Asymmetric ring-opening of oxabenzonorbornadiene with amines promoted by a chiral iridium-monophosphine catalyst
作者:Renshi Luo、Jianhua Liao、Ling Xie、Wenjun Tang、Albert S. C. Chan
DOI:10.1039/c3cc46009f
日期:——
A new iridium-monophosphine catalyst is found to be efficient for asymmetric ring-opening of benzonorbornadiene with amines, providing a series of chiral substituted dihydronaphthalenes in high yields (up to 98%) and excellent enantioselectivities (>99%).
Rhodium-Catalyzed Asymmetric Ring Opening Reactions of Oxabicyclic Alkenes: Application of Halide Effects in the Development of a General Process
作者:Mark Lautens、Keith Fagnou、Dingqiao Yang
DOI:10.1021/ja034845x
日期:2003.12.1
effects in the rhodium-catalyzed asymmetric ringopening reaction of oxabicyclicalkenes. By employing halide and protic additives, the catalyst poisoning effect of aliphatic amines is reversed allowing the amount nucleophile to react in high yield and ee. Second, by simply changing the halide ligand on the rhodium catalyst from chloride to iodide, the reactivity and enantioselectivity of reactions employing
我们已经在铑催化的氧杂双环烯烃的不对称开环反应中证明了卤化物效应。通过使用卤化物和质子添加剂,脂肪胺的催化剂中毒效应被逆转,允许一定量的亲核试剂以高产率和 ee 反应。其次,通过简单地将铑催化剂上的卤化物配体从氯化物变为碘化物,使用芳香胺、丙二酸酯或羧酸盐亲核试剂的反应的反应性和对映选择性得到显着提高。第三,通过应用卤化物效应和更强制的反应条件,反应性较低的氧杂二环 [2.2.1] 底物反应生成合成有用的对映体富集的环己烯醇产物。
Iridium-catalyzed asymmetric ring-opening reactions of oxabicyclic alkenes with secondary amine nucleophiles
Iridium-catalyzed asymmetric ring-openingreactions of oxabicyclic alkenes with various aliphatic and aromatic secondaryamines are reported for the first time. The reaction gave the corresponding trans-1,2-dihydronaphthalenol derivatives in good yields with moderate enantioselectivities in the presence of 2.5 mol % [Ir(COD)Cl](2) and 5 mol % bisphosphine ligand (S)-p-Tol-BINAP. The trans-configuration
The present invention is directed to a ring opening reaction of heteronorbomenes and other α,β-unsaturated compounds of formula (Ia) and (Ib):
with a nucleophile in the presence of a transition metal complex, characterized in that it is microwave assisted.
Rhodium-phosphorus complexes and their use in ring opening reactions
申请人:Laboratorios Del. Dr. Esteve, S.A.
公开号:EP2070904A1
公开(公告)日:2009-06-17
The present invention is directed to novel rhodium-phosphorus complexes of formula:
[Rh(PP')(solv)2]X
the process for their preparation and their use as catalysts in the ring opening reaction of heteronorbomenes and other α,β-unsaturated compounds.