Crotylpalladium chloride

Bidentate palladium complexes of 5 were formed upon the addition of PdCl2, as shown by P-NMR spectroscopy, and even for the largest dendrimers steric interactions between the dendritic branches did not prevent the facile formation of the bidentate complex. Crotylpalladium chloride complexes were prepared in situ from these dendrimers and used as catalysts for allylic alkylation reactions. The regio-selectivity for the branched product for the alkylation of 3-phenylallyl acetate with diethyl sodio-2-methylmalonate increased when the higher-generation dendrimers were used, albeit at the cost of a lower activity. 

Bis(7r-crotylpalladium chloride) was prepared by the reaction of palladium chloride solution in 50% acetic acid with crotyl chloride at +30°C. (19). 

The spectrum of crotylpalladium chloride in CDC13 solution containing dimethyl sulfoxide (Figure 6) displays a transition to the dynamic structure at room temperature this transition appears to be completed at 110°C. 

The results on Pd complexes as catalyst for the 1 1 codimerization are very limited at this time (85-87). Schneider (85, 86) found that palladous chloride in conjunction with dibutylaluminum chloride catalyzes the formation of exclusively trans-1,4-hexadiene as the 1 1 codimerization product of ethylene and butadiene. A vyn-7r-crotylpalladium complex was postulated as the key intermediate. The criterion for selectivity toward... 

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