74736-89-3Relevant academic research and scientific papers
NOVEL PHOTOREACTIONS OF CHROMENE DERIVATIVES. THE PHOTOLYSIS OF 4-ACETOXY-2H-CHROMENE.
Climent, Maria J.,Garcia, Hermenegildo,Miranda, Miguel A.,Primo, J.
, p. 999 - 1002 (1987)
The photolysis of 4-acetoxy-2H-chromene 1a leads to a mixture of o-acetoxyphenyl vinyl ketone 2a, 4-chromanone 3, chromone 4, 3-acetoxy-4-chromanone 5, 3-hydroxy-4-chromanone 6, and a cyclobutane dimer with anti head-to-head structure (7).The formation of 2a is explained by a photochemical electrocyclic opening of the pyran ring, followed by cis-trans photoisomerization and transacylation.Compounds 3 and 4 would arise from 1a by way of a photolytic cleavage of the acetyl-oxygen bond and subsequent disproportionation of the resulting radical 8.The isolation of the 3-substituted chromanones 5 and 6 can be accounted for in terms of a photochemical epoxidation of 1a.This process and the photodimerization are unprecedented in the photochemistry of 2H-chromenes.Moreover, the photochemical epoxidation of 1a could have biological significance.
