(E)-alpha-substituted gamma-alkoxyallylboronic esters as new reagents: synthesis and reactivity toward aldehydes.
We have developed a synthesis of new allylboration reagents based on an allylic rearrangement. This approach led to the alpha-substituted gamma-alkoxyallylboronates 2 with a high stereoselectivity in favor of the E-isomer, independent of the organometallic used. We have also studied the reactivity of these reagents toward aldehydes, showing that the allylboration reaction occurs with an excellent diastereoselectivity to give the anti-diol derivatives 5. Moreover, the sequence can be carried out in a "one-pot" procedure avoiding the purification of allylboronates.
Possémé
Françoise
F
Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France.
Deligny
Michael
M
Carreaux
François
F
Carboni
Bertrand
B