Palladium acetate mesylate

Treatment of the diamide 77 with dibutyltin dichloride affords the 2,2-bis(2-[4(/ ),5(5)-diphenyl-1,3-oxazolinyl])propane 78, while successive reaction of 77 with mesyl chloride and aqueous ethanolic sodium hydroxide yields the diastereomer 79 <96TI3649>. The (+)- and (-)-forms of the chiral oxazoline 80 were used as ligands for palladium catalysed allylic amination reactions thus the acetate 81 and benzylamine gave the optically active amine 82 in excellent enantiomeric excess <97JOC55Q8>. The enantioselective catalytic alkylation of aldehydes RCHO (R = n-heptyl, Ph, cyclohexyl or PhCH=CH) with allyluibutyltin in the presence of chiral bis(oxazolinyl)zinc complexes, c.g., 83, leads to alcohols 84 in 40 6% enantiomeric excess <97TL145>. 

Aryl chlorides are important starting materials in palladium-catalyzed coupling reactions [7]. Compared with the corresponding aryl iodides or aryl bromides, the advantages of aryl chlorides are obviously that they are inexpensive, easy to prepare, stable, etc. The same is true if we compare aryl tosylates or aryl mesylates with their aryl triflates analogs. Even though aryl chlorides, aryl mesylates and aryl acetates have been studied and have succeeded in cross-coupling reactions, their... 

Interestingly, trimethylsilylmethyl-substimted allyl complexes of palladium 11.105 and molybdenum can be obtained from the reaction of the corresponding mesylate 11.104 (a much better leaving group than acetate) in the absence of any silophilic nucleophile, while some other metals, including iridium, did give a TMM complex 11.106 (Scheme 11.35). ... 

The resulting intermediate (—)-107 underwent cyclization to the piperidine (—)-108 after mesylation and base treatment. Acidic hydrolysis of the acetal and reduction of the resulting cycHc hemiacetal with sodium borohydride produced the triol (—)-109, the vicinal diol component of which was cleaved with periodate before reductive amination with hydrogen and palladium on carbon completed the synthesis of (+)-88. 

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