Transformations Involving CO Insertion Into a Pd-Heteroatom Bond

Transformations Involving CO Insertion Into a Pd-Heteroatom Bond 

Several transformations involving CO insertion into a Pd-heteroatom bond have been developed that lead to incorporation of two molecules of CO into the heterocyclic product. This approach to heterocycle synthesis is exemplified by a synthesis of dihydroindolones reported by Gabriele [101]. As shown below, treatment of ortho-alkynyl aniline 157 with a Pd catalyst under CO in methanol afforded 158 in 50% yield (Eq. (1.62)). A similar strategy has been employed for the conversion of alkene 159 to pyrrolidinone 160 (Eq. (1.63)) [102]. 

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