Synthesis of ferrocene-based amido-phosphine ligands via highly diastereoselective ortho-lithiation and their application in Pd-catalyzed asymmetric allylic alkylations
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چکیده
An efficient synthesis of novel planar chiral ferrocene-based amido-phosphine ligands was accomplished via highly diastereoselective ortho-lithiation and subsequent in situ trapping with chlorodiphenylphosphine. The palladium complexes of mono-phosphino ferrocenecarboxamide, bis-phosphino ferrocenedicarboxamide ligands, and analogues with a ferrocenophane framework were applied in the allylic alkylation of (E)-1,3-diphenyl-2-propenyl acetate. The reactions proceeded with excellent conversions and ee’s of up to 82%, the most efficient being the camphane based mono-phosphino ferrocenecarboxa-
منابع مشابه
Ferrocenyl bis-phosphine ligands bearing sulfinyl, sulfonyl or sulfenyl groups: applications in asymmetric hydrogenation and allylic alkylation reactions
A new series of chiral ferrocenyl bis-phosphine ligands have been synthesized. Elements of planar and central chirality have been incorporated into a ferrocene backbone through sulfinyl, sulfonyl and sulfenyl groups at the ortho-position to the phosphines. The effectiveness of these ligands has been demonstrated in Rh-catalyzed hydrogenations and Pd-catalyzed allylic alkylations. 2005 Elsevier ...
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