Abstract:
:Individual diastereomeric phosphoramidites and mixtures of diastereomeric phosphoramidites were evaluated in the iridium-catalyzed amination of allylic carbonates. The original process was conducted with a phosphoramidite ligand containing a resolved 2,2-dihydroxy-1,1-binaphthyl (BINOL) group and a diastereomerically and enantiomerically pure bis(phenethyl)amino group. Evaluation of the structure of the active catalyst and relative rates for reactions in the presence of catalysts containing diastereomeric ligands led to the identification of a phosphoramidite that provided the amination product with enantiomeric excess similar to the original, more structurally and stereochemically complex ligand and that contains a racemic BINOLate and an N-benzylphenethylamino group on phosphorus.
journal_name
Proc Natl Acad Sci U S Aauthors
Leitner A,Shu C,Hartwig JFdoi
10.1073/pnas.0307967101keywords:
subject
Has Abstractpub_date
2004-04-20 00:00:00pages
5830-3issue
16eissn
0027-8424issn
1091-6490pii
0307967101journal_volume
101pub_type
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