Bis-cyclopropanated 1,3,5-tricarbonyl compounds were prepared by a sequence of Claisen condensations and cyclopropanations. The optimization of the conditions proved to be very important to suppress retro-Claisen reactions. The conformation of these molecules was studied by experimental and computational methods. The syn/syn;syn/syn conformation is present for all derivatives. It is exclusively present in the case of the derivative containing a phenyl group located at the terminal carbon atom. In most cases, equilibria with other conformers are found.

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Functionalized indolizines were prepared by Lewis acid‐catalyzed cyclizations of 3‐(pyridin‐2‐yl)‐propiolates with enones. This new type of reaction provides a convenient and regioselective approach to ester‐substituted indolizine derivatives which are not readily available by other methods. Based on density function theory (DFT) calculations, a mechanism of the reaction has been suggested.

Pyrazoles and isoxazoles with cyclopropanated side‐chain were prepared by cyclization of cyclopropanated 1,3,5‐tricarbonyl compounds with hydrazine and hydroxylamine, respectively. The regioselectivity is influenced by the reaction conditions.

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