628716-55-2Relevant academic research and scientific papers
Enantioselective Diels-Alder reactions of α-fluorinated α, β-unsaturated carbonyl compounds Part 5. Chemical consequences of fluorine substitution
Essers, Michael,Ernet, Thomas,Haufe, Günter
, p. 163 - 170 (2003)
α-Fluoro-α,β-unsaturated carbonyl compounds, compared with the corresponding non-fluorinated parent compounds, are less reactive in Diels-Alder reactions with normal 1,3-dienes. The cycloadducts of such dienophiles with 2,3-dimethylbutadiene (1) or o-quin
Diastereoselective Diels-Alder reactions of α-fluorinated α,β-unsaturated carbonyl compounds: Chemical consequences of fluorine substitution. 2
Essers, Michael,Mueck-Lichtenfeld, Christian,Haufe, Guenter
, p. 4715 - 4721 (2007/10/03)
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 synthesized and subjected to Diels-Alder reactions with cyclopentadiene. The cycloadditions were conducted thermally, microwave-assisted, and Lewis acid-mediated (TiCl4). The fluorinated dienophiles exhibited a lower reactivity and exo diastereoselectivity, while the corresponding nonfluorinated parent compounds reacted endo selectively. DFT calculations suggest that kinetic effects of fluorine determine the stereoselectivity rather than higher thermodynamic stability of the exo products.
