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The reaction ~). /" o,clopenta(hexa)

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New synthetic opportunities of conjugated and saturated β-aminoketones were revealed consisting in heterocyclization reactions with the formation of spirochromenes and hydropyrimidinethiones. Alicyclic conjugated Mannich bases under conditions of basic catalysis suffer deamination followed by [4+2]cycloaddition leading to the stereo-and regiodirected formation of difficultly available spirochromene derivatives. Three-component condensation of acyclic and alicyclic Mannich ketones with thiourea and aromatic aldehydes under aprotic acid catalysis afforded functionalized derivatives of pyrimidine-2-thione series. Optimum conditions were found for О,N-heterocyclization of β-aminocarbonyl substrates.

For the first time, arylmethylidene cyclohexanones that are non-symmetrical due to the presence of peripheral substituents were studied in 1,3-dipolar cycloaddition reactions. It is shown that the interaction with the azomethine ylide generated from sarcosine proceeds regio- and diastereoselectively, with the participation of two non-equivalent parts of the dipolarophile. Also for the first time, β-amino ketones (Mannich bases) were used as dipolarophile equivalents of unsaturated ketones. It was found that cycloaddition occurs diastereoselectively at the generated center.