Pd II -Catalyzed Allylic Rearrangement

Overman and co-workers carried out extensive studies on Pd(II)-catalyzed asymmetric allylic rearrangement of allylic imidates to form enantioenriched allylic amides. They achieved 97 % ee as the best result by the reaction of the allylic imidate 612 using the cyclopalladated ferrocenyl oxazoline 613 having elements of planar chirality as a catalyst precursor, and discussed the mechanism of the reaction [220]. 

Gais and Bdhme reported that Pd(0)-catalyzed enantioselective 0,5-rearrangement of the racemic O-allylic thiocarbamate 614 using Pd(0) and Trost L-1 as a chiral ligand provided the 5-allylic thiocarbamate 615 in 92% yield with 91 % 

Reactive methylene-7r-allylpalladiums 618 are generated from esters of 2,3-aUca-dienyl alcohols 617, and react with nucleophiles to afford either 1,2-dienes 619 or 1,3-dienes 620 regioselectively depending on the nature of allyl leaving groups and nucleophiles. 

2-dienes (allenes) 622 and 623 were obtained by the reaction of soft carbon nucleophiles such as malonate [222]. On the other hand, reaction of the phosphate 624 with Grignard reagent provided the 1,3-diene 625 [223]. Carbony-lation of the carbonate 626 proceeded smoothly under mild conditions (rt, 1 atm) and 3-alkyl-l,3-butadiene-2-carboxylate 627 was obtained in high yield [224]. The 2,3-dienylamine 628 was carbonylated under harsh conditions to provide the a-vinylacrylamide 629 in the presence of DPPP and TsOH [225]. 

Murahashi carried out the reaction of the phosphate 630 with the aminomalonate 

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