ChemInform Abstract: Catalyst-Free, Aqueous and Highly Diastereoselective Synthesis of New 5-Substituted 1H-Tetrazoles via a Multicomponent Domino Knoevenagel Condensation/1,3-Dipolar Cycloaddition Reaction.

ChemInform ◽  
2012 ◽  
Vol 43 (27) ◽  
pp. no-no
Author(s):  
Zeinab Noroozi Tisseh ◽  
Minoo Dabiri ◽  
Mohsen Nobahar ◽  
Hamid Reza Khavasi ◽  
Ayoob Bazgir
Keyword(s):  
Knoevenagel Condensation ◽  
Cycloaddition Reaction ◽  
Dipolar Cycloaddition ◽  
Diastereoselective Synthesis ◽  
Catalyst Free

Lewis Acid Catalyzed Regio- and Diastereoselective Synthesis of Spiroisoxazolines via One-Pot Sequential Knoevenagel Condensation/1,3-Dipolar Cycloaddition Reaction

Synthesis ◽  
2019 ◽  
Vol 51 (07) ◽  
pp. 1669-1679 ◽  
Author(s):  
Ayoob Bazgir ◽  
Hossein Yazdani
Keyword(s):  
Knoevenagel Condensation ◽  
Cycloaddition Reaction ◽  
Dipolar Cycloaddition ◽  
Coupling Reactions ◽  
Diastereoselective Synthesis ◽  
Reaction Conditions ◽  
One Pot ◽  
Ch Acids ◽  
Acid Catalyzed ◽  
Metal Catalyzed

A ZnCl2-catalyzed regio- and diastereoselective one-pot sequential Knoevenagel condensation/1,3-dipolar cycloaddition reaction of CH acids (oxindole, 1,3-indandione, and 3H-pyrazol-3-one), aldehydes, and dibromoformaldoxime has been established. The method allows the synthesis of diversely functionalized spiroisoxazolines in good isolated yields under mild reaction conditions. Moreover, the preparation of spiroindene-isoxazole-1,3-diones containing benzoimidazole or benzothiazole moieties as new ligands for the metal-catalyzed coupling reactions and C–H activation is demonstrated.

Rapid Access to Novel 1,2,3-Triazolo-Heterocyclic Scaffolds via Tandem Knoevenagel Condensation/Azide–Alkyne 1,3-Dipolar Cycloaddition Reaction in One Pot

2014 ◽  
Vol 16 (9) ◽  
pp. 466-477 ◽  
Author(s):  
Ram Awatar Maurya ◽  
Praveen Reddy Adiyala ◽  
D. Chandrasekhar ◽  
Chada Narsimha Reddy ◽  
Jeevak Sopanrao Kapure ◽  
...  
Keyword(s):  
Knoevenagel Condensation ◽  
Cycloaddition Reaction ◽  
Dipolar Cycloaddition ◽  
One Pot ◽  
Rapid Access

Beyond the Alternatives that Switch the Mechanism of the 1,3-Dipolar CyCloadditions from Concerted to Stepwise or Vice Versa: A Literature Review

2016 ◽  
Vol 41 (4) ◽  
pp. 331-344 ◽  
Author(s):  
Seyyed Amir Siadati
Keyword(s):  
Organic Chemistry ◽  
Literature Review ◽  
Cycloaddition Reaction ◽  
Dipolar Cycloaddition ◽  
Stepwise Mechanism ◽  
Dipolar Cycloadditions ◽  
Catalyst Free ◽  
Number Of Factors ◽  
Reaction Channels ◽  
The 1960S

For several decades, the concerted or stepwise character of the mechanism of the 1,3-dipolar cycloaddition reaction has been one of the most debated issues in the field of organic chemistry. The significance of this problem is due to the fact that in a catalyst-free 1,3-dipolar cycloaddition, when the mechanism switches from concerted to stepwise, the stereospecificity is lost and thus unwanted stereoisomers may emerge. The first proposals about the mechanism of the 1,3-dipolar reaction were due to Huisgen (concerted model) and subsequently by Firestone (two-step diradical channel) in the 1960s. After a decade of debate, most researchers accepted the concerted model for the reaction, but during these years, researchers reported some examples of the stepwise mechanism for catalyst-free 1,3-dipolar cycloadditions. This review attempts to find a number of factors that could influence the reaction channels and switch the mechanism from concerted to stepwise, or vice versa.

scholarly journals Diastereoselective Synthesis of Spiro[Pyrrolo[2,1-B][1,3] Benzothiazole-3,5′-[1,3]Thiazolo[3,2-B][1,2,4]Triazol]-6′-Ones via Cycloaddition Reaction of Benzothiazolium Salts

2018 ◽  
Vol 42 (7) ◽  
pp. 371-373 ◽  
Author(s):  
Qing Zeng ◽  
Demin Ren ◽  
Yulin Huang ◽  
Xinliang Fu ◽  
Xiaofang Li
Keyword(s):  
Cycloaddition Reaction ◽  
Crystallographic Analysis ◽  
Azomethine Ylide ◽  
Dipolar Cycloaddition ◽  
Diastereoselective Synthesis ◽  
X Ray

The 1,3-dipolar cycloaddition reaction of (Z)-5-arylidene[1,3]thiazolo[3,2-b][1,2,4]triazol-6(5H)-one and azomethine ylide, which was generated in situ by the reaction of N-4-methoxyphenacylbenzothiazolium bromides and triethylamine, afforded novel 2-(aryl)-1-(4-methoxybenzoyl)-1,2-dihydrospiro[pyrrolo[2,1-b][1,3]benzothiazole-3,5′-[1,3]thiazolo[3,2-b][1,2,4]triazol]-6′-ones in moderate yields. The structures of all the products were characterised thoroughly by NMR, IR and HRMS spectroscopy together with X-ray crystallographic analysis.

scholarly journals Heterogeneous graphene oxide as recyclable catalyst for azomethine ylide mediated 1,3 dipolar cycloaddition reaction in aqueous medium

RSC Advances ◽  
2018 ◽  
Vol 8 (62) ◽  
pp. 35587-35593 ◽  
Author(s):  
Marri Sameer Reddy ◽  
Nandigama Satish Kumar ◽  
L. Raju Chowhan
Keyword(s):  
Graphene Oxide ◽  
Aqueous Medium ◽  
Cycloaddition Reaction ◽  
Recyclable Catalyst ◽  
Azomethine Ylide ◽  
Dipolar Cycloaddition ◽  
Diastereoselective Synthesis ◽  
Good Substrate

Graphene oxide (GO) catalyzed regio and diastereoselective synthesis of spiro-indenoquinoxaline pyrrolizidines and spiro-oxindoles pyrrolizidines is described with good substrate scope and yield using azomethine ylide under aq. EtOH condition at RT.

Regio- and Diastereoselective Synthesis of Novel Polycyclic Pyrrolo[2,1-a]isoquinolines Bearing Indeno[1,2-b]quinoxaline Moieties by a Three-Component [3+2]-Cycloaddition Reaction

Synlett ◽  
2019 ◽  
Vol 31 (03) ◽  
pp. 267-271 ◽  
Author(s):  
Firouz Matloubi Moghaddam ◽  
Atiyeh Moafi ◽  
Behzad Jafari ◽  
Alexander Vilinger ◽  
Peter Langer
Keyword(s):  
Cycloaddition Reaction ◽  
Reaction Times ◽  
Dipolar Cycloaddition ◽  
Diastereoselective Synthesis ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
One Pot ◽  
Three Component Reaction ◽  
Relative Stereochemistry ◽  
High Yields

A regio- and diastereoselective synthesis of 2,3-dihydro-10b′H-spiro[indeno[1,2-b]quinoxaline-11,1′-pyrrolo[2,1-a]isoquinoline]-2′,3′-diylbis(phenylmethanone) derivatives containing four contiguous chiral stereocenters was achieved through 1,3-dipolar cycloaddition of isoquinolinium N-ylides in a one-pot three-component reaction. The desired products were obtained in short reaction times and in moderate to high yields (up to 92%) under relatively mild reaction conditions. The structure and relative stereochemistry of the desired product was confirmed by X-ray diffraction analysis.

scholarly journals Regio- and Stereoselectivity in the 1,3-Dipolar Cycloaddition Reactions of Isoquinolinium Ylides with Cyclopenta[a]acenaphthylen-8-ones

Synlett ◽  
2020 ◽  
Vol 31 (17) ◽  
pp. 1691-1695
Author(s):  
Issa Yavari ◽  
Parisa Ravaghi ◽  
Maryam Safaei ◽  
Jasmine Kayanian
Keyword(s):  
Dft Calculations ◽  
Cycloaddition Reaction ◽  
Crystallographic Analysis ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
Diastereoselective Synthesis ◽  
X Ray

AbstractA convenient regio- and diastereoselective synthesis of functionalized 5a,5b-dihydro-5H,13H-naphtho[1′′,8′′:4′,5′,6′]pentaleno[1′:3,4]pyrrolo[2,1-a]isoquinolin-5-ones via 1,3-dipolar cycloaddition reaction of 8H-cyclopenta[a]acenaphthylen-8-ones with carbonyl-stabilized isoquinolinium N-ylides, is described. Based on DFT calculations at b3lyp/6-311+g(d,p) level of theory, a nonconcerted mechanism is proposed to explain the regioselectivity of this reaction. The structure of a typical product was confirmed by X-ray crystallographic analysis.

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