Beilstein J. Org. Chem.2007,3, No. 14, doi:10.1186/1860-5397-3-14
), followed by 1,5-H migration in 8a. [21]
The spiropyrans 6 (R = H) bearing cyclopropanes are the secondary photoproducts formed as a result of the further reorganization of 5 (R = H), through a ringcontraction-ring expansion mechanism. [22][23] The formation of acetylcyclopropane compound 7 (R = CH3) from
PDF
Graphical Abstract
Scheme 1:
Synthesis of 3-Cycloalkenyloxybenzopyrans.