Synthesis of 3-adamantylated hydantoins and their 2-thio(seleno) analogs

A series of 3-(adamantan-1-ylalkyl)-2-(O,S,Se)hydantoins were synthesized in the reaction of (adamantan-1-ylalkyl)heteroallenes with glycine ethyl ester hydrochloride under mild conditions in 75–85% yields. A method was developed for the synthesis of novel adamantan-1-ylalkyl isoselenocyanates, precursors in the synthesis of adamantylated 2-selenohydantoins. For the first time, 3-(adamantan-1-yl)-2-(O,S)hydantoins were synthesized via the reaction of 2-(O,S)hydantoins with 1,3-dehydroadamantane in 1,4-dioxane heated to reflux for 1 h in 75–80% yields.