title: Cyclization cascades initiated by 1,6-conjugate addition.
abstract: Dienyl diketones containing tethered acetates selectively undergo two different 1,6-conjugate addition-initiated cyclization cascades. One is a 1,6-conjugate addition/cyclization sequence with incorporation of the nucleophile, and the other is catalyzed by DABCO and is thought to proceed via a cyclic acetoxonium intermediate. The reaction behavior of substrates lacking the tethered acetate was also studied. The scope of both types of cyclization cascades, the role of the amine additive, and the factors controlling reactivity and selectivity in the two different reaction pathways is discussed.
authors.affiliation: Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
authors.forename: Joshua L
authors.initials: JL
authors.lastname: Brooks
authors.forename: Alison J
authors.initials: AJ
authors.lastname: Frontier
mesh_terms: D000085:Acetates / Q000737:chemistry; D002384:Catalysis; D003500:Cyclization; D007659:Ketones / Q000737:chemistry*; D010879:Piperazines / Q000737:chemistry
chemical_list: D000085:Acetates; D007659:Ketones; D010879:Piperazines; C007306:triethylenediamine