Carbonylation carbopalladation trapping

The aminopalladation and subsequent carbonylation proceed smoothly. The aminopalladation of one of the double bonds of allene 129 generates 130, and CO insertion affords the ester 131 [96]. The carbopalladation of the optically active N-vinyl carbamate 132 with malonate afforded 133. Then CO insertion and trapping with vinylstannane produced the ketone 134 with 95% de, which was converted to 135 [97]. 

Alkenes that can provide hydrogen atoms /3 and syn to Pd, such as monosubstituted alkenes, may not be used in the cyclic carbopalladation-carbonylative trapping process, as the reaction is dominated by the cyclic Heck reaction. The difference between this process and the Type II Ac—Pd process (Sect. VI.4.1.1) may be attributable to a chelation effect in the latter preventing otherwise competitive dehydropalladation. 

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