| Abstract
| - Two α-fluoro α,β-unsaturated carbonyl compounds, i.e., benzyl 2-fluoroacrylate (3) and 2-fluorooct-1-en-3-one (4), as well as the corresponding nonfluorinated parent compounds, were synthesizedand subjected to Diels−Alder reactions with cyclopentadiene. The cycloadditions were conductedthermally, microwave-assisted, and Lewis acid-mediated (TiCl4). The fluorinated dienophilesexhibited a lower reactivity and exo diastereoselectivity, while the corresponding nonfluorinatedparent compounds reacted endo selectively. DFT calculations suggest that kinetic effects of fluorinedetermine the stereoselectivity rather than higher thermodynamic stability of the exo products.
|
