| Abstract
| - The cationic exo-isopropylidene-π-allylpalladium complex [Pd(η3-CH2CMeCCMe2)(dppb)]BArF4 (1;ArF = C6H3-3,5-(CF3)2), was prepared, and its solid-state structure was determined by X-ray crystallography. The CMe2 plane of the exo-isopropylidene moiety and the η3-CH2CMeC plane are not coplanar,with a dihedral angle of 66.06°. A reaction between 1 and a stabilized nucleophile, Na[CMe(CO2Me)2],took place at the terminal methylene carbon of η3-CH2CMeC to give the corresponding allene exclusively.On the other hand, a reaction of 1 with a Grignard reagent proceeded via an initial nucleophilic attackat the Pd center to give a conjugated diene. Complex 1 showed good catalytic activity in the reactionsbetween 2-bromo-1,3-dienes and stabilized nucleophiles, and a variety of allenes were obtained in goodyields. The dynamic process of forming the alkylidene-π-allylpalladium complexes from 2-bromo-1,3-dienes and Pd(0) was also examined.
- The cationic exo-isopropylidene-π-allylpalladium complex [Pd(η3-CH2CMeCCMe2)(dppb)]BArF4 (ArF = C6H3-3,5-(CF3)2) was prepared, and its X-ray crystal structure revealed that the CMe2 plane of the exo-isopropylidene moiety and the η3-CH2CMeC plane are not coplanar, with a dihedral angle of 66.06°. The reactivity of the complex and dynamic process of its formation were examined.
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