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。