80639-18-5Relevant academic research and scientific papers
Sequential catalytic isomerization and allylic substitution. Conversion of racemic branched allylic carbonates to enantioenriched allylic substitution products
Shekhar, Shashank,Trantow, Brian,Leitner, Andreas,Hartwig, John F.
, p. 11770 - 11771 (2007/10/03)
A catalytic protocol for the conversion of readily accessible racemic, branched aromatic allylic esters to branched allylic amines, ethers, and alkyls has been developed. Palladium-catalyzed isomerization of branched allylic esters to terminal allylic esters, followed by sequential iridium-catalyzed allylic substitution, gave the branched allylic products in good yield with high regioisomeric and enantiomeric selectivity. Both electron-rich and electron-poor branched allylic esters gave products in >90% ee. High enantiomeric excesses were also observed for the products from the reactions of 2-thienyl acetates and dienyl carbonates. Copyright
Example of thermodynamic control in palladium-catalyzed allylic alkylation. evidence for palladium-assisted allylic C-C bond cleavage
Nilsson, Ylva I.M.,Andersson, Pher G.,B?ckvall, Jan-E.
, p. 6609 - 6613 (2007/10/02)
Pd(0)-catalyzed reactions of a number of dienyl acetates with dialkyl malonates show that the regiochemistry of the reaction is very dependent on the reaction conditions. At low temperature and short reaction times the reaction is under kinetic control, but at elevated temperature and longer reaction times the reaction is under thermodynamic control. Under the latter conditions it was demonstrated that the kinetic allylic malonate rearranged to its thermodynamically more stable regioisomer in the presence of the Pd(0) catalyst. The results strongly support the cleavage of an allylic C-C bond by Pd(0), and thus the dialkyl malonate anion has acted as a leaving group.
