Asymmetric Synthesis of Pyrrolo[2,1-a]isoquinoline Derivatives by 1,3-Dipolar Cycloadditions of Stabilized Isoquinolinium N-Ylides with Sulfinyl Dipolarophiles

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• 作者：Jose虂 Luis Garci虂a Ruano ; Alberto Fraile ; M. Rosario Marti虂n ; Gemma Gonza虂lez ; Cristina Fajardo ; Ana Mari虂a Marti虂n-Castro
• 刊名：Journal of Organic Chemistry
• 出版年：2011
• 出版时间：May 6, 2011
• 年：2011
• 卷：76
• 期：9
• 页码：3296-3305
• 全文大小：1091K
• 年卷期：v.76,no.9(May 6, 2011)
• ISSN：1520-6904

文摘

Enantiomerically pure pyrrolo[2,1-a]isoquinoline derivatives are obtained by 1,3-dipolar reactions of isoquinolinium azomethine ylides with enantiopure 3-p-tolylsulfinylacrylonitriles, tert-butyl (2E)-4,4-diethoxy-2-p-tolylsulfinylbut-2-enoate, and 5-ethoxy-3-p-tolylsulfinylfuran-2(5H)-ones. Reactions evolve through the anti conformation of the ylide with complete regioselectivity. The facial selectivity is completely controlled by the configuration of the sulfinyl sulfur for acyclic dipolarophiles, whereas it is high (dr 83/17 or 89/11) but controlled by the C-5 configuration for sulfinylfuranones. Complete endo selectivity is observed with cyclic dipolarophiles and substituted acrylonitriles, but it is low with butenoate. The sulfinyl group also exerts a positive influence on the dipolarophilic reactivity toward these ylides.