Imidazolidine-2-selones

Se-Se-bridged dications with halide or interhalide anions can be obtained under certain conditions by halogenation of 4-imidazoline-2-selones and 4-imidazolidine-2-selones. In the solid salts, Se-Se-bridged dications exhibit significant interactions with their anions, depending on the number and the... 

General methods for preparation of imidazolidin-4-one-2-thiones include the reaction of thioureas with a-dicarbonyl compounds,37,38 with ethyl phenylpropiolate,39 and with phenyl chlorothiolacetate,40 and cyclization in acid of l-(carbethoxymethyl)-2-thioureas.41 The analogous reaction of a-diearbonyl compounds with selenoureas produce imidazolidin-4-one-2-selones.42 Berlin and Levi43 utilized the acid-catalyzed cyclization of l-aryl-3-carbalkoxymethyl-2-thioureas to produce 3-arylimidazolidin-4-one-2-thiones (23). 

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