224784-80-9Relevant academic research and scientific papers
Planar-Chiral Cyclopentadienyl-Ruthenium-Catalyzed Regio- and Enantioselective Asymmetric Allylic Alkylation of Silyl Enolates under Unusually Mild Conditions
Kanbayashi, Naoya,Yamazawa, Arisa,Takii, Koichiro,Okamura, Taka-Aki,Onitsuka, Kiyotaka
, p. 555 - 560 (2016/02/27)
We report the asymmetric allylic alkylation of allylic chlorides with silyl enolates as a carbon nucleophile using a planar-chiral cyclopentadienyl-ruthenium (Cp′Ru) catalyst. The reaction proceeds under unusually mild conditions to give the desired branched products with complete regioselectivity and high enantioselectivity, and reactive functional groups, such as aldehyde, can be tolerated. In this reaction system, Cp′Ru plays an important role in activating both silyl enolate and allylic chloride.
Ir-catalyzed regio- and enantioselective decarboxylative allylic alkylations
He, Hu,Zheng, Xiao-Jian,Li, Yi,Dai, Li-Xin,You, Shu-Li
, p. 4339 - 4341 (2008/03/12)
[Ir(COD)Cl]2/phosphoramidite ligand 1a was found to be an efficient catalytic system, for the highly regio- and enantioselective decarboxylative alkylation of γ-substltuted allyl β-ketocarboxylates, affording the branched products with up to >99/1 branched-linear ratio and 96% ee.
Halide ion effects in the rhodium-catalyzed allylic substitution reaction using copper(I) alkoxides and enolates
Evans, P. Andrew,Leahy, David K.,Slieker, Laura M.
, p. 3613 - 3618 (2007/10/03)
The transmetallation of lithium alkoxides and enolates with a copper(I) halide salt provides the requisite nucleophiles to accomplish the stereospecific rhodium-catalyzed allylic substitution. These studies demonstrate that the nature of the halide ion derived from the copper(I) salt has a profound effect on regioselectivity and enantiospecificity. This observation was attributed to the trans-effect, by virtue of an in situ modification of the catalyst by the halide ion, which leads to modulated catalytic activity and improved stereospecificity.
