Cationic Acylzirconocene Complexes

Reactivity of u, (3-Unsaturated Acylzirconocene Chlorides toward Nucleophiles 

The assumed structures of the ketone—zirconocene and oxazirconacyclopentene complexes have not been established spectroscopically due to the excess of cuprate reagent present. However, as discussed in Section 5.3.2.2, (i) direct nucleophilic addition to the 

Reaction of an cc -unsaturated acylzirconocene chloride with higher-order cyanocuprate. 

Recent chemical accomplishments based on acylzirconocene chloride complexes indicate the potential utility of this reagent, not only as a nucleophilic donor of an unmasked acyl group but also as a characteristic dichotomous reagent in carbon—carbon bond-forming reactions. Although there have been many reports on the reactions of acylmetal complexes, the ready availability, stability, and notable reactivity of acylzirconocene complexes — especially acylzirconocene chloride complexes — merits their recognition as useful reagents. Further research on the reactivity of acylzirconocene species is anticipated to lead to the discovery of new synthetic applications. 

Preparation of n-heptanoylzirconocene chloride and reaction with benzaldehyde 

Pd-Catalyzed 1,2-selective reaction of n-nonanoylzirconocene chloride with cyclohexanone 

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Cationic r 2-acylzirconocenes [Cp2Zr(COR)(L)+] have been reported to show attractive reactivity [39]. A cationic r 2-acylzirconocene can be generated in quantitative yield by treating a cationic zirconocene complex [Cp2Zr(R)(L)+] (R = alkyl or alkenyl) with carbon monoxide (<23 °C, 1 atm) (Scheme 5.36). The cationic acylzirconocene complexes undergo regiose-... 

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