Accession Number : AD0289022

Title :   MECHANISM OF ELECTROPHILIC SUBSTITUTION OF FERROCENES

Corporate Author : BRANDEIS UNIV WALTHAM MASS

Personal Author(s) : ROSENBLUM,MYRON

Report Date : 24 OCT 1962

Pagination or Media Count : 1

Abstract : Two mechanisms by which metallocenes undergo electrophilic substitution will be considered. The first, exocyclic attack of the electrophilic reagent upon the formally unsaturated rings, is in principle a mechanism analogous to that pertaining to benzenoid systems. The second mechanism invokes the metal atom itself as the initial site of electrophilic attack. Subsequent rearrangement of this intermediate, involving encocyclic attack, leads eventually to the substituted ferrocene. Attempts were made to distinguish between these two courses of reaction by conducting acylation reactions on a series of bridged ferrocenes which offered varying degrees of steric occlusion at the metal atom. Vapor phase analysis of the acyl isomers formed in the course of AlCl3 catalyzed i-butyrylation of ferrocene gave the data for the ratio of 3 to 2 substitution. (Author)

Descriptors :   *FERROCENES, *METALORGANIC COMPOUNDS, ACETYLATION, ALUMINUM COMPOUNDS, CATALYSTS, CHEMICAL ANALYSIS, CHEMICAL REACTIONS, CHLORIDES, ETHYLENES, METHYL RADICALS, STEREOCHEMISTRY, VAPORS

Distribution Statement : APPROVED FOR PUBLIC RELEASE