1,3-Dipolar Cycloaddition Reactions of the Ylide Derived from 6-Phenacyl-benzo[f][1,7]naphthyridinium Bromide

1999 ◽  
Vol 52 (2) ◽  
pp. 149 ◽  
Author(s):  
Grazyna Matusiak
Keyword(s):  
Maleic Anhydride ◽  
Methyl Methacrylate ◽  
Methacrylic Acid ◽  
Basic Medium ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
Dimethyl Acetylenedicarboxylate ◽  
Methyl Vinyl ◽  
Acid Methyl

The 1,3-dipolar cycloaddition reactions of 4,6-diazaphenanthrene 6-phenacylide formed in situ from the quaternary 6-phenacylbenzo[f][1,7]naphthyridinium bromide in basic medium were examined; methacrylic acid, methyl methacrylate, butyl vinyl ether, methyl vinyl ketone, maleic anhydride and dimethyl acetylenedicarboxylate were used as the dipolarophiles.

scholarly journals Huisgen [3 + 2] Dipolar Cycloadditions of Phthalazinium Ylides to Activated Symmetric and Non-Symmetric Alkynes

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4416
Author(s):  
Vasilichia Antoci ◽  
Costel Moldoveanu ◽  
Ramona Danac ◽  
Violeta Mangalagiu ◽  
Gheorghita Zbancioc
Keyword(s):  
Reaction Time ◽  
Comparative Study ◽  
Cycloaddition Reaction ◽  
Environmentally Friendly ◽  
Dipolar Cycloaddition ◽  
Cycloaddition Reactions ◽  
Dimethyl Acetylenedicarboxylate ◽  
Thermal Heating ◽  
Dipolar Cycloadditions ◽  
Methyl Propiolate

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.

The Cycloaddition Reactions of Some 7-Alkylidenecycloocta-1,3,5-trienes

1990 ◽  
Vol 43 (3) ◽  
pp. 463 ◽  
Author(s):  
PH Ferber ◽  
GE Gream ◽  
PK Kirkbride ◽  
ERT Tiekink
Keyword(s):  
Maleic Anhydride ◽  
Cycloaddition Reactions ◽  
Dimethyl Acetylenedicarboxylate ◽  
Chlorosulfonyl Isocyanate ◽  
Diethyl Azodicarboxylate

A number of 7-alkylidenecycloocta-1,3,5-trienes, all unstable, yield novel π8+π2 cycloadducts with a range of π2-addends. The reactions of 7-methylenecycloocta-1,3,5-triene with ethene-tetracarbonitrile, 4- phenyl-1,2,4-triazoline-3,5-dione, diethyl azodicarboxylate and chlorosulfonyl isocyanate are described. The tetraene did not react with maleic anhydride or dimethyl acetylenedicarboxylate. As well, the reactions of 1,3,5-trimethyl-7-methylenecycloocta-1,3,5-triene, 2,9a- dihydro-1H-cyclopentacyclooctene and 1,2,3,10a- tetrahydrobenzocyclooctene with ethenetetracarbonitrile and of 7- isopropylidenecycloocta-1,3,5-triene with 4-phenyl-1,2,4-triazoline- 3,5-dione are discussed. The intermediacy of homotropylium zwitterions in the reactions is postulated.

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