Novel diphosphines, their complexes with transisition metals and their use in asymmetric synthesis
申请人:——
公开号:US20040260101A1
公开(公告)日:2004-12-23
The invention relates to novel diphosphines, in optically pure or racemic form, of formula (I):
1
in which:
R
1
and R
2
are a (C
5
-C
7
)cycloalkyl group, an optionally substituted phenyl group or a 5-membered heteroaryl group; and
A is (CH
2
—CH
2
) or CF
2
.
The invention further relates to the use of a compound of formula (I) as a ligand for the preparation of a metal complex useful as a chiral catalyst in asymmetric catalysis, and to the chiral metal catalysts comprising at least one ligand of formula (I).
A convergent and flexible stereoselective synthesis of one isomer of the C44-C65 fragment of mirabalin is described. The key steps include organocatalytic aldolization, ruthenium-catalyzed asymmetric hydrogenation, amide formation, Marshall stereoselective allenylation, and the Nozaki-Hiyama-Kishi reaction.
Progress toward the total synthesis of mirabalin isomers
Key fragments of the cytotoxic marine macrolide mirabalin have been synthesized, by using a flexible strategy based on asymmetric reductions to control the hydroxyand carbamate-bearing stereocenters. In particular, ruthenium or rhodium-mediated asymmetric hydrogenation and transfer hydrogenation were used in combination with a dynamic kinetic resolution to control two contiguous stereocenters in a
A Sphingolipid Fatty Acid Constituent Made by Alkyne
<i>trans</i>
‐Hydrogenation: Total Synthesis of Symbioramide
作者:Karin Radkowski、Alois Fürstner
DOI:10.1002/adsc.202200540
日期:2022.10.4
acid ((−)-2) is reported, which is the fatty acid constituent of numerous sphingolipids of biological significance. Key to success was the chemoselective trans-hydrogenation of a functionalized propargylic alcohol precursor with [Cp*RuCl]4 as the catalyst, followed by lipase-catalyzed resolution of the racemic product. (−)-2 then served the shortest totalsynthesis of the marinenaturalproduct symbioramide