DADAEI AND NAEIMI
9 of 10
from the reaction mixture by external magnet and then
allowed the filtrate to react further at the other half time
of the reaction. The results showed any further product
after the separation of the catalyst, and thus, the catalyst
acts heterogeneously in the reaction media without any
leaching its active cites.
AUTHOR CONTRIBUTIONS
Mahla Dadaei: Data curation; formal analysis; method-
ology. Hossein Naeimi: Methodology; supervision.
DATA AVAILABILITY STATEMENT
The data that support the findings of this study are avail-
able in the supporting information of this article.
In
a
plausible mechanism, at first, ethyl
acetoacetate is activated by catalyst and attacks to the
carbonyl group of aryl aldehyde. Then, in second step,
hydrazine attacks to the carbonyl group of substance I
and removes the H2O and EtOH. At this time, the
intermediate II is formed. Furthermore, the reaction
between the catalyst and malononitrile gives product
III. Then, the reaction occurs between substance III
and intermediate II and led to the intermediate IV
production; then the oxygen nucleophilic attack on
the carbon is carried out, and after the electron
bond movement, the final product is produced
(Scheme 3).
ORCID
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ACKNOWLEDGMENT
The authors are grateful to University of Kashan for
supporting this work by grant no. 159148/86.
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