A short protocol for the synthesis of spirocyclic tetrahydrofurans via intramolecular O–H insertion
摘要:
The conversion of cyclic ketones to functionalised spirocyclic tetrahydrofurans via a three-step sequence of acetoacetate ester dianion-aldol reaction, diazo-transfer and carbene O-H insertion is described. (C) 2001 Elsevier Science Ltd. All rights reserved.
A treatment of ethyl bromoacetate with two molar equivalent of samarium diiodide at −50 °C for 15 min in THF produces a β-oxoester enolate equivalent; the reagent reacts with ketones or aldehydes to give δ-hydroxy-β-oxoesters in excellent yields.
将乙基溴乙酸酯在 -50 °C 下与两摩尔当量的二碘钕处理 15 分钟,使用 THF 作为溶剂,产生β-氧酯烯醇等效物;该试剂与酮或醛反应,能够以优异的产率生成δ-羟基-β-氧酯。
Utimoto, Kiitrio; Takai, Tsutomu; Matsui, Toshiki, Bulletin de la Societe Chimique de France, 1997, vol. 134, # 3-4, p. 365 - 370
A short protocol for the synthesis of spirocyclic tetrahydrofurans via intramolecular O–H insertion
作者:Keith Jones、Teymour Toutounji
DOI:10.1016/s0040-4020(01)00097-7
日期:2001.3
The conversion of cyclic ketones to functionalised spirocyclic tetrahydrofurans via a three-step sequence of acetoacetate ester dianion-aldol reaction, diazo-transfer and carbene O-H insertion is described. (C) 2001 Elsevier Science Ltd. All rights reserved.
Regioselective Addition of 1,3-Dicarbonyl Dianions to Carbonyl Compounds: One Pot Lactonization and Ketalization of δ-Hydroxy-β-keto Esters to Protected Pyrone Derivatives
作者:Manas K. Ghorai、Sandipan Halder、Sauvik Samanta
DOI:10.1071/ch12062
日期:——
strategy for the synthesis of 6-substituted-2-pyrone derivatives, by BF3·OEt2 mediated one pot cyclization and keto-protection of δ-hydroxy-β-keto esters, obtained via regioselective addition of 1,3-dicarbonyl dianion of ethyl acetoacetate to aldehydes and ketones is described.