A solution of 1-adamantanol (0.304 g, 2 mmol)and urea (0.24 g, 4 mmol) in TFA (1.54 mL, 20 mmol) was heated at 115-120^oCfor 7 hr. After the reaction was complete, the mixture was kept at r.t.overnight. Then acetone (2 mL) was added to and precipitate was formed. Thecrude product was filtratrated after cooling, washed with pentane and dried togive 0.43 g target compound (83%).

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