ne o&wed substituent-dependent regioseiectiviLy f&Z-vs I,l-additionl iir the &cmphil& ma&~~ of antbiaknt imines 1-3 B mtioMl& undemood &Y the relative m@fnitude of the LUMO coelpriena of the Mnes. We have recently reported the succemful chiral ~g~-m~a~ ~~ 1,2-and l,~a~tion reactions of organolithiums to various imines of aryl and a#-unsaturated aldehydes.1 Thus, organolithiums add to the cyclohexylimmes 1.2 (R=c-c6H11) in 1.4fashion to give, after hydrolysis, the oorresponding aldehydes in up to 99% ee and in high to good yield& On the other hand, the reactions with arylimines 1, 2 (R--Q-MeOPh) exclusively afford 1,2-adducts in up to 99% ee and in nearly quantitative yields, giving us a good methcd for the preparation of chiral atnines.3.4 It is also interesting in that the reactions with both cyclohexyl-and arylimines of 1-fluo~naph~alene-2-c~bal~hy~ 3 exclusively proceed in 1,4-fashion to provide nucleophik aromatic substitution products in high yields,5 Since deep understanding of the factors governing regioselectivity is a long-standing problem6.7 and essential for further development of the much more effective catalytic asymmetric reactions of the eneimines, we carried out molecular orbital calculations of l-3.8 AR s-cis and s-tram &rwtum 1,2 were fully optimized with the ab initio (HWSTO-3G) method