2023-10

ORIENTAL JOURNAL OF CHEMISTRY (Issue : 5) (Volume : 39)

Over three major convenient steps, a series of some novel Bis-Schiff bases, and Bis 1,3-thiazolidin-4-one derivatives have been synthesized: Firstly, the etherification process through the reaction of the 4-hydroxybenzaldehyde substrate with o-, m-, and p-chlorobenzylchlorides under mild circumstances. Secondly, the condensation reaction between 4-((chlorobenzyl)oxy)benzaldehyde compounds with a number of aromatic diamines in an acidic environment produces the required Bis-schiff intermediates. Finally, the practical cyclization step was finished by synthesizing the required Bis 1,3-thiazolidin-4-one products with 79-97% yields through refluxing reaction in benzene with thioglycolic acid.

2022-09

Indian Journal of Heterocyclic Chemistry (Issue : 3) (Volume : 32)

Several new bis-Schiff bases and bis 4-thiazolidinone derivatives were synthesized through condensation and cyclization processes over two effective practical steps. The initial step included the synthesis of imine derivatives by the condensation reaction of 2-hydroxy-1-naphthaldehyde with various aromatic diamine substrates in existence of glacial CH3COOH as a catalyst. The second step involved reaction between bis-Schiff base derivatives with thioglycolic acid in anhydrous benzene to produce the desired 4-thiazolidinones.

2020-04

Oriental Journal of Chemistry (Issue : 2) (Volume : 36)

Due to the largely and an efficient usage of Weinreb amides or N-methoxy-N-methylamides as are remarkable intermediate in the organic synthesis field, the recent review paper provides a considerable development literature survey on the Weinreb amides synthesis. The direct transformation of carboxylic acids,acid chlorides, and esters to aldehydes or ketones employing organometallic reagents do not lead in high yields, since the high reactivity of ketone intermediates toward the organometallic reagents. While, the conversion to the appropriate Weinreb Amides, followed by treatment with the organometallic regent, result the stable expected ketones as the stable initial adduct toward further reactions. Furthermore, Weinreb amides undergo nucleophilic addition and produce a unique and steady five-membered cyclic intermediate which protects the over-addition, leading to a serious transformation.

2019-11

Res. J. Chem. Environ. (Issue : 9) (Volume : 23)

New Schiff base compounds have been prepared. Various aliphatic and aromatic ketones were condensed with naphthalene-1, 5-diamine to yield the desired Schiff bases. The structures of all the new products obtained in the present work are supported by spectral and analytical data (IR, NMR and Mass spectroscopy). Furthermore, the biological activity of Schiff Bases compounds was tested against two types of bacteria gram positive for the dye (Staphylococcus aureus) and gram-negative dye (E.Coli).

2019-10

Res. J. Chem. Environ. (Issue : 10) (Volume : 23)

This review highlights recent multicomponent reactions improvement in the synthesis of pyrano[2,3- c]pyrazole derivatives in presence of different catalysts including sodium benzoate, CAN, AmberlystA21, L- or S-proline, CTACl, n-TiO2/H14[NaP5W30O110], SiO2TMG,Fe3O4, DMAP, MS 4Å, DABCO, NH4H2PO4/Al2O3,SnO2QDs, CAPB, BF3/MNPs, (Ni 0.5 Zn0.5Fe2O4@Hap-Cs2CO3), VB1, ZrO2 NPs,βCD,TUD, urea, NaBr, MMT-ZSA, piperidine, NMOAg2O, InCl3, PEG-400, NaF and SiO2. In this context, modern routes in the preparation and use of pyrano[2,3-c]pyrazole as a pioneer for the heterocyclic framework are based on three- or fourmulticomponent reaction of ethyl acetoacetate, hydrazine or phenylhydrazine, aromatic aldehyde and malononitrile substrates in presence of catalyst.

2019-09

Oriental Journal of Chemistry (Issue : 6) (Volume : 35)

N-methoxy-N-methyl amides or Weinreb amides are worthy embranchment of amide group and their rich functional groups in organic synthesis become a strong else unfeasible conversion. Weinreb amides are produced as an intermediate product of the reaction of carboxylic acids, acid chloride or esters with organometallic reagents, which was first uncovered in 1981. The direct conversion of carboxylic acids or acid chlorides or esters to ketones or aldehydes using organometallic reagents do not lead in high yields, because the intermediate ketones are still highly reactive toward the organometallic reagent. However, after derivatization to the corresponding Weinreb amide, reaction with organometallics does give the desired ketones, as the initial adduct is stabilized and doesn't undergo further reactions. A nucleophilic addition to the Weinreb amides results in a unique and stable five-membered cyclic tetrahedral intermediate which protects the over-addition, leading to a selective conversion.

2019-04

Indian Journal of Heterocyclic Chemistry (Issue : 2) (Volume : 29)

The present work describes the synthesis of new 1,5-naphthyridine derivatives. The procedure is based on the cross-coupling reaction of commercially available 2-iodo-1,5-naphthyridine with aromatic and heteroaromatic boronic acids through the Suzuki reaction. This process furnished the desired products in high yields. The structures of all the new products obtained in this work are supported by spectral and analytical data.

2019-04

Oriental Journal of Chemistry (Issue : 2) (Volume : 35)

A novel and an efficient strategy of fused tricyclic quinoline heterocycle compounds from aliphatic amino carboxylic acid substrates was studied. The protocol here is proceed over main reaction processes including: cyclization, protection, amidine formation, further cyclization and finally coupling with boronic acid substrate through Suzuki reaction. These reactions afforded the corresponding products in high yields. Furthermore, all synthesized compounds were identified by spectral data.

2019-01

Chemistry–A European Journal (Issue : 10) (Volume : 23)

The three-component free-radical carbo-alkenylation of electron-rich olefins has been studied, varying the substitution pattern in the alkene, in the radical precursor and in the final acceptor. New vinylsulfones were also prepared and their reactivity investigated. The scope and limitations of the process was established, and the reaction mech anism clarified using selected dienes as radical clocks. It was thus recognised that the reversible addition onto the olefin of the released sulfonyl group is an important event, which should not be overlooked when using such multicomponent carbo-alkenylation reactions.

2019-01

Indian Journal of Heterocyclic Chemistry (Issue : 1) (Volume : 29)

facile and suitable method for the synthesis of different 1, 8-Naphthyridine derivatives is depicted. The procedure is based on the diazotization and triflation reactions of commercially available 1, 8-naphthyridine-2-amines followed by cross-coupling with aromatic and heteroaromatic boronic acids through Suzuki reaction. These processes reserved the required yields in high percentage. All synthesized compounds were identified by spectral data.

2019-01

Asian Journal of Chemistry (Issue : 1) (Volume : 31)

This review highlights the most recent syntheses of free radical reactions, which included numerous processes (photoredox catalysis freeradical reactions, free-radical cascade processes reactions, Minisci-type free radical alkylation reactions and metal-catalysis free radical reactions). A photoredox-catalyzed C–H functioning of aromatic heterocyclic utilizing an assortment of various, alkyltrifluoroborates has been mentioned. Utilizing organo-photocatalyst and a moderate oxidant, conditions malleable for functionalizing complex aromatic heterocyclics are outlined to prepare a oriental agent for late-stage derivatization. Radical alkylations of aromatic heterocyclic (Minisci reactions) appear a more direct functionalization of particular, C–H bonds. For the ground mentioned above, alkylation designing using radical have recently risen to significance for the late-stage functionalization of aromatic heterocyclic framework. Therefore, this issue is the primary point of the present survey, which thinks about work from the most recent five years. The work is ordered by the key procedures associated with the synthesis of free-radical reactions, planning to give researchers a simple comprehension of this free radical–reactions-based science and to give bits of knowledge to provide insights for further investigations.

2018-12

Oriental Journal of Chemistry (Issue : 6) (Volume : 34)

This review highlights recent improvement in trifluoromethylene functionalization processes with CF3 reagents, includes: Togni’s, Umemoto’s, CF3SO2Cl, CF3I, Yagupol’skii-Umemoto, TMSCF3, Langlois (CF3SO2Na) and clarifies the several designing to result the corresponding trifluoromethylated products. In this article, the selective trifluoromethylation reactions with Togni’s reagents and their analogs are detailed, which work transition metals or photoactivated Ru or Ir catalysts as single electron giver to yield CF3 radical intermediate species. This issue is to introduce a draft of diverse reports, presenting the modern reaction collect and mechanics produced during the past five years. This task is demanded by the key protocol connected with the trifluoromethylation reactions, designing to sustain researchers a straight forward understanding of such reactions and to award information for further implements.

2018-10

Indian Journal of Heterocyclic Chemistry (Issue : 4) (Volume : 28)

This review highlights recent advances in catalytic enantioselective halofunctionalization of alkenes and explains the various planning to bring about regio- or stereoselective transformations. Halocyclization of olefinic substrates is an encouraging organization in creating O- and N-heterocyclic compounds, which additionally connotes the advancement of their asymmetric variations. The initiation of alkenes and their ensuing functionalization is an as often as possible utilized system in synthetic chemistry. The degree and difficulties of intra- and inter-molecular reaction variations have well talked about. The point is to give an outline of different reports, featuring the new reaction composes and techniques created amid the previous 5 years.

2018-07

Oriental Journal of Chemistry (Issue : 4) (Volume : 34)

In recent years, an interest in the synthesis of crown ether Schiff bases and their complexes has been increased, due to the significance and broadly the uses of these compounds in various fields. The present review paper outline extensive recent advances literature survey on the crown ether including azomethine group and their complexes with the tough and easy granter atoms, has been reconsidered. Emphasis has been done on element complexation with crown ether holding Schiff bases to enable the researchers to procure valuable information of the chelating activity of crown ether containing azomethine group and their enforcement.

2017-10

Indian Journal of Heterocyclic Chemistry (Issue : 4) (Volume : 27)

A convenient procedure for the preparation of variously substituted quinolines is described. The new method is based on Mitsunobu reaction of aromatic amines with phosphonium yields. Facile onepot synthesis of quinolones derivatives involving an Aza-Wittig reaction of aryliminophosphorane with substituted aldehydes and cyclization of intermediates was achieved under basic conditions.

2017-07

Indian Journal of Heterocyclic Chemistry (Issue : 3) (Volume : 27)

An efficient one-pot synthesis of imidazo-dipyrimidine-4,9(3H)-diones and pyrimidopyrazinopyrimidine-4,10(3H,6H)-diones was developed using novel Vilsmeier reagent. A mixture of 5-ethyl-5-methyl-2,4-imidazolidine-dione or 2,5-piperazine-dione and substituted amino esters underwent cyclization at ambient temperature in dry dichloromethane to afford the desired products. The structures of all the new products obtained in the present work were supported by spectral and analytical data (infrared, nuclear magnetic resonance, and mass spectroscopy).

2017-03

Indian Journal of Heterocyclic Chemistry (Issue : 1) (Volume : 27)

The reaction of ethyl 2-aminobenzoate with different substituted amide compounds led to cyclization through Vilsmeier intermediate in dry dichloromethane and ambient temperature, affording the 4(3H)-quinazolinone derivatives with higher yields. The structures of all the new products obtained in this work are supported by spectral and analytical data (infrared, nuclear magnetic resonance, and mass spectroscopy).

2015-10

J. Indian Chem. Soc. (Volume : 92)

The addition of electrophilic precursors such as benzylketone and weinreb amide xanthate across the double bond of unactivated olefins provides access to the corresponding three-component adducts in good to the excellent yields under mild conditions.

2015-09

Oriental Journal of Chemistry (Volume : 31)

Addition of functionalized carbon fragments across the olefinic π-system through a freeradical carbo-oximation process offers a straightforward access to valuable intermediatesfor organic synthesis. For this purpose, we designed a new protectedsulfonyl oxime, which enable rapid radical addition with high yields under mild conditions.

2015-08

Oriental Journal of Chemistry (Issue : 3) (Volume : 31)

In this paper the synthesis of some substituted 1,3,4-oxadiazoles, 1,3,4-thiadiazoles and 1,2,4-triazoles was achieved. 2-(2,3-dimethyl phenyl amino) benzoic acid was esterified to its ethyl ester by its reaction with absolute ethanol in presence of concentrated sulfuric acid. The ethyl ester was treated with hydrazine hydrate in ethanol to give the corresponding hydrazide. The hydrazide was converted to substituted thiosemicarbazide by its reaction with ammonium thiocyanate. The thiosemicarbazide was treated with sodium hydroxide solution and with sulfuric acid to give 5-(2,3-dimethyl phenyl amino phenyl)-1,2,4-triazole3-thiol and 2-(2,3-dimethyl phenyl amino phenyl)-5-amino-1,3,4thiadiazole respectively. The acid hydrazide was treated with substituted benzaldehyde to give hydrazones which cyclized to disubstituted 1,3,4oxadiazole, while the reaction of hydrazide with formic acid followed by cyclization of formyl hydrazine by PbO2 to give monosubstituted 1,3,4oxadiazole. Finally, treatment of hydrazide with carbon disulfite in alcoholic potassium hydroxide gave 2-(2,3-dimethyl phenyl amino phenyl)-1,3,4-oxadiazole-5-thiol. The structures of the synthesized compounds were confirmed by physical and spectral means.

2015-08

Oriental Journal of Chemistry (Issue : 4) (Volume : 31)

A convenient procedure for the preparation of various naphthyridine constructions is described. The method is based on the Vilsmeier, cyclization and Suzuki reactions of piperidinone with substituted aniline. The reactions provided the desired fused tricyclic heterocycles products in high yields.

2015-06

Organic letters (Issue : 18) (Volume : 17)

The first total synthesis of eucophylline was reported in 10 steps and 10% overall yield. The naphthyridine core of eucophylline was prepared through the coupling between a strained azabicyclo[3.3.1]nonan-2-one and a trisubstituted benzonitrile, followed by a cyclization of the corresponding amidine. This coupling reaction was shown to proceed through a stable bicyclic chloroenamine intermediate. The azabicyclo[3.3.1]nonan-2-one skeleton was in turn accessible through a straightforward sequence including a free-radical three-component olefin carbo-oximation as a key step

2014-12

https://tel.archives-ouvertes.fr/tel-01412881

The aim of this work was to develop new radical multi-component processes and their application in organic synthesis. Carbo-alkenylation processes were thus performed with new radical precursors, different olefins, in the presence of Zdiphenylsulfonylethylene as a terminal acceptor. Reaction conditions have also been optimized, including the diphenylsulfonylhydrazine as a radical initiator under U.V. irradiation, and substitute to the costly DTBHN. Tin-free conditions were also screened with the goal of replacing (Bu3Sn)2 with silyl radicals. Tris(trimethylsilyl)silylthiopropene was tested with success as a radical chain carrier. After this methodology studies, we developed a strategy toward the synthesis of Eucophylline, an alcaloid isolated from Leuconotis griffithii, which tetracyclic skeleton was elaborated based on a carbooximation of olefin. This multicomponent process, followed by a reduction of the oxime function and a lactamization offered a fast access to the bicyclo[3.3.1]lactam, a keyintermediate in the synthesis. A Friedländer-type reaction between this lactam and an ortho-aminobenzonitrile allowed an access to the Eucophylline tetrahydrobenzo[1,8]naphthyridine skeleton. The synthesis of the model compound was finally completed with the introduction of the vinylic substituent through a Heck coupling.

2009-09

Journal of Education and Science (Volume : 22)

Synthesis of Subsituted-1,3,4-Oxadiazoles-1,3,4-Thiadiazolesand1,2,4-Triazolesfrom-2-(2,3-dimethy lphenyl amino) benzoic acid

2009-04

Journal of Education and Science (Issue : 29) (Volume : 22)

Synthesis of some Substituted-1,3,4-Oxadiazoles, Thiadiazoles and 1,2,4-Triazoles

2007-11

National Journal of Chemistry (Volume : 25)

Synthesis and Antibacterial Activity of 2-Cinnamyl -5-Subsituted-1,3,4-Oxadiazole-1,3,4-Thiadiazoles and 5-Cinnamyl-3- Subsituted-1,2,4-Triazoles

2001-12

University of Mosul (Volume : 4)

Thesis