Nonconjugated diene complexes synthesis

Heck reactions on nonconjugated dienes create an electrophilic Jt-aUyl complex that is susceptible to nucleophilic attack. When the compound contains a conjugated diene, the regioselectivity becomes a very important issue, which must be considered. Cascade sequence involving a Heck reaction and a Jt-allyl reaction could be found in the formal total synthesis of Morphine by Overman [15]. Treatment of dienes with PdCOCOCFjj CPPhj) and NEtj in toluene led to formation of the backbone of Morphine in 56% yield (Scheme 7.6). 

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