Acid-catalysed formation of tricyclic N,S-acetals in imidazolinone series based on the use of the unprecedented N-acyliminium ion cascade reaction involving transposition, heterocyclisation and pi-cyclisation.
4-Hydroxy-5,5-dimethylimidazolines tethered at N-1 to an aryl sulfide undergo an unprecedented acid-catalysed domino reaction, involving double methyl transposition, heterocyclisation, isomerisation of thiazetidinium ion and, finally, pi-cyclisation. In this way a one-pot synthesis of original tricyclic N,S-acetals was developed. The same triheterocyclic products can be prepared also starting from the corresponding 5-hydroxy isomers (in this case the cascade of reactions does not involve methyl transposition).
Pesquet
Anthony
A
URCOM, EA 3221, UFRST de l'Université du Havre, B.P: 540, 25 rue Philippe Lebon, F-76058, Le Havre, France.
Daïch
Adam
A
Decroix
Bernard
B
Van Hijfte
Luc
L
D000080:Acetals / Q000138:chemical synthesis*; D002384:Catalysis; D003500:Cyclization; D006575:Heterocyclic Compounds, 3-Ring / Q000138:chemical synthesis*; D048288:Imidazolines / Q000138:chemical synthesis*
D000080:Acetals; D006575:Heterocyclic Compounds, 3-Ring; D048288:Imidazolines