Remarkable [3+2] Annulations of Electron-Rich Olefins with Unstabilized Azomethine Ylides

Herein we would like to communicate that an unstabilized azomethine ylide generated from commercial trimethylamine N-oxide will undergo a remarkable 1,3-dipolar cycloaddition in good yield with electron-rich and unpolarized olefins. A broad range of substituents on the alkenes are tolerated provided they are compatible with excess LDA. This demonstration of novel reaction scope should encourage others to try trimethylamine N-oxide as an azomethine ylide precursor in the synthesis of challenging 3,4-disubstituted pyrrolidines.