‐pot four‐component 1,3‐dipolar cycloaddition reaction is delineated.