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.

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 Synthesis of Dispiro[Indeno[1,2-b]Quinoxaline-11,3′-Pyrrolizine-2′,2″-[1,3] Thiazolo[3,2-a]Pyrimidine Via Cycloaddition Reactions

2018 ◽  
Vol 42 (9) ◽  
pp. 453-455 ◽  
Author(s):  
Demin Ren ◽  
Xiaolian Hu ◽  
Yulin Huang ◽  
Xiaofang Li
Keyword(s):  
Cycloaddition Reaction ◽  
Crystallographic Analysis ◽  
Azomethine Ylide ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
X Ray

The 1,3-dipolar cycloaddition reaction of ethyl 5-aryl-2-(2-methoxy-2-oxoethylidene)-7-methyl-3-oxo-2,3-dihydro-5 H-[1,3]thiazolo[3,2- a] pyrimidine-6-carboxylate and azomethine ylide, which was generated in situ by the reaction of 11 H-indeno[1,2- b]quinoxalin-11-one and L-proline, afforded novel 6″ethyl 1′-methyl 5″aryl-7″methyl-3″oxo-5’,6’,7’,7a′-tetrahydro-1' H,3″ H,5″ H-dispiro[indeno[1,2- b]quinoxaline-11, 3 ‘-pyrrolizine-2’,2″-[1,3]thiazolo[3,2- a]pyrimidine-1’,6″-dicarboxylates in good yields. The structures of all the products were characterised thoroughly by NMR, IR and HRMS together with X-ray crystallographic analysis.

Synthesis of Spiro[Pyrrolo[2,1-b][1,3]Benzothiazole-3,2′-[1,3]Thiazolo[3,2-a] Pyrimidine] via Cycloaddition Reactions

2018 ◽  
Vol 42 (5) ◽  
pp. 260-263 ◽  
Author(s):  
Qing Zeng ◽  
Demin Ren ◽  
Xingliang Fu ◽  
Xiaofang Li
Keyword(s):  
Cycloaddition Reaction ◽  
Crystallographic Analysis ◽  
Azomethine Ylide ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
X Ray

The 1,3-dipolar cycloaddition reaction of ethyl-5-aryl-2-[( Z)-2-methoxy-2-oxoethylidene]-7-methyl-3-oxo-3,5-dihydro-2 H-thiazolo[3,2- a] pyrimidine-6-carboxylates and azomethine ylide, which was generated in situ by the reaction of N-4-methoxyphenacylbenzothiazolium bromides and triethylamine, yielded novel 6′-ethyl-2-methyl-5′-aryl-1-(4-methoxybenzoyl)-7-methyl-3′-oxo-1,2-dihydro-5 H-spiro[pyrrolo[2,1- b][1,3]benzothiazole-3,2′-[1,3]thiazolo[3,2- a]pyrimidine]-2,6′-dicarboxylates in moderate yields. The structures of all of the products were characterised by NMR, IR, HRMS spectrometry, together with X-ray crystallographic analysis.

Synthesis of spiro[cyclopent-2/3-ene-1,2′-[1,3]thiazolo[3,2-a] pyrimidine] derivatives via 1,3-dipolar cycloaddition reaction of ethyl buta-2,3-dienoate

2018 ◽  
Vol 42 (12) ◽  
pp. 631-635 ◽  
Author(s):  
Demin Ren ◽  
Ye Tang ◽  
Xianyong Yu ◽  
Yulin Huang ◽  
Xiaofang Li
Keyword(s):  
Cycloaddition Reaction ◽  
Crystallographic Analysis ◽  
Dipolar Cycloaddition ◽  
Pyrimidine Derivatives ◽  
X Ray

The 1,3-dipolar cycloaddition reaction of ethyl (2Z)-5-aryl-2-(2-methoxy-2-oxoethylidene)-7-methyl-2,3-dihydro-5H-thiazolo[3,2-a] pyrimidine-6-carboxylate and ethyl buta-2,3-dienoate catalysed by triphenylphosphine afforded novel spiro[cyclopent-2-ene-1,2′-[1,3] thiazolo[3,2-a]pyrimidine] and spiro[cyclopent-3-ene-1,2′-[1,3]thiazolo[3,2-a]pyrimidine] derivatives in moderate yields. The structures of all the products were characterised thoroughly by NMR, IR and HRMS together with X-ray crystallographic analysis.

scholarly journals Utilization of 1-phenylimidazo[1,5-a]quinoline as partner in 1,4-dipolar cycloaddition reactions

2020 ◽  
Vol 75 (3) ◽  
pp. 259-267
Author(s):  
Areej M. Jaber ◽  
Jalal A. Zahra ◽  
Mustafa M. El-Abadelah ◽  
Salim S. Sabri ◽  
Monther A. Khanfar ◽  
...  
Keyword(s):  
Single Crystal ◽  
Spectral Data ◽  
Cycloaddition Reaction ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
Dimethyl Acetylenedicarboxylate ◽  
X Ray ◽  
X Ray Crystallography

AbstractA Selected set of 2-(quinolin-2-yl)-1,3-oxazepino[7,6-b]indoles 4a–d and dihydroacenaphtho[1,2-f][1,3]oxazepine 5 have been prepared via 1,4-dipolar cycloaddition reaction involving 1-phenylimidazo[1,5-a]quinoline, dimethyl acetylenedicarboxylate, and N-(substituted)isatins or acenaphthoquinone. Structures of the new heterocycles 4a–d and 5 are supported by NMR and HRMS spectral data, and confirmed by single-crystal X-ray crystallography for 4c and 5.

Spiroheterocycles via Regioselective Cycloaddition Reactions of Nitrile Oxides with 5-Methylene-1H-pyrrol-2(5H)-ones

2010 ◽  
Vol 63 (3) ◽  
pp. 445 ◽  
Author(s):  
Nicola J. Beattie ◽  
Craig L. Francis ◽  
Andris J. Liepa ◽  
G. Paul Savage
Keyword(s):  
Cycloaddition Reaction ◽  
Biphasic System ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
Nitrile Oxides ◽  
Facial Selectivity

Substituted 5-methylene-1H-pyrrol-2(5H)-ones underwent a 1,3-dipolar cycloaddition reaction with nitrile oxides to give the corresponding spiro heterocycles. Critical to this reaction was the development of a biphasic system for base-induced dehydrohalogenation of hydroximoyl chlorides, to give nitrile oxides, in the presence of a base-sensitive dipolarophile. A substituted N-tolyl 5-methylene-1H-pyrrol-2(5H)-one exhibited atropisomerism, which in turn led to a 4:1 facial selectivity during cycloaddition.

scholarly journals Enantioselective 1,3-Dipolar Cycloaddition Reaction of Nitrones with α-(Acyloxy)acroleins Catalyzed by Dipeptide-Derived Chiral Tri- or Diammonium Salts

Synlett ◽  
2019 ◽  
Vol 30 (15) ◽  
pp. 1835-1839 ◽  
Author(s):  
Chihiro Kidou ◽  
Haruki Mizoguchi ◽  
Tatsuo Nehira ◽  
Akira Sakakura
Keyword(s):  
Cycloaddition Reaction ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
Reaction Conditions

Organoammonium salts of dipeptide-derived chiral triamines or diamines with TfOH catalyzed the enantioselective 1,3-dipolar cycloaddition reactions of α-acyloxyacroleins with nitrones to give the corresponding adducts in good yields (up to 96%) and with high diastereo- and enantioselectivities (up to 89% ee). Although α-(p-methoxybenzoyloxy)acrolein is rather unstable under the reaction conditions, α-(3-pyrroline-1-carbonyloxy)acrolein is stable enough to be smoothly converted into the corresponding adducts with the aid of the chiral organoammonium salt catalysts.

Synthesis of Chromeno[3,4-c]Pyrazole from N-Tosylhydrazones and 3-Nitro-2-Phenyl-2H-Chromene

2017 ◽  
Vol 41 (12) ◽  
pp. 709-711 ◽  
Author(s):  
Xinliang Fu ◽  
Haotao Li ◽  
Demin Ren ◽  
Xiaofang Li
Keyword(s):  
Crystallographic Analysis ◽  
Dipolar Cycloaddition ◽  
X Ray

The intermolecular 1,3-dipolar cycloaddition of N-tosylhydrazones and 3-nitro-2-phenyl-2 H-chromene afforded 1-aryl-4-phenyl-2,4-dihydro-chromeno[3,4- c]pyrazoles in moderate to good yields. The structures of all the products were characterised by NMR, IR, HRMS and X-ray crystallographic analysis.

1,3-Dipolar Cycloadditions of a Chiral Oxazolidinone With Nitrones and Nitrile Oxides

1995 ◽  
Vol 48 (9) ◽  
pp. 1511 ◽  
Author(s):  
SG Pyne ◽  
J Safaei-G ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Hydrogen Atmosphere ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
The Novel ◽  
X Ray ◽  
Dipolar Cycloadditions ◽  
Nitrile Oxides ◽  
Exocyclic Methylene

The 1,3-dipolar cycloaddition reactions of the chiral oxazolidinone (1) and nitrones are highly regioselective and only 5,5-disubstituted isoxazolidine adducts are formed. These reactions occur under equilibrating conditions to give the more stable adducts that result from addition to the exocyclic methylene of (1) from the sterically more hindered π-face. The endo adducts are generally thermodynamically favoured. In one case the novel azetidine (21) was formed from the treatment of the adduct (4a) with palladium hydroxide on carbon under a hydrogen atmosphere. The major adducts from the reaction of (1) and nitrile oxides (16a,b) had the expected stereochemistry, addition of the 1,3-dipole having occurred from the less hindered π-face of the exocyclic methylene of (1). The stereochemistry of many of these products has been elucidated by single-crystal X-ray structural determinations.

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