Highly Enantioselective Pd-Catalyzed Asymmetric Hydrogenation of Activated Imines
作者:You-Qing Wang、Sheng-Mei Lu、Yong-Gui Zhou
DOI:10.1021/jo0700878
日期:2007.5.1
complexes are highly effective catalysts for asymmetrichydrogenation of activated imines in trifluoroethanol. The asymmetrichydrogenation of N-diphenylphosphinyl ketimines 3 with Pd(CF3CO2)/(S)-SegPhos indicated 87−99% ee, and N-tosylimines 5 could gave 88−97% ee with Pd(CF3CO2)/(S)-SynPhos as a catalyst. CyclicN-sulfonylimines 7 and 11 were hydrogenated to afford the useful chiral sultam derivatives in
Pd /双膦配合物是用于活化的亚胺在三氟乙醇中不对称氢化的高效催化剂。Pd(CF 3 CO 2)/(S)-SegPhos对N-二苯基亚膦酰基酮亚胺3的不对称氢化表明ee为87-99%,N- tosylimines 5与Pd(CF 3 CO 2)可以得到88-97%ee /(S)-SynPhos作为催化剂。环状N-磺酰亚胺7和11 进行氢化,以79-93%ee的比重得到有用的手性舒马坦衍生物,这是重要的有机合成中间体和农业和医药制剂的结构单元。
Enantioselective Intramolecular Benzylic CH Bond Amination: Efficient Synthesis of Optically Active Benzosultams
'Salen' along: The iridium(III)–salen complex 1 efficiently catalyzes the title reaction of 2‐ethylbenzenesulfonyl azides to give five‐membered sultams with high enantioselectivity. Other 2‐alkyl‐substitued substrates lead to five‐ and six‐membered sultams with high enantioselectivity; the regioselectivity depends upon the substrate and the catalyst used. EDG=electron‐donating group.
Practical Synthesis of Chiral Sultam Auxiliaries: 3-Substituted- 1,2-benzisothiazoline 1,1-Dioxides
作者:Kyo Han Ahn、Cheol Ham、Seung-Kee Kim、Chang-Woo Cho
DOI:10.1021/jo970917p
日期:1997.10.1
A Chiral Rhodium Complex for Rapid Asymmetric Transfer Hydrogenation of Imines with High Enantioselectivity
作者:Jianmin Mao、David C. Baker
DOI:10.1021/ol990098q
日期:1999.9.1
[GRAPHICS]A chiral rhodium complex, (R)-Cp*RhCl[(1S,2S)-p-TsNCH(C6H5)CH(C6H5)NH2] (1a, (S,S)-Cp*RhCITsDPEN), generated from [Cp*RhCl2](2) and (1S,2S) N-p-toluenesulfonyl-1,2-diphenylethylenediamine [(S,S) TsDPEN], and its enantiomer 1b were found to provide superior catalysts for the rapid, high yielding, asymmetric transfer hydrogenation of some heterocyclic imines, using an HCO2H-Et3N azeotrope as the hydrogen source.