Stereodefined Homopropargyl Amines by Tandem Nucleophilic Addition/Fragmentation of Dihydropyridone Triflates
摘要:
Dihydropyridone (DHPD) triflates undergo nucleophile-triggered fragmentation to provide homopropargyl amine derivatives, the stereochemistry of which is defined by starting from readily available beta-amino esters.
Stereodefined Homopropargyl Amines by Tandem Nucleophilic Addition/Fragmentation of Dihydropyridone Triflates
摘要:
Dihydropyridone (DHPD) triflates undergo nucleophile-triggered fragmentation to provide homopropargyl amine derivatives, the stereochemistry of which is defined by starting from readily available beta-amino esters.
Formation of 2,3-dihydro-4(1H)-quinolones and related compounds via Fries-type acid-catalysed rearrangement of 1-arylazetidin-2-ones
作者:Shinto Kano、Tsutomu Ebata、Shiroshi Shibuya
DOI:10.1039/p19800002105
日期:——
corresponding 2,3-dihydro-4(1H)-quinolones via acyl migration and N–CO fission. In the case of 1-(3-substituted phenyl)azetidin-2-ones, two positional isomeric products, 5- and 7-substituted 2,3-dihydro-4(1H)-quinolones were obtained. 4-Methyl-, 4-ethoxycarbonyl-, and 4-piperidin-2yl-1-arylazetidin-2-ones and their analogues were also converted into the corresponding 2-substituted 2,3dihydro-4(1H)-quinolones
The Merger of Aryl Radical-Mediated Halogen-Atom Transfer (XAT) and Copper Catalysis for the Modular Cross-Coupling-Type Functionalization of Alkyl Iodides
作者:Lewis Caiger、Huaibo Zhao、Timothée Constantin、James J. Douglas、Daniele Leonori
DOI:10.1021/acscatal.3c00571
日期:——
cross-couple unactivated secondary alkyl iodides with various N-, O-, and C-based nucleophiles. This strategy harnesses the ability of photoredox-generated phenyl radicals to mediate halogen-atom transfer (XAT) and convert alkyl iodides into the corresponding radicals. These species engage in a second catalytic cycle, mediated by copper, which enables C–N/O/C bond formation with the various nucleophiles
在这里,我们报告了一种工具箱策略,用于将未活化的仲烷基碘与各种基于 N、O 和 C 的亲核试剂交叉偶联。该策略利用光氧化还原产生的苯基自由基介导卤素原子转移 (XAT) 并将烷基碘转化为相应自由基的能力。这些物质参与由铜介导的第二个催化循环,从而能够与各种亲核试剂形成 C-N/O/C 键。
Chemo- and Diastereoselective Reduction of .beta.-Enamino Esters: A Convenient Synthesis of Both cis- and trans-.gamma.-Amino Alcohols and .beta.-Amino Esters
Convenient procedures for the chemo- and diastereoselective reduction of beta-enamino esters 1 are described. Both cis- and trans-gamma-amino alcohols 2 or beta-amino esters 3 can be prepared by reduction of beta-enamino esters 1, readily available starting materials, with the use of inexpensive reagents Nali-PrOH or NaHbB(OAc)(3)/AcOH, respectively, and the appropriate reduction conditions. The mechanisms and diastereoselectivities for the reductions are discussed. The relative configurations and conformations of the diastereoisomeric gamma-amino alcohols 2 and beta-amino esters 3 obtained are established by H-1 and C-13 NMR study and unequivocally set by their cyclic derivatives tetrahydro-1,3-oxazines 4.
KANO SHINZO; EBATA TSUTOMU; SHIBUYA SHIROSHI, J. CHEM. SOC. PERKIN TRANS., PART 1, 1980, NO 10, 2105-2111