학술논문
Avoiding the classical resolution during the synthesis of MeO-BIPHEP and 3,3′-disubstituted derivatives
Document Type
Article
Author
Source
Subject
*CHROMATOGRAPHIC analysis
*HYDROGENATION
*PALLADIUM
*ORGANIC chemistry
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Language
ISSN
0040-4039
Abstract
Abstract: The Ullmann coupling of 1 (R=H) gives a 2:1 mixture of diastereomers 2 (R=H) in 81% yield that are easily separated by silica gel chromatography. This procedure avoids the generally cumbersome and sometimes difficult resolution step with DBTA. Similar Ullmann couplings and separation of the corresponding diastereomers are employed with other derivatives of 1 (R=OtBu, iPr, Ph, and mesityl) ultimately affording a new series of 3,3′-disubsituted-MeO-BIPHEP derivatives. The use of these new derivatives in palladium-catalyzed asymmetric Heck reaction, Pd-catalyzed polyene cyclizations and rhodium-catalyzed hydrogenations is also reported. [Copyright &y& Elsevier]