Nucleophilic Addition to Arene–Metal Complexes
1991; Elsevier BV; Linguagem: Inglês
10.1016/b978-0-08-052349-1.00102-5
Autores Tópico(s)Asymmetric Hydrogenation and Catalysis
ResumoThis chapter covers reactions in which coordination of a transition metal to the π-system of an arene ring activates the ring toward addition of nucleophiles, to give η5-cyclohexadienyl-metal complexes (1; Scheme 1). If an electronegative atom is present in the ipso position, elimination of that atom (X in 1) leads to nucleophilic aromatic substitution (path a). Reaction of the intermediate with an electrophile (E+) can give disubstituted 1,3-cyclohexadiene derivatives (path b). If a hydrogen occupies the ipso position, oxidation of the intermediate gives formal nucleophilic substitution for hydrogen (path c). These processes have been uncovered and developed relatively recently and have significant potential in synthesis methodology. General reviews have appeared1–3 as well as others with an emphasis on [(η6−-arene)Cr(CO)3] complexes,4–6 on [(η6-arene)FeCp]+ (Cp = η5-cyclopentadienyl) complexes7,8 and on [(η6-arene)Mn(CO)3]+ complexes,9 but none with emphasis on synthesis scope and limitations. The purpose of this chapter is to illustrate the established methodology and to point to future possibilities; mechanistic questions are included when helpful in understanding the scope and limitations. The coverage is representative and not comprehensive.
Referência(s)