Radical Addition of 2-Iodoalkanamide or 2-Iodoalkanoic Acid to Alkenes with a Water-Soluble Radical Initiator in Aqueous Media: Facile Synthesis of<i>γ</i>-Lactones
Radical reactions in water or aqueous ethanol using a water-soluble radical initiator are described. Heating a mixture of 2-iodoacetamide and 5-hexen-1-ol in water at 75 °C in the presence of a water-soluble radical initiator, 4,4′-azobis(4-cyanopentanoic acid), afforded 5-(4-hydroxybutyl)dihydrofuran-2(3H)-one in 95% yield. The use of 2-iodoacetic acid in place of 2-iodoacetamide also gave the same γ-lactone in 93% yield. The reaction of 2-iodoacetamide with 1-octene in aqueous ethanol was initiated by 2,2′-azobis(2-methylpropanamidine) dihydrochloride to provide γ-decanolactone. Employing water as a solvent is crucial to obtain lactone in satisfactory yield.
Ru-Catalyzed Isomerization of Achmatowicz Derivatives: A Sustainable Route to Biorenewables and Bioactive Lactones
作者:Miroslav Dangalov、Adolfo Fernández-Figueiras、Martin A. Ravutsov、Ekaterina Vakarelska、Maya K. Marinova、Nuno R. Candeias、Svilen P. Simeonov
DOI:10.1021/acscatal.2c04867
日期:2023.2.3
A Ru-catalyzed isomerization of Achmatowicz derivatives that opens unexplored routes to diversify the biogenic furanic platform is reported. The mechanistic insights of this formally redox-neutral intramolecular process were studied computationally and by deuterium labeling. The transformation proved to be a robust synthetic tool to achieve the synthesis of bioderived-monomers and a series of 4-keto-δ-valerolactones
报道了 Achmatowicz 衍生物的 Ru 催化异构化,该异构化开辟了使生物源呋喃平台多样化的未开发途径。通过计算和氘标记研究了这种正式的氧化还原中性分子内过程的机理见解。该转化被证明是一种强大的合成工具,可实现生物衍生单体和一系列 4-酮基-δ-戊内酯的合成,进一步促进了合成乙酰基合成的灵活策略的发展。还描述了两种天然产物(即 ( S , S )-muricatacin 和 ( S , S )-L-因子)的简洁且无保护基团的不对称全合成。
Photoredox‐Catalyzed α−C−H Monoalkylation of Symmetric Polyols in the Presence of CO<sub>2</sub>
The transient carbonation of polyols under a CO2 atmosphere enables their C−H monoalkylation by photoredox catalysis. This reactivity results from an unprecedented C−H activation through intramolecular hydrogen bonding.