Diastereo‐ and Enantioselective Synthesis of Chiral Pyrrolidine‐Fused Spirooxindoles via Organocatalytic [3+2] 1, 3‐Dipolar Cycloaddition of Azomethine Ylides with Maleimides. Issue 11 (29th July 2015)

• Record Type: Journal Article
• Authors: Zhao, Hong‐Wu; Yang, Zhao; Meng, Wei; Tian, Ting; Li, Bo; Song, Xiu‐Qing; Chen, Xiao‐Qin; Pang, Hai‐Liang
• Is Part Of: Advanced synthesis & catalysis. Volume 357:Issue 11(2015)
• Page Start: 2492
• Page End: 2502
• Publication Date: 2015-07-29
• Subjects: Catalysis -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Chemistry -- Periodicals; Chemistry, Technical -- Periodicals; Chemistry -- Periodicals; Catalysis -- Periodicals; Technology, Pharmaceutical -- Periodicals; 547.2
• DOI: 10.1002/adsc.201500162
• Languages: English
• ISSNs: 1615-4150

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>In the presence of a <italic>Cinchona</italic> alkaloid‐based squaramide organocatalyst, the [3+2] cycloaddition of isatin‐derived azomethine ylides with maleimides proceeded readily, thus delivering the desired pyrrolidine‐fused spirooxindoles in 61–89% yields with &gt;20:1 <italic>dr</italic> and 12 to &gt;99 % <italic>ee</italic>. The absolute configuration of 5‐chloro‐1, 5′‐dimethyl‐3′‐phenyl‐3′, 3a′‐dihydro‐2′<italic>H</italic>‐spiro[indoline‐3, 1′‐pyrrolo[3, 4‐<italic>c</italic>]pyrrole]‐2, 4′, 6′(5′<italic>H</italic>, 6a′<italic>H</italic>)‐trione was unambiguously determined by means of X‐ray single crystal structure analysis. The reaction mechanism was hypothesized to account for the enantioselective formation of 5‐chloro‐1, 5′‐dimethyl‐3′‐phenyl‐3′, 3a′‐dihydro‐2′<italic>H</italic>‐spiro[indoline‐3, 1′‐pyrrolo[3, 4‐<italic>c</italic>]pyrrole]‐2, 4′, 6′(5′<italic>H</italic>, 6a′<italic>H</italic>)‐trione.</p> <p> <graphic position="anchor" mimetype="image" xlink:href="ark:/27927/pgj2cqp6314" orientation="portrait" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /> </p> </abstract>