title: Synthesis of 1,2,4-trioxepanes and 1,2,4-trioxocanes via photooxygenation of homoallylic alcohols.
abstract: Homoallylic alcohols 4a-d, easily accessible in two steps from cyclopropyl methyl ketone, underwent a highly regioselective reaction with singlet oxygen to yield gamma-hydroxyhydroperoxides 5a-d in 57-72% yield. Acid-catalyzed reaction of 5a-d with acetone, cyclopentanone, and cyclohexanone furnished 1,2,4-trioxepanes 8a-d, 9a-d, and 10a-d in good yields. Homoallylic alcohol 12 also underwent a highly regioselective photooxygenation to yield gamma-hydroxyhydroperoxide 13 in 67% yield, which on reaction with acetone, cyclopentanone, and cyclohexanone, furnished 1,2,4-trioxocanes 16-18 in 41-55% yield.
authors.affiliation: Division of Medicinal and Process Chemistry, Central Drug Research Institute, Lucknow-226001, India. chandancdri@yahoo.com
authors.forename: Chandan
authors.initials: C
authors.lastname: Singh
authors.forename: Shilpi
authors.initials: S
authors.lastname: Pandey
authors.forename: Gunjan
authors.initials: G
authors.lastname: Saxena
authors.forename: Nisha
authors.initials: N
authors.lastname: Srivastava
authors.forename: Malvika
authors.initials: M
authors.lastname: Sharma
mesh_terms: D002384:Catalysis; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010777:Photochemistry; D020005:Propanols / Q000737:chemistry*; D026082:Singlet Oxygen / Q000737:chemistry*
chemical_list: D020005:Propanols; D026082:Singlet Oxygen; C006463:allyl alcohol