Ym. Wang et al., PHOTOCHEMISTRY OF NONCONJUGATED BICHROMOPHORIC SYSTEMS .3. SYNTHESIS AND PHOTOREACTION OF POLY(ETHYLENE GLYCOL) BISCOUMARINYLOXYACETATES, Chinese journal of chemistry, 15(2), 1997, pp. 169-173
A series of poly(ethylene glycol) biscoumarinyloxyacetates have been s
ynthesized and their intramolecular photochemical cyclodimerizations h
ave been studied. It was found that only syn-HT configuration products
were obtained when these bisesters were directly irradiated in chloro
form, and the yields of the products decreased with the increase of th
e chain length. This photocyclization reaction is a convenient and eff
ective method to synthesize macrocyclic compounds.