Fine‐Tuning the Bicyclo[3.3.1]nona‐2,6‐diene Ligands: Second Generation 4,8‐Substituted Dienes for Rh‐Catalyzed Asymmetric 1,4‐Addition Reactions
作者:Vidmantas Bieliūnas、Sigitas Stončius
DOI:10.1002/cctc.202100638
日期:2021.9.7
C2-symmetric 4,8-endo,endo-bis(alkoxy) bicyclo[3.3.1]nona-2,6-diene ligands possessing additional 4,8-exo,exo substituents is reported. The 4,8-exo,exo groups provide a further element for fine-tuning of the ligand structure by enforcing conformational rigidity of the 4,8-endo,endo side chains. Such tetrasubstituted bicyclo[3.3.1]nona-2,6-dienes were employed as steering ligands in the rhodium-catalyzed arylation
New chiral phosphorus–olefin hybrid ligands derived from the rigid “privileged” l‐proline have been conveniently prepared and applied in the rhodium‐catalyzed asymmetric arylation of electron‐deficient olefins with arylboronic acids at room temperature; this reaction provides the desired products in excellent yields and high enantioselectivities. The origin of observed stereoselectivity has been investigated
Monodentate Non-<i>C</i><sub>2</sub>-symmetric Chiral <i>N</i>-Heterocyclic Carbene Complexes for Enantioselective Synthesis. Cu-Catalyzed Conjugate Additions of Aryl- and Alkenylsilylfluorides to Cyclic Enones
作者:Kang-sang Lee、Amir H. Hoveyda
DOI:10.1021/jo900589x
日期:2009.6.19
alkenyltetrafluorosilicate. Reactions proceed in the presence of 1.5 equiv of the aryl- or alkenylsilane reagents and 1.5 equiv of tris(dimethylamino)sulfonium difluorotrimethylsilicate (TASF). Desired products are isolated in 63−97% yield and 73.5:26.5−98.5:1.5 enantiomeric ratio (47%−97% ee). A major focus of the present studies is the design, evaluation, and development of new chiral imidazolinium salts and their
A New Type of Chiral Cyclic Sulfinamide-Olefin Ligands for Rhodium-Catalyzed Asymmetric Addition
作者:Quan Wen、Li Zhang、Jing Xiong、Qingle Zeng
DOI:10.1002/ejoc.201601206
日期:2016.11
A new type of chiral cyclic sulfinamide–olefin ligands, N-allylic 2,3-dihydro-1,2-benzoisothiazole 1-oxides, with 2,3-dihydro-1,2-benzoisothiazole 1-oxide as a unique chiral skeleton, is developed for the highly enantioselective rhodium-catalyzed asymmetric 1,4-addition of α,β-unsaturated cyclic carbonyl compounds and the 1,2-addition of benzil. Both enantiomers of the chiral cyclic sulfinamide–olefin
Chiral N-aryl tert-butanesulfinamide-olefin ligands for rhodium-catalyzed asymmetric 1,4-addition of aryl boronic acids to cyclic enones
作者:Shuai Yuan、Qingle Zeng、Jiajun Wang、Lihong Zhou
DOI:10.24820/ark.5550190.p009.977
日期:——
Chiral N-aryl sulfinamide-olefins which are readily synthesized via C-N coupling and nucleophilic substitution have been used as chiralligands, which demonstrate moderate to excellent asymmetric catalytic performance in the rhodium-catalyzedasymmetric1,4-addition of arylboronicacids to cyclic enones. The chiralligands are readily synthesized via C-N coupling reaction and nucleophilic substitution