Synthesis of 1,3-diamines
Enantiopure azetidinium salts were treated with various nucleophiles (azide anion, benzylamine, acetate anion or alkoxides) which provided interesting insights into the regioselectivity of the ring-opening process.
F. Couty, O. David, F. Durrat, G. Evano, S. Lakhdar, J. Marrot, M. Vargas-Sanchez, Eur. J. Org. Chem., 2006, 3479-3490.
Intramolecular addition of tosylureas to allenes is highly syn-/anti-diastereoselective when employing a palladium or rhodium-based catalytic system and affords 1,3-cyclic ureas in excellent yields. The obtained tetrahydropyrimidinones are easily deprotected and modified.
A. G. A. Geissler, K. R. Riesterer, B. Breit, Org. Lett., 2021, 23, 9168-9172.