Completely diastereoselective tricarbonyliron complexation reactions of chiral dienes

Complexation of cylic and acyclic dienes, carrying a (1S)-(+)-ketopinoxy as the chiral auxiliary, with nonacarbonyldiiron proceeds in a completely dia stereoselective fashion to afford diene-iron complexes in moderate yields. When (1R)-(-)-ketopinoxy was used as the chiral auxiliary, the opposite ena ntioisomeric complexes are isolated as a single diastereomer in comparable yield and specific rotation in each case. The stereochemistry of chiral cyc lic and acyclic diene-iron complexes is determined by single-crystal X-ray methods.