A Novel One-Pot, Three-Component Synthesis of 5-Imino-2,3,5,8-tetrahydropyrazolo[1,2-a]pyridazin-1-one Derivatives
作者:Yong-Min Liang、Bo Qian、Ming-Jin Fan、Yong-Xin Xie、Lu-Yong Wu、Yun Shi
DOI:10.1055/s-0028-1088070
日期:2009.5
It was found that the zwitterionic intermediate obtained from the addition of isocyanides to dimethyl acetylenedicarboxylate could react with 1,3-dipolar compounds under mild conditions to produce 5-imino-2,3,5,8-tetrahydropyrazolo[1,2-a]pyridazin-1-one derivatives in high yields. A plausible mechanism was also discussed for this process.
Diastereoselective 1,3-Dipolar Cycloadditions of <i>N</i>,<i>N</i>′-Cyclic Azomethine Imines with Iminooxindoles for Access to Oxindole Spiro-<i>N</i>,<i>N</i>-bicyclic Heterocycles
In the presence of CuI, 1,3-dipolarcycloadditions of N,N′-cyclic azomethine imines with iminooxindoles proceeded readily and furnished novel oxindole spiro-N,N-bicyclic heterocycles in moderate to excellent chemical yields with excellent diastereoselectivities.
Brønsted Acid or Lewis Acid Catalyzed [3+3] Cycloaddition of Azomethine Imines with N-Benzyl Azomethine Ylide: A Facile Access to Bicyclic N-Heterocycles
作者:Jia Liu、Risong Na、Shuo-ning Li、Bin Yu、Hong-lian Li
DOI:10.1055/s-0035-1560506
日期:——
1,3-Dipolarcycloaddition reactions are one of the most important methods to obtain diverse heterocycles with novel skeletons. We herein report the Bronsted acid or Lewis acid catalyzed [3+3] cycloaddition of azomethine imines with nonstabilized azomethine ylide generated in situ from an N-benzyl precursor, providing a clean and facile access to diverse bicyclic N-heterocycles in moderate to good yields
Photocatalytic reductive radical–radical coupling of <i>N</i>,<i>N</i>′-cyclicazomethine imines with difluorobromo derivatives
作者:Peng-Ju Xia、Zhi-Peng Ye、Dan Song、Ji-Wei Ren、Han-Wen Wu、Jun-An Xiao、Hao-Yue Xiang、Xiao-Qing Chen、Hua Yang
DOI:10.1039/c8cc09385g
日期:——
A visible-light-induced difluoroalkylation of N,N′-cyclicazomethine imine was successfully realized through a novel photoredox radical–radical cross-coupling reaction. This developed protocol exhibits high functional group tolerance and affords a variety of difluorinated 3-pyrazolidinone scaffolds. Extensive mechanistic investigations have been undertaken, well revealing the involvement of a reductive
Highly enantioselective phosphination and hydrophosphonylation of azomethine imines: using chiral squaramide as a hydrogen bonding organocatalyst
作者:Ling-Pei Kong、Nai-Kai Li、Shao-Yun Zhang、Xiang Chen、Min Zhao、Ya-Fei Zhang、Xing-Wang Wang
DOI:10.1039/c4ob01472c
日期:——
Enantioselective phosphination and hydrophosphonylation reactions between azomethine imines and diarylphosphine oxides or dialkyl phosphites were respectively developed by the use of a chiral squaramide as the hydrogen bonding organocatalyst, which afforded two types of phosphorus containing product in high yields with good to excellent enantioselectivities.