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Synthesis Of New Asymmetrical Pyromellitdiimides Derived From Pyromellitic Dianhydride

This work involves the synthesis and characterization of asymmetrical pyromellitdiimide
derivatives [IV]a-f
by four sequence steps selective reaction . One mole of pyromellitic dianhydride
was reacted with one mole of various primary aromatic amines [ 4-nitro aniline , 4-chloro aniline , 4-toludine and 4-anisidine] in excess of dry acetone to produce six compounds (N-substituted-pyromellitamic monoacid) [I]a-f . These new compounds [I]a-d were converted to the corresponding
N- substituted- pyromellitmonoimide [II]a-d via their heating at (80-90)
0
C in sodium acetate-acetic
anhydride mixture .
The compounds [II]a-f
were allowed to react with one mole of another primary amines in
excess of dry acetone to give new derivatives of amic acid [II]a-d followed by intramolecular
cyclization reaction of these compounds [IV]a-f in sodium acetate-acetic anhydride system to yield the
desired asymmetrical pyromellitdiimide derivatives [IV]a-f
, the above reactions can be summarized in
Scheme 1.
All the synthesized compounds have been studied and charachterized by their melting points
, FTIR , and
1
HNMR spectroscopy (for some of them)

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Publication Date
Mon Apr 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Characterization of New Heterocyclic Derived from Pyromellitic Dianhydride

  In this work two moles of 2-amino benzothiazole were allowed to react with one mole of pyromellitic dianhydride to produce N,N‾-Bis-(benzathiazol-2-yl) pyromellitamic diacid [I] which was submitted to esterification via the reaction with dimethyl sulphate in sodium carbonate in acetone as a solvent to synthesize N,N‾-bis-(benzothiazol-2-yl) pyromellitam diacetate [II] .This ester  was used to produce  novel  compounds through  two paths :- Path one:- Reaction of ester [II] with hydrazine in ethanol as a solvent to form the corresebonding  N,N‾-bis (benzothiazole-2-yl) –pyromellitamic acid hydrazide [III] which react with acetyl acetone in ethanol or with phthalic anhydride in dioxa

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Publication Date
Thu Apr 13 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Novel Schiff Bases Derived From Pyromellitic Dianhydride

   The new Schiff bases derived from pyromellitic dianhydride were   synthesized  by  several  steps  reaction . A symmetrical  diamic acide  [I ]a-c  were  synthesized  by  the  reaction  of  pyromellitic  dianhydride  with  some aromatic  amines  (containing  electron  withdrawing , repulling  groups ) in dry acetone.      In the second step the  diacids were converted  to  their corresponding  diimide [II ]a-c using acetic anhydride and sodium acetate system as a dehydrating agent,    via  the  intra molecular  cyclization  steps&nbs

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Publication Date
Sun Apr 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Evidence Supports The Formation Of Isoimides Derived From Pyromellitic Dianhydride

    Some new mono isoimides of asymmetrical pyromillitdiimide derived from pyromellitic dianhydride were synthesized and studied by their melting points , FTIR , and 1HNMR spectroscopy and C.H.N analysis (for some of them) and it was proved that the mechanism of the formation of these isoimides followed , the mechanism suggested by Cotter et al . by using N, N─- dicyclohexylcarbodiimide as dehydrating agent , in spite of the groups attached to the phenyl moiety as mentioned in literatures .

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Publication Date
Sun Apr 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Science
Evidence Supports The Formation Of Isoimides Derived From Pyromellitic Dianhydride

Some new mono isoimides of asymmetrical pyromillitdiimide derived from pyromellitic dianhydride were synthesized and studied by their melting points, FTIR, and 1HNMR spectroscopy and CHN analysis (for some of them) and it was proved that the mechanism of the formation of these isoimides followed, the mechanism suggested by Cotter et al. by using N, N─-dicyclohexylcarbodiimide as dehydrating agent, in spite of the groups attached to the phenyl moiety as mentioned in literatures.

Publication Date
Wed Mar 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
New Schiff – Bases Prepared From Pyromellitic Dianhydride Via Its Hydrazide Derivative

N, N′- bis[4-hydroxy phenyl] pyromillitdiimide [II] was prepared from the corresponding diamic acid , which was transfered to its new ester by the reaction with chloroethyl acetate [III ], [III] was used to prepare the novel hydrazide derivative [IV] , which was allowed to react with several aldehydes to yield the hydrazones [V – IX]. All the new compounds were synthesized , and characterized by their melting points .HNMR for some of them1FTIR,C,H,N analysis and ,

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Publication Date
Wed Mar 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
New Schiff – Bases Prepared From Pyromellitic Dianhydride Via Its Hydrazide Derivative

N, N′- bis[4-hydroxy phenyl] pyromillitdiimide [II] was prepared from the corresponding diamic acid , which was transfered to its new ester by the reaction with chloroethyl acetate [III ], [III] was used to prepare the novel hydrazide derivative [IV] , which was allowed to react with several aldehydes to yield the hydrazones [V – IX]. All the new compounds were synthesized , and characterized by their melting points .HNMR for some of them1FTIR,C,H,N analysis and ,

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Publication Date
Wed Apr 19 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis of New Asymmetrical Pyromellitdiimide and Their Amic Acids Containing Heterocyclic Unit

This work involves the synthesis and characterization of  asymmetrical  pyromellitdiimide derivatives [VII]a-f  by four sequences steps reaction . One mole of pyromellitic dianhydride was reacted with one mole of various primary aromatic amines [2aminothiazole , 2-aminobenzothiazole , 5-(4-amino phenyl)-1,3,4-oxadiazole-2-thiol , 4-nitro aniline , 4-chloro aniline , 4-toludine] in excess of dry acetone to produce six compounds (Nsubstituted-pyromellitamic monoacid) [IV]a-f . These new compounds [IV]a-f  were converted to the  corresponding N- substituted- pyromellitmonoimide [V]a-f  when heating then at (8090) 0C in sodium acetate-acetic anhydride system .The compounds [V]d-f were allowed to react with one m

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Publication Date
Sun Dec 04 2016
Journal Name
Baghdad Science Journal
Synthesis of new Polyimides Derived from 4- minoantipyrine

In the present study, new five polymers of acryloyl chloride have been synthesized by reaction 4-aminoantipyrine with many substituted acid chloride (A-E). Then condensation of polyacryloyl chloride with the product in one step (A-E), in a suitable solvent in the presence amount of (Et3N) to obtain new polyimides(A1-E5). The prepared compounds were characterized by UV. FT-IR, 1H-NMR and 13C-NMR spectroscopy and measuring of other physical properties such as softening point, melting point and solublities.

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Publication Date
Sun Jul 02 2023
Journal Name
Iraqi Journal Of Science
Synthesis of New Heterocyclic Compounds Derived From 5,10- dihydrophenophosphazine

This work comprises the synthesis of 18 new N- substituted 5,10-
dihydrophenophosphazine.The diphenylamine was chosen as the starting material ,
which was reacted with phosphorus trichloride at elevated temperature (200-220)0C
for 6 hrs, followed by treating the reaction mixture with water to yield 5,10-
dihydrophenophosphazine-10-oxide(1), this was reacted with ethylchloroacetat to
obtain ethyl(5,10-dihydrophenophosphazine-10- oxide)acetate(2). Compound (2)
was converted to acid hydrazide by treating with hydrazine hydrate( 98% ) to obtain
5-(5,10-dihydrophenophosphazine) acetohydrazide-10-oxide (3). The acid hydrazid
was used to react with phenylisocyanat , phenylthioisocyanat to give (4,7)
respectively which

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Publication Date
Sun Mar 01 2009
Journal Name
Baghdad Science Journal
Synthesis of Some New 1,2,4-Triazoles Derived from 2-Mercaptobenzimidazole

New 1,2,4-triazole derivatives of 2-mercaptobenzimidazole (MB) are reported. Ethyl (benzimidazole-2-yl thio) acetate (1) has been prepared by condensing 2-mercaptobenzimidazole with ethylchloroacetate. The ester (1) on reacting with hydrazine hydrate gave the corresponding acetohydrazide(2)which was reacted separately with phenylisocyanate and phenylisothiocyanate, followed by ring closure in an alkaline medium giving 3-[(benzimidazole-2-yl thio) methyl]-4-phenyl-1,2,4-triazole-5-ol and 3-[(benzimidazole-2-yl thio) methyl]-4-phenyl-1,2,4-triazole-5-thiol respectively (6,7). Reaction of acetohydrazide (2) with CS2 and ethanol/KOH, gave dithiocarbazate salt (8). Cyclization of (8) with hydrazine hydrate gave 3-[(benzimi

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