A Dienyl Boronate-Aryl Nitroso Ene Reaction Entry to C-Pyrrolyl Nitrones and Subsequent Conversion to Isoxazolidines
Abstract
A new cascade reaction to access C-pyrrolyl nitrones en route to isoxazolidines is reported; a process that involves four successive steps, the first key step being an ene-reaction of a 3-methyl-1,3-dienylboronate ester with an aryl nitroso compounds to derive uncommon 1,3-dipoles which react with various alkenes to access isoxazolidines. The scope and mechanism of the cascade sequence is discussed.