Iridium(III)-Catalyzed Selective and Mild C-H Amidation of Cyclic <i>N</i>
-Sulfonyl Ketimines with Organic Azides
作者:Manikantha Maraswami、Gang Chen、Teck-Peng Loh
DOI:10.1002/adsc.201700785
日期:2018.2.1
A general protocol for iridium catalyzed direct C−H amidation of cyclic N-sulfonyl ketimines using sulfonyl, acyl and arylazides as nitrogen source is reported herein. The reaction takes place at roomtemperature with acyl and arylazides, while an elevated temperature needed with sulfonylazides to furnish aminated sultams in excellent yields with complete chemo and regioselectivity, thus providing
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。
Rhodium‐Catalyzed Spirocyclic Sultam Synthesis by [3+2] Annulation with Cyclic
<i>N</i>
‐Sulfonyl Ketimines and Alkynes
作者:Lin Dong、Chuan‐Hua Qu、Ji‐Rong Huang、Wei Zhang、Qian‐Ru Zhang、Jin‐Gen Deng
DOI:10.1002/chem.201303372
日期:2013.12.2
Atom‐economical addition: RhIII‐catalyzed “Grignard‐type” cyclization between cyclic N‐sulfonyl ketimines and internal alkynes has been developed to afford multifunctional spirocyclic sultam products in high yields (up to 99 %) under mild conditions (see scheme, Cp* = pentamethylcyclopentadienyl, DCE = 1,2‐dichloroethane).
RhIII-catalyzed aryl C–H vinylation for the preparation of styrenes by using vinylacetate, a commercially available and inexpensive compound, as the vinyl source was successfully realized. This method enables various aromatics including N-sulfonyl ketimines, pyridines, azoles, and amides to be vinylated in moderate to good yields.
Synthesis of Sultams and Cyclic <i>N</i>-Sulfonyl Ketimines via Iron-Catalyzed Intramolecular Aliphatic C–H Amidation
作者:Dayou Zhong、Di Wu、Yan Zhang、Zhiwu Lu、Muhammad Usman、Wei Liu、Xiuqiang Lu、Wen-Bo Liu
DOI:10.1021/acs.orglett.9b01732
日期:2019.8.2
unique role in drug discovery and synthetic chemistry. A direct synthesis of sultams by an intramolecular C(sp3)–H amidation reaction using an iron complex in situ derived from Fe(ClO4)2 and aminopyridine ligand is reported. This strategy features a readily available catalyst and tolerates a broad variety of substrates as demonstrated by 22 examples (up to 89% yield). A one-pot iron-catalyzed amidation/oxidation