The stereochemistry of organometallic compounds. XXVII nucleophilic and electrophilic substitution reactions of conformationally restricted arenechromium compounds

The regioselectivity of reaction of tricarbonyl(1, 1-dimethylindane)chromium with selected electro- philes and nucleophiles has been shown to be influenced by the preferred conformation of the tri- carbonylchromium group. Nucleophiles preferentially react at carbon atoms eclipsed by a chromium- carbonyl bond and electrophiles at carbon atoms in staggered positions. When similar reactions were attempted with some chelated arenechromium dicarbonyl phosphorus compounds only low yields of substitution products were obtained.