The 3-aza-Cope rearrangement of the N-alkyl-N-allylenamines derived from isobutyraldehyde, which proceeds thermally at 250" C, has been accelerated by a variety of electrophilic reagenta to give y, 6-unsaturated imines. Protic acids, such as HCl (0.5 equiv), and the Lewis acidic reagents Tic4 (0.1-0.2 equiv), Ek0. BF3 (0.5 equiv), and M e 3 (1.0 equiv) produced complete [3, 3] rearrangement of substrates at 111" C. By increasing the ...