Results 51 to 60 of about 25,799 (236)
Regio- and stereoselective methods for the synthesis of 6′-trifluoro(trichloro)methyl substituted spiro[acenaphthylene-1,11′-chromeno[3,4-a](thia)pyrrolizidin]-2-ones and spiro[acenaphthylene-1,12′-chromeno[3,4-a]indolizidin]-2-ones have been developed ...
Igor B. Kutyashev +6 more
doaj +1 more source
Decarboxylative 1,3-dipolar cycloaddition of amino acids for the synthesis of heterocyclic compounds
The [3 + 2] cycloadditions of stabilized azomethine ylides (AMYs) derived from amino esters are well-established. However, the reactions of semi-stabilized AMYs generated from decarboxylative condensation of α-amino acids with arylaldehydes are much less
Xiaofeng Zhang, Xiaoming Ma, Wei Zhang
doaj +1 more source
A short and efficient multicomponent sequence for synthesizing fused novel polyheterocyclic chromeno spiro-pyrrolidine oxindoles via 1,3-dipolar cycloaddition reaction mediated by reactive azomethine ylides catalyzed by the Graphene Oxide (GO) is ...
Vipin Singh +2 more
doaj +1 more source
A series of novel dispirooxindoles have been synthesized through three-component 1,3-dipolar cycloaddition of azomethine ylides generated in situ by the decarboxylative condensation of isatin and an α-amino acid with the dipolarophile 5-benzylidene-1,3 ...
Yucheng Wang +9 more
doaj +1 more source
The enantioselective 1,3-dipolar cycloaddition between imino esters and (Z)-nitroalkenes bearing a masked amino group in the β-position was studied using several chiral ligands and silver salts.
Eduardo García-Mingüens +5 more
doaj +1 more source
<i>N</i>-Oxide Insertion into LDA Dimeric Aggregates for Azomethine Ylide Formation: Explicit Solvation in Quantum Mechanical Treatment of Polarized Intermediates. [PDF]
Neal MJ +10 more
europepmc +2 more sources
Kinetic resolution by copper hydride catalyzed reduction of 2H‐azirines secured optically enriched N‐H aziridine‐2‐carboxylates with excellent diastereoselectivity (>20:1) and good enantioselectivity (up to 94% ee). DFT calculations and non‐covalent interaction analysis established the reaction pathway and revealed two key non‐covalent interactions ...
Yinuo Zheng +3 more
wiley +2 more sources
Summary: Development of a general catalytic and highly efficient method utilizing readily available precursors for the regio- and stereoselective construction of bioactive natural-product-inspired spiro architectures remains a formidable challenge in ...
Chong Shen +5 more
doaj +1 more source
A new series of di-spirooxindole analogs, engrafted with oxindole and cyclohexanone moieties, were synthesized. Initially, azomethine ylides were generated via reaction of the substituted isatins 3a–f (isatin, 3a, 6-chloroisatin, 3b, 5-fluoroisatin, 3c ...
Abdullah Mohammed Al-Majid +7 more
doaj +1 more source
The regioselective three-component condensation of azomethine ylides derived from isatins and α-amino acids with acrylamides or aroylacrylic acids as dipolarophiles has been realized through a one-pot 1,3-dipolar cycloaddition protocol.
Tatyana L. Pavlovskaya +6 more
doaj +1 more source

