Preparation of Cobaloxime-Substituted Unsaturated Carbonyl Compounds and Their Subsequent Conversion into 1-Cobaloxime-Substituted 1,3-Dienyl Complexes

Reduced cobaloxime (cobaloxime = [(pyridine)(dimethylglyoxime)2cobalt]) compounds react with a variety of oxygen-substituted allenic and propargyl electrophiles to produce cobaloxime-substituted α,β- or β,γ-unsaturated ketones and aldehydes. Two of the new unsaturated acyl complexes prepared have been characterized by X-ray crystallography. Several of the α,β-unsaturated acyl complexes were subsequently converted into 1-cobaloxime-1,3-dienyl complexes using Peterson or Petasis olefinations. One of these new dienyl complexes has also been characterized by X-ray crystallography.