Synthesis of 1,3-syn and -anti-Tetrahydro-pyrimidinones

Significance

The methodology described in this article allows the selective formation of syn- and anti-1,3-tetrahydropyrimidinones using an intra­molecular palladium-catalyzed allylic substitution. Depending on the applied reaction conditions, both diastereomers could be prepared starting from a precursor of type 1 in a diastereodivergent fashion in excellent yields and good selectivities. Furthermore, it has been shown that a stepwise deprotection of the syn and anti products towards the free 1,3-diamines could be achieved in a very efficient manner.