Synthesis 2021; 53(16): 2897-2902
DOI: 10.1055/a-1477-6043
paper

Wittig Reactions of Maleimide-Derived Stabilized Ylides with Alkyl Pyruvates: Concise Approach to Methyl Ester of (±)-Chaetogline A

Santosh V. Shelar
a   Division of Organic Chemistry, National Chemical Laboratory (CSIR), Pune, 411 008, India
b   Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
,
a   Division of Organic Chemistry, National Chemical Laboratory (CSIR), Pune, 411 008, India
b   Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
› Institutsangaben
N.P.A. thanks Science and Engineering Research Board (SERB), New Delhi, for financial support.


Abstract

A facile synthesis of methyl ester of chaetogline A is reported starting from the corresponding methyl 1-methyltryptophanate-derived­ maleimide. A stereoselective Wittig olefination with a carbonyl function in methyl pyruvate followed by phosphorous pentoxide-induced­ regioselective dehydrative cyclization are the essential reactions. An acid-induced thermodynamically driven stereoselective β- to α-position migration of the exocyclic C=C bond unit in ethyl tetrahydroindolizinoindolylidenepropanoate is described.

Supporting Information



Publikationsverlauf

Eingereicht: 09. März 2021

Angenommen nach Revision: 08. April 2021

Accepted Manuscript online:
08. April 2021

Artikel online veröffentlicht:
03. Mai 2021

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