16900-64-4Relevant academic research and scientific papers
An unusual result of the reaction of α-acetylene aldehydes, pyridines, and malonic acid. Synthesis and structure of novel pyridine betaines
Golovanov, Aleksander А.,Dan’kov, Sergei А.,Sokov, Sergey А.,Melnikov, Pavel А.,Ukolov, Anton I.,Voronova, Evgeniya D.,Vologzhanina, Anna V.,Bunev, Aleksander S.
, p. 93 - 96 (2019/02/26)
[Figure not available: see fulltext.] 5-Aryl-2-carboxy-5-(pyridin-1-ium-1-yl)penta-2,4-dienoates, previously unknown pyridine betaines, were formed in 32–70% yields as a result of the reaction of arylpropynals, substituted pyridines, and malonic acid inst
Synthesis of 4-Ylidenebutenolides. A Practical Route to 2-En-4-ynoic Acid Intermediates based on Conjugate Addition of Alkynyl-lithium Reagents
Clemo, Nicholas G.,Pattenden, Gerald
, p. 2133 - 2136 (2007/10/02)
Conjugate addition of alkynyl-lithium reagents to diethyl ethoxymethylenemalonate, followed by simultaneous saponification and 1,2-elimination of ethanol from the intermediate adducts, viz (18), in the presence of ethanolic potassium hydroxide, provides a useful synthesis of substituted propargylidenemalonic acids (19).Cyclisation of the propargylidenemalonic acids, using known procedures then leads to the corresponding 4-ylidenebutenolides, e.g. (20) and (21)
