157476-91-0Relevant academic research and scientific papers
A CONCISE ROUTE TO THE TETRACYCLIC CORE OF PHORBOL
Paquette, Leo A.,Sauer, Daryl R.,Edmondson, Scott D.,Friedrich, Dirk
, p. 4071 - 4086 (2007/10/02)
The tetracyclic ketone 17, which possesses a framework closely related to phorbol, has been prepared in enantiomerically pure condition.Condensation of the dichlorocerate derived from 3 with 2-chlorocyclohexanone leads to chlorohydrins 4 and 5 in a 1:1 ratio.Treatment of 5 with excess vinylmagnesium bromide delivers 7, thereby setting the stage for anionic oxy-Cope rearrangement to 9.Epoxidation of 9 and base-promoted cyclization of the α-isomer (15) under kinetically controlled conditions eventuates in the formation of 17.A companion set of reactions was performed on 4 with the result that hemiketal 11 is formed following transannular ring closure.Lastly, one of the first intramolecularly competitive anionic oxy-Cope rearrangements is described.
