Synthesis of unsaturated lactones via palladium-catalyzed cyclization of alkenoic acids
摘要:
Acyclic and cyclic, aliphatic or aromatic, 4- or 5-alkenoic acids cyclize in high yield to 5- or 6-membered unsaturated lactones using 5 mol % Pd (OAc) 2, 2 equiv of NaOAc, and 1 atm Of O2.
The present invention provides a fragrance precursor of formula I:
1
that is capable of forming a fragrant ketone of formula II:
2
and a fragrant lactone of formula III:
3
Synthesis of vinylic lactones via palladium-catalyzed coupling of vinylic halides or triflates and unsaturated carboxylic acids
作者:Richard C. Larock、David J. Leuck、L.Wayne Harrison
DOI:10.1016/s0040-4039(00)82356-4
日期:1988.1
Vinylic halides or triflates react with 3-butenoic or 4-pentenoic acids in the presence of 5% Pd(OAc)2 or Pd(dba)2, -Bu4NCl, -PrNEt2 and either acetonitrile or ,-dimethylformamide at 80–100°C to afford the corresponding γ-alkenyl-γ-butyro- or δ-alkenyl-δ-valerolactones respectively by an intramolecular π-allylpalladium displacement process.