Direct access to 1,4-disubstituted 1,2,3-triazoles through organocatalytic 1,3-dipolar cycloaddition reaction of α,β-unsaturated esters with azides

RSC Advances ◽  
2015 ◽  
Vol 5 (108) ◽  
pp. 88816-88820 ◽  
Author(s):  
Wenjun Li ◽  
Xiao Zhou ◽  
Yepeng Luan ◽  
Jian Wang

DBU-catalyzed organocatalytic 1,3-dipolar cycloaddition reactions of α,β-unsaturated esters with azides have been developed. This strategy generates 1,4-disubstituted 1,2,3-triazoles in high yields with high regioselectivities.

2016 ◽  
Vol 14 (23) ◽  
pp. 5246-5250 ◽  
Author(s):  
Xiao Zhou ◽  
Xianhong Xu ◽  
Zhenyan Shi ◽  
Kun Liu ◽  
Hua Gao ◽  
...  

Enolate-mediated [3 + 2] organocatalytic 1,3-dipolar cycloaddition reactions of β-functionalized ketones with nitrile oxides have been developed. This strategy could generate 3,4,5-trisubstituted isoxazole in high yields and regioselectivities.


2016 ◽  
Vol 40 (8) ◽  
pp. 6559-6563 ◽  
Author(s):  
Xianhong Xu ◽  
Zhenyan Shi ◽  
Wenjun Li

Enamine-mediated 1,3-dipolar [3+3] cycloaddition reactions of 1,2-cyclohexanedione with azides have been developed. This strategy could generate highly substituted 1,2,3-triazoles in high yields and high levels of regioselectivities. It is demonstrated that various types of products could be obtained with different organocatalysts and substrates.


2017 ◽  
Vol 15 (20) ◽  
pp. 4286-4290 ◽  
Author(s):  
Huijun Yuan ◽  
Lili Zhang ◽  
Zhantao Liu ◽  
Yang Liu ◽  
Jian Wang ◽  
...  

A NHC-catalyzed 1,3-dipolar cycloaddition reaction of allyl ketones with azides has been developed. This strategy could generate 1,4,5-trisubstituted 1,2,3-triazoles in high yields and regioselectivities in the presence of a 20 mol% N-heterocyclic carbene catalyst. A broad substrate scope of this process is also presented.


2016 ◽  
Vol 14 (42) ◽  
pp. 9985-9988 ◽  
Author(s):  
Wenjun Li ◽  
Xiao Zhou ◽  
Zhenyan Shi ◽  
Yang Liu ◽  
Zhantao Liu ◽  
...  

TMG-catalyzed [3 + 2] organocatalytic 1,3-dipolar cycloaddition reactions of allyl ketones with in situ generated nitrile oxides have been developed. This strategy could generate 3,5-disubstituted isoxazolines in high yields and regioselectivities.


2010 ◽  
Vol 63 (3) ◽  
pp. 445 ◽  
Author(s):  
Nicola J. Beattie ◽  
Craig L. Francis ◽  
Andris J. Liepa ◽  
G. Paul Savage

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.


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

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.


Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4416
Author(s):  
Vasilichia Antoci ◽  
Costel Moldoveanu ◽  
Ramona Danac ◽  
Violeta Mangalagiu ◽  
Gheorghita Zbancioc

We present herein a straightforward and efficient pathway for the synthesis of pyrrolophthalazine cycloadducts via Huisgen [3 + 2] dipolar cycloaddition reactions of phthalazinium ylides to methyl propiolate or dimethyl acetylenedicarboxylate (DMAD). A thoroughly comparative study concerning the efficiency of synthesis, conventional thermal heating (TH) versus microwave (MW) and ultrasound (US) irradiation, has been performed. The cycloaddition reactions of phthalazinium ylides to methyl propiolate occur regiospecific, with a single regioisomer being obtained. Under conventional TH, the cycloaddition reaction of phthalazinium ylides with DMAD occurs to a mixture of inseparable partial and fully aromatized pyrrolophthalazine cycloadducts, while MW or US irradiation are leading only to fully aromatized compounds, with the reactions becoming selective. A feasible mechanism for formation of fully aromatized compounds is presented. Besides selectivity, it has to be noticed that the reaction setup under MW or US irradiation offer a number of other certain advantages: higher yields, decreasing of the amount of used solvent comparative with TH, decreasing of the reaction time from hours to minutes and decreasing of the consumed energy; consequently, these reactions could be considered environmentally friendly.


2014 ◽  
Vol 16 (6) ◽  
pp. 3003-3006 ◽  
Author(s):  
Wenjun Li ◽  
Zhiyun Du ◽  
Jiayao Huang ◽  
Qianfa Jia ◽  
Kun Zhang ◽  
...  

A general organocatalytic 1,3-dipolar cycloaddition reaction between allyl ketones and various azides is reported. The reaction is catalyzed by a secondary amine to generate substituted 1,2,3-triazoles with high levels of regioselectivity.


Tetrahedron ◽  
1996 ◽  
Vol 52 (12) ◽  
pp. 4515-4526 ◽  
Author(s):  
S. Baskaran ◽  
J. Vasu ◽  
Ram Prasad.K. Kodukulla ◽  
Girish K. Trivedi ◽  
J. Chandrasekhar

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