Synthesis of Functionalized
Dialkyl Cyclobutane-1,1-dicarboxylates and Alkyl 5,6-Dihydro-4<i>H</i>-pyran-3-carboxylates via Michael-Induced
Ring Closure of δ-Chloro-α,β-Unsaturated
Diesters and Ketoesters
作者:Norbert De Kimpe、Sven Mangelinckx、Bruno Vermaut、Roland Verhé
DOI:10.1055/s-0028-1083506
日期:——
2-(3-chloro-2,2-dimethylpropylidene)malonate, upon treatment with sodium tert-butylthiolate, sodium methoxide or sodium cyanide in methanol, provided a short and efficient synthesis of new 2-functionalized cyclobutane-1,1-dicarboxylic esters. Under similar conditions, methyl 2-acetyl-5-chloro-4,4-dimethylpent-2-enoate afforded 4-functionalized methyl 5,6-dihydro-4H-pyran-3-carboxylates as the MIRC products
2-(3-氯-2,2-二甲基亚丙基)丙二酸二甲酯的迈克尔诱导闭环 (MIRC),在用叔丁硫醇钠、甲醇钠或氰化钠的甲醇溶液处理后,提供了一种简短有效的新 2 -官能化的环丁烷-1,1-二羧酸酯。在类似条件下,2-乙酰基-5-氯-4,4-二甲基戊-2-烯酸甲酯得到 4-官能化的 5,6-二氢-4H-吡喃-3-羧酸甲酯作为 MIRC 产物。