Diastereoselective hydrochlorination of acrylylurea derivatives using titanium tetrachloride and alcohol. Chelation-controlled Michael addition of chloride and intramolecular proton transfer to the alpha-position

Titanium tetrachloride and 2-propanol were used to analyze the diastereoselective hydrochlorination of acrylylurea and the titanium species in TiCl4 chelates which contain a pair of carbonyl oxygens. The amide proton experiences an intramolecular transfer to the Cl ligands on titanium. The methodology employed enhances diastereoselectivity, facilates identification of the absolute chemistry and explains the process of hydrochlorination.