Oxabicyclo[3.2.1]octane derivatives as highly reactive dienophiles: synthesis of bicyclo[5.n.0] systems.
[reaction: see text] We have developed highly versatile, homochiral oxabicyclo[3.2.1]octadiene building blocks for the synthesis of natural products. We have found that these bridged alkenes undergo exceptionally facile Diels-Alder reactions and react faster than several well studied bicyclo[2.2.1]heptene dienophiles. The reaction proceeds with high levels of stereochemical control and in very good to excellent yields, providing access to bicyclo[5.4.0]undecane and bicyclo[5.3.0]decane systems. This reactivity is attributed to strain and homoconjugation effects.
Pelphrey
Phillip
P
Burke Laboratories, Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA.
Jasinski
Jerry
J
Butcher
Ray J
RJ
Wright
Dennis L
DL