A series of new maleimide monomers substituted with Schiff base moieties were synthesized via acid-catalyzed condensation of 3-(N-maleimidyl)phenyl hydrazide with aromatic aldehydes and ketones. The newly synthesized monomers were introduced in free radical chain growth homopolymerization producing five new polymaleimides with pendent Schiff base moieties .The new monomers were introduced also in free radical chain growth copolymerization with acrylonitrile producing new five copolymaleimides containing pendent Schiff base moieties. The new homopolymers and copolymers are of great importance since incorporation of bulky Schiff base moieties in their repeating units exhibit them better solubility and processing properties which made them suitable for a variety of important applications.
This research includes the synthesis of new bis-Schiff bases linked to different imide cycles. There were some steps involved in the synthesis of the novel Schiff bases with succinimide, phthalimide, tetrachlorophthalimide, and tetrabromophthalimide cycles. The first step involved the preparation of 4,4`-bis[(4-aminophenyl) methyl benzylidene]tolidine (1) via the condensation reaction of 3,3'-dimethyl-(1,1'-biphenyl)-4,4'-diamine with 4-amino acetophenone. In the second step, compound 1 reacted with various cyclic anhydrides, affording bis-amic acid Schiff bases 2-5. In the third step, the products 2-5 were dehydrated using the fusion method to prod
... Show MoreA series of new copolyimides containing pendant 1,3,4-oxadiazole moiety were synthesized via multisteps. In the first step five N-(5-substituted-1,3,4-oxadiazole-2-yl)maleamic acids were prepared via reaction of maleic anhydride with 2-amino-5-substituted-1,3,4-oxadiazoles. The obtained amic acids were dehydrated in the second step affording the corresponding N-(5-substituted-1,3,4-oxadiazole-2-yl) maleimides. In the third step the newly synthesized maleimides were introduced successfully in free radical copolymerization reaction with four vinylic monomers including acrylo nitrile, methacrylonitrile, methyl acrylate and methyl meth acrylate respectively producing twelve new copolymers having different physical properties which may serve
... Show MoreA series of Schiff bases linked to phthalimidyl phenyl sulfonate moiety have been synthesized via multistep synthesis. The first step involved reaction of phthalic anhydride with aniline producing N-phenyl phthalamic acid which was subsequently dehydrated to the corresponding N-phenyl phthalimide via treatment with acetic anhydride and anhydrous sodium acetate. The synthesized imide was treated with chlorosulfonic acid in the third step producing 4-(N-phthalimidyl) phenyl sulfonyl chloride which was introduced in reaction with 4-hydroxy acetophenone in the fourth step producing 4-[4-(N-phthalimidyl) phenyl sulfonate] acetophenone and this in turn was introduced successfully in condensation reaction with various aromatic primary amines affor
... Show MoreIn this work, a series of new maleimides linked to substituted benzothiazole moiety were synthesized. Synthesis of these new cyclic imides were performed via three steps, the first one involved preparation of a series of 2-aminobenzothiazole substituted with different substituents via reaction of different primary aromatic amines with ammonium thiocyanate and bromine in glacial acetic acid. The prepared 2- amino benzothiozoles were introduced in the second step in reaction with maleic anhydride producing a series of N-(substituted benzothiazole-2-yl) maleamic acids.The resulted maleamic acids were dehydrated in the third step via treatment with acetic anhydride and anhydrous sodium acetate to afford a series of the desirable N-(substitu
... Show MoreIn this present work, [4,4`-(biphenyl-4,4`-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)bis(2-methoxyphenl)(A1),4,4`-(biphenyl-4,4`-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)diphenol(A2),1,1`-(biphenyl-4,4`-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene) dinaphthalen-2-ol (A3)]C.S was prepared in 3.5% NaCl. Corrosion prevention at (293-323) K has been studied by using electrochemical measurements. It shows that the utilized inhibitors are of mixed type based on the polarization curves. The results indicated that the inhibition efficiency changes were used with a change according to the functional groups on the benzene ring and through the electrochemical technique. Temperature increases with corrosion current
... Show MoreI attended some amides non grassy substitutes such as acrylic compounds Amaid Electron Amaid and Alsinamamaid interaction unsaturated acids such as acrylic acid or Ketronk ????????? with primary amines Malkhtlfah of acrylic monomers Alamayd
Four N-substituted citraconisoimides were prepared via dehydration of the corresponding prepared citraconamic acids using N,N\-dicyclohexylcarbodiimide as dehydrating agent. The prepared citraconisoimides were introduced in free radical homopolymerization producing four new poly citraconisoimides. Also the prepared citraconisoimides were introduced in free radical copolymerization with three vinylic monomers including acrylonitrile, methylmethacrylate and methylacrylate producing new copolymers having different physical properties. Moreover two new phenolic resins containing pendent citraconisoimide moiety were prepared via condensation polymerization of N-(hydroxyphenol)citraconisoimide with formaldehyde. The new homopolymers and copoly
... Show MoreIn the present work, several new cyclic imides (succinimides) linked to benzothiazole or thiazole moieties through phenyl azo group were synthesized. Synthesis of the new imides was performed via multistep synthesis. The first step involved reaction of equimolar amounts of succinic anhydride and p-toluidine producing N-(4-tolyl) succinamic acid (1) which was dehydrated in the second step via treatment with acetic anhydride and anhydrous sodium acetate affording N-(4-tolyl)succinimide (2).
In the third step, substituted-2-aminobenzothiazoles were introduced in diazotization reaction with nitrous acid producing the corresponding diazonium salts and these inturn were introduced directly in coupling reaction with compound (2) affording th
The new Schiff base (L) “4‐[(2,4‐dimethoxy‐benzylidene)‐amino]‐1,5‐dimethyl‐2‐phenyl‐1,2‐dihydro‐pyrazol‐3‐one” was synthesized from 2,4‐dimethoxy‐benzaldehyde and 4‐amino‐1,5‐dimethyl‐2‐phenyl‐1,2‐dihydropyrazol‐3‐one, and the geometry of Schiff base was characterized and determined by proton nuclear magnetic resonance (1H‐NMR), mass, Fourier transform infrared (FT‐IR), and ultraviolet‐visible (UV‐vis) spectroscopy. Schiff complexes of Ni(II), Pd(II), Pt(IV), Zn(II), Cd(II), and Mg(II) have been prepared by reaction of ion metals with as‐prepared Schiff base. The results showed that synthesized complexes offered 1:2 m
Objectives: Two derivatives of cephalexin were synthesized by reaction with isatin-glycine Schiff base and bromoisatin-glycine Schiff base separately. Methods: Cephalexin was linked through the amine group to isatin glycine and bromoisatin glycine Schiff bases by amide bond formation. Results: These derivatives were characterized by FT-IR, H-NMR, elemental CHN analysis and then tested for their antimicrobial activity compared to cephalexin against gram-positive, gram-negative bacteria and Candida albicans fungi. Conclusion: The two compounds showed better activity against Staphylococcus aureus, compound 3b is more active against Escherichia coli, and compound 3a is more active against Klebsiella pneumonia.