catalyzed carbonylation of allenyl ketones has been investigated. Carbonylative dimerization predominantly proceeded to afford bis(3-furanyl)methanones 2 as the major products. The use of DMSO strikingly changed the course of the reaction, affording methyl 3-furancarboxylates 3 as the major products. DFT calculations revealed that DMSO stabilized the methanol-coordinated intermediate, leading to methoxycarbonylation
Tandem Michael Addition/Aldol Reaction of Allenic Ketones with Alkyl Vinyl Ketones: Versatile Synthesis of 2-Alkynyl 1,5-Diketones, 4-Alkynyl-3-hydroxycyclohexanones and 4-Alkynylcyclohexenones
作者:Deepika Malhotra、Le-Ping Liu、Gerald B. Hammond
DOI:10.1002/ejoc.201001161
日期:2010.12
alkynylenolate was investigated in the reactions of allenic ketones and vinylketones. We found that different products could be obtained under different conditions. The tetrabutylammonium fluoride (TBAF)-mediated Michael addition of allenic ketones to vinylketones gave 2-alkynyl 1,5-diketones as the product. Under stronger basic conditions, a tandem Michael addition/aldol reaction of the two starting materials
在烯酮和乙烯基酮的反应中研究了炔基烯醇酸酯的反应性。我们发现在不同的条件下可以得到不同的产品。四丁基氟化铵 (TBAF) 介导的烯酮与乙烯基酮的迈克尔加成得到 2-炔基 1,5-二酮产物。在强碱性条件下,两种原料在一锅内发生串联迈克尔加成/羟醛反应,低温下可分离出4-炔基-3-羟基环己酮,而室温下可得到4-炔基环己烯酮。应注意的是,即使使用乙基乙烯基酮作为迈克尔受体,也仅从反应中分离出一种 4-炔基-3-羟基环己酮的非对映异构体,如通过 1 H 和 13 C NMR 光谱测定。
<scp>Palladium‐Catalyzed</scp> Oxidative Alkynylation of Allenyl Ketones: Access to <scp>3‐Alkynyl</scp> Poly‐substituted Furans<sup>†</sup>
作者:Bowen Dou、Kang Wang、Jianbo Wang
DOI:10.1002/cjoc.202300465
日期:2023.12.15
bearing alkynyl substituents are highly useful in organic synthesis. However, the methodologies to access these important furan derivatives are rather limited. We herein report an efficient synthesis of alkynylated furan derivatives based on Pd-catalyzed oxidative cross-coupling reaction between allenyl ketones and terminal alkynes. This novel synthesis of alkynylated furans with wide substrate scope is operationally