The asymmetric induction in the complexation reaction of (S)‐1‐methyl‐2‐(5‐methyl‐cyclohexa‐1,4‐dienylmethyloxy)‐pyrrolidine 5 and (S)‐2‐(2‐N,N‐dimethylamino‐1‐propanoxy)‐5‐methylcyclohexa‐1,4‐diene 6 having heteroatom adjacent the stereogenic center has been investigated. The diastereoselectivity was determined directly from the diastereotopic peaks in the 1H NMR or by chemical correlation with 9. The conversion of η‐1,4‐complexes 7a and 8a to 9 proceeded with high retention of configuration while that of the η‐2,5‐Fe(CO)3 complexes 7b and 8b undergoes considerable racemization.