A new class of modular P,N‐ligandlibrary has been synthesized and screened in the Pd‐catalyzed allylicsubstitutionreactions of several substrate types. These series of ligands can be prepared efficiently from easily accessible hydroxyl–oxazole/thiazole derivatives. Their modular nature enables the bridge length, the substituents at the heterocyclic ring and in the alkyl backbone chain, the configuration
The present invention is directed to compounds represented by the following structural formula, Formula I:
wherein:
(a) X is selected from the group consisting of a single bond, O, S, S(O)
2
and N;
(b) U is an aliphatic linker;
(c) Y is selected from the group consisting of C, O, S, NH and a single bond;
(d) E is C(R3)(R4)A or A and wherein
(i) A is selected from the group consisting of carboxyl, tetrazole, C
1
-C
6
alkylnitrile, carboxamide, sulfonamide and acylsulfonamide;
(e) B is selected from the group consisting of S, O, C, and N;
(f) Z is selected from the group consisting of N and C; with the proviso that when B is C then Z is N.
US7384965B2
申请人:——
公开号:US7384965B2
公开(公告)日:2008-06-10
US7598266B2
申请人:——
公开号:US7598266B2
公开(公告)日:2009-10-06
Asymmetric Hydrogenation of Trisubstituted Olefins with Iridium−Phosphine Thiazole Complexes: A Further Investigation of the Ligand Structure
作者:Christian Hedberg、Klas Källström、Peter Brandt、Lars Kristian Hansen、Pher G. Andersson
DOI:10.1021/ja057178b
日期:2006.3.1
prepared and successfully applied as ligands in the homogeneous iridium-catalyzed asymmetrichydrogenation of aryl alkenes and aryl alkene esters. The ligands are designed to be highlymodular and have one common chiral intermediate, from which diversity can be introduced at a late stage in the synthetic pathway. It was found that a six-member-ring backbone of the rigid ligand structure was preferred over