The diastereoselectivity of the photocycloaddition of benzaldehyde to furan was determined (exo/ endo ) 212:1) and compared with the reaction of other carbonyl compounds and carbonyl analogues. These results were compared with Paternò-Bü chi reactions of cycloalkenes and cyclic enol ethers. An increase in steric demand of the R-substituent in benzoyl compounds led to a change in exo/ endo-selectivity for furan cycloadditions that was not observed for cycloalkenes or cyclic enol ethers. Different ISC-reactive conformers with enhanced spin-orbit coupling are postulated as a reasonable explanation for the stereoselectivities observed. Additionally, solvent effects were studied, demonstrating the influence of photoinduced electron-transfer steps on the regio-and diastereoselectivity of Paternò-Bü chi reactions with 2,3-dihydrofuran in polar solvents. Two bicyclic oxetanes (8 and 10) were characterized by X-ray structure analysis.

No abstract

No abstract

No abstract

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.