Synfacts 2007(2): 0145-0145  
DOI: 10.1055/s-2006-955825
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart · New York

Palladium-Catalyzed Synthesis of Lactones and Lactams in Ionic Liquids

Contributor(s): Victor Snieckus, Bärbel Wittel
F. Ye, H. Alper*
University of Ottawa, Canada
Further Information

Publication History

Publication Date:
23 January 2007 (online)

Significance

The synthesis of 5-, 6-, and 7-membered ring lactones and lactams by Pd-catalyzed cyclocarbonylation of 2-allylphenols, 2-allyl­anilines, 2-vinylphenols and 2-aminostyrenes in ionic liquids is reported. The products are formed in good to excellent selectivities and yields. Interestingly, in the first series, 6-membered ring B is favored over 5-membered ring A formation while in the second reaction, 6- and 7-membered rings D and E are predominantly formed. Of the several reaction conditions that were tested, Pd2(dba)3, dppb in [BMIM][PF6]or [BMIM][NTf2] were shown to be the best. The ionic liquid, containing the palladium catalyst and ligand was shown to be recyclable.