Creation of new types of multifunctional compositions based on crotonaldehyde

The aldol condensation reaction is one of the most powerful and versatile synthetic methods in organic chemistry and has been extensively studied to optimize conditions, minimize side reactions, and understand stereochemical outcomes.Among various substrates, 1,5-diketones have emerged as valuable participants due to their accessibility and reactivity, especially for synthesizing heterocyclic and carbocyclic compounds.Notably, the 1,5-diketone motif plays an important role in constructing the A ring of steroids.Involvement of 1,5-diketones in aldol condensation has enabled the synthesis of new carbo-and heterocycles and clarified the formation pathways of pyrylium salts.However, some types of 1,5diketones, particularly "semicyclic" ones -where one carbonyl group is in a ring and the other is exocyclic -have not been sufficiently studied.These asymmetrical cycloaliphatic 1,5-diketones present different reactive centers, raising questions of regiospecificity and regioselectivity, which create opportunities for constructing new molecular architectures.Addressing these challenges opens perspectives for expanding the chemistry of this compound class.1,5-Diketones are important intermediates in organic synthesis thanks to their availability and versatile reactivity, serving as convenient starting materials for carbocyclic compounds.Several methods exist for their preparation, with one main route being the Michael reaction, often catalyzed by bases or lithium perchlorate, and sometimes assisted by ultrasound.A known variant, the Robinson annulation, also effectively yields these diketones