Home Products Cited in Publications Worldwide Are β-Lactones Involved in Carbon-Based Olefination Reactions?
Synlett,2024,35(10):1190-1194.
Jan Nowak; Michał Tryniszewski; Michał Barbasiewicz
Heteroatom-based olefinating reagents (e.g., organic phosphonates, sulfonates, etc.) are used to transform carbonyl compounds into alkenes, and their mechanism of action involves aldol-type addition, cyclization, and fragmentation of four-membered ring intermediates. We have developed an analogous process using ethyl 1,1,1,3,3,3-hexafluoroisopropyl methylmalonate, which converts electrophilic aryl aldehydes into α-methylcinnamates in up to 70% yield. The reaction plausibly proceeds through the formation of β-lactone that spontaneously decarboxylates under the reaction conditions. The results shed light on the Knoevenagel–Doebner olefination, for which decarboxylative anti-fragmentation of aldol-type adducts is usually considered.
olefination ; carbonyl compounds ; reaction mechanism ; lactones ; malonates ; Knoevenagel ; Doebner reaction