title: [2 + 2] Photochemical cycloaddition/ring opening of 6-alkenyl-2,3-dihydro-4-pyridones.
abstract: During the course of a study aimed at constructing azaspirocycles from 2,3-dihydro-4-pyridones, an unexpected product was obtained in the SET ring-opening reaction of photocycloadduct 1. Differences in reactivity between homologues 1 and 2 were observed in the presence of SmI(2). Tricyclic ketone 2 afforded azaspiro[5.5]undecane 15 when treated with SmI(2); however, when ketone 1 was submitted to similar reaction conditions a double ring-opening/reduction sequence gave cis-piperidinol 10.
authors.affiliation: Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: Sahn
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Comins
mesh_terms: D003500:Cyclization; D015394:Molecular Structure; D010777:Photochemistry; D011728:Pyridones / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D011728:Pyridones