Efficient access to chiral trans-2,6-dialkyl-1,2,5,6-tetrahydropyridines via allylation of chiral imines and ring-closing metathesis

Enantiomerically pure trans-2,6-dialkyl-1,2,5,6-tetrahydropyridines are synthesized in five steps from Garnerʹs aldehyde in 37–44% overall yield. This strategy is based on the allylation of chiral iminoalcohols formed in situ followed by a ring-closing metathesis.