| Summary: | 碩士 === 國立臺灣師範大學 === 化學研究所 === 89 === The addition of carbon nucleophiles at 25℃ to (h4-1,3-cyclohexadiene)Fe(CO)3 complex followed by hydride abstraction with Davis reagent produces C-5 substituted (h4-1,3-cyclohexadiene)Fe(CO)3 complexes as the major products. With acyclic diene-
iron complexes, the addition gave predominantly terminal nucleophilic-substituted (h4-
1,3-diene)Fe(CO)3 complexes. The silicon anion (LiSiMe2Ph) is capable of addition and afford silicon-substituted iron-complex. The reaction path is similar to that of carbon nucleophiles. Quenching the reactive intermediate with trifluoroacetic acid or bromines generated organosilicon compounds.
Intramolecular addition of ester enolate to iron-complex with an ether linkage at the C-2 position of the diene generates g-lactones as the major product. The reaction involved first addition/elimination followed by intramolecular transesterfication to give the g-lactones.
Complexation of acyclic dienes, carrying a (1S)-(+)-ketopinoxy as the chiral auxiliary, with Fe2(CO)9 proceeds in a completely diastereoselective fashion to afford diene-iron complexes in moderate yields. When (1R)-(-)-ketopinoxy was used as the chiral auxiliary, the opposite enantioisomeric complexes are isolated as a single diastereomer in comparable yield and specific rotation. The stereochemistry of chiral acyclic diene-iron complexes is determined by single-crystal X-ray methods.
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