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Synthesis of New Pyrazoline- Phenoxathiinderivatives

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Synthesis of New Pyrazoline- Phenoxathiinderivatives Baghdad Science Journal Vol.10(2)2013 Synthesis of New Pyrazoline- PhenoxathiinDerivatives Suad M. AL-Araji*Ayad Ahmed Mohamad** Received 23, February, 2012 Accepted 29, August, 2012 Abstract: Phenoxathiinwas prepared by the reaction of diphenyl ether with sulfur in the presence of anhydrous aluminum chloride.This work comprised the synthesis of newphenoxathiin derivatives containing heterocyclic moieties. These heterocyclic compounds were synthesized in three groups. The first group was made up of 2- (oxoalken-1-yl) phenoxathiin derivatives (3a-3j) obtained from the reaction of2- acetylphenoxathiin with different aromatic aldehyde in the presence of sodium hydroxide. The othertwo groups involved compounds produced from the reaction of (3a-3j)with hydrazine hydrate in acetic acid to get 2-(1-acetylpyrazolin-3-yl) phenoxathiin derivatives (4a-4j), and phenyl hydrazine in the presence of piperidineto afford 2-(1-phenylpyrazolin-3-yl) phenoxathiin derivatives (5a-5j).All these compounds of two groups above were substituted in position (5) in pyrazoline ring with different aryl groups according to aromatic aldehyde used in the preparation of the first group series compounds. Keywords:Phenoxathiin, Oxoalken derivatives, Pyrazoline. Introduction: brown dyes on cotton [14]. Alkylated Phenoxathiin is given as the preferred phenoxathiin has excellent oxidative name by Patterson and Capell[1-3]. stability and excellent anti-wear Most widely method of preparation of properties, so they are beneficial as phenoxathiinhas been used alkyl lubricant additives, lubricant base phenoxathiinoxides by Ferrario[4- stocks, or intermediates to lubricant 10]and dioxides of base stock to improve viscosity and cycloalkylphenoxathiins and their wear properties [15]. In biological halogen derivatives have been field, they are used in many drugs as recommended as modifiers in plastic bacteriostatic, fungicides, anthelmintic, materials, intermediates antioxidants insecticides and antiviral agents such and as rubber and gum inhibitors[11- as distemper virus, influenza virus, 13]. Several of crystalline hepatitis virus, neurotropic virus and phenoxathiincationradicals have especially influenza and herpetic allowed us to be studying the viruses [16]. The phenoxathiin and its chemistry of the cation radical in derivatives are used subunits to homogenous solution. Several of prepared different compounds phenoxathiin compounds are reddish exampledihydroazulenes(DHAS)[17]. *Department of Chemistry, College of Science, University of Baghdad, Baghdad-Iraq **Department of Research and Quality Control, Daura Refinery, Ministry of Oil 405 Baghdad Science Journal Vol.10(2)2013 Polyimides were readily prepared by maintained on steam bath for 4 hrs.The the polycondensations of reaction mixture was poured slowly, phenoxathiindiamines with aromatic with stirring, into ice bath to which diacyl chlorides and aromatic diamines (25 ml.) of concentrated hydrochloric with new phenoxathiindiacyl acid was added. After the two layers chlorides[18]. The acetyl derivatives were separated the water layer was are obtained by the action of acetyl discarded and the (phenyl ether- chloride on the amino phenoxathiin) layer dried overnight acid.Phenoxathiin derivatives have with calcium chloride, this mixture recently gained attention owing to was distilled at (5 mm.) pressure from their fluorescent properties [19,20]. a 500-ml specialClaisen flask. After Organometallic derivatives of removal of the phenyl ether the phenoxathiin have been prepared with fraction boiling at (140-160ºC / 5mm.), different elements such as lithium and phenoxathiin was collected at (150- silicon [21-31]. 152)ºC. The product was crystallized Materials and Methods: from methyl alcohol, m.p.(56- FT-IR spectra were recorded on 57)ºC,yield80%.2- [SHIMADZU] FT-IR 8400s acetylphenoxathiin(2) spectrophotometer; Solid samples were A mixture of (22.9 g, 0.114 mol) run in KBr disc, Liquid were run as phenoxathiin, (9.7 g, 0.155 mol, 8.8 smears. UV spectra were recorded on ml) acetyl chloride and carbon UV-Visible Spectrophotometer disulphide (120 ml) was stirred while 1 [SHIMADZU] UV-160A. H-NMR anhydrous aluminum chloride (15.5 g, spectra were recorded on ultra sheild 0.116 mol) was added in small 300 MHz with tetramethylsilane as portions. The red mixture was stirred internal standard. Melting points were for(2hrs.) at room temperature and determined in a [GallenKamp] melting refluxed on the water bath for a further point apparatus with sample contained (24 hours), the mixture was cooled, in open capillary glass tube in an poured on to a mixture of ice and electrically heated metal block hydrochloric acid, product was apparatus. Thin Layer crystallized once from ethanol and Chromatography[TLC]was performed twice from petroleum ether b.p.(80- on pre-coated plastic sheet with 0.25 100)ºC, m.p. 112ºC, yield 52.5%. IR: mm layer of silica-gel F254. Spots 1665 cm-1 (C=O)str.Part One were detected with iodine vapour. 2-(oxoalken-1-yl) phenoxathiin General procedure for derivatives (3a-3j) synthesis of phenoxathiin A mixture of (3g, 0.013 mol) 2- andits acetylphenoxathiin and (1.56 g , derivativesphenoxathiin(1) 0.0147 mol) of appropriate A mixture of 188.6 g. (1.1 mol) of benzaldehyde in (80 ml) of ethanol and phenyl ether, 25.6 g. of sulfur (1.5ml) of (1% NaOH) solution was (flowers) and 51.0g. (0.38 mol) of refluxed for (2 hrs). The reaction anhydrous aluminum chloride, mixture was poured in cold water, the 406 Baghdad Science Journal Vol.10(2)2013 precipitate filtered off and (ethanol-water) (3:1) to give (5a), the recrystallized from (ethanol-water) following compounds were prepared in (3:1) to give (3a-3j).FT-IR spectra of this manner. FT-IR spectra of this these compounds showed (C=O)str. compound and the following band at (1670-1685)cm-1 and (1608- compounds showed absorption bands 1600) cm-1 aliphatic (C=C)str. Table at (1460-1600)cm-1 aromatic (C---- (1) represent the physical data of C)str., (1681-1682)cm-1 (C=N)str. and compounds (3a-3j).Characteristic (1249-1355)cm-1 (C-N)str. Table (5) bands ofFT-IRspectra of compounds represent the physical data of (3a-3j) are listed in Table (2). compounds(5a-5j).Characteristic bands Part Two ofFT-IRspectra of compounds (5a-5j) 2-(1-acetylpyrazolin-3-yl) are listed in Table (6).Results and phenoxathiin derivatives(4a-4j) Discussion: To a solution of 2-(3-phenyl-1- Phenoxathiin reacted with acetyl oxypropen-1-yl) chloride in dry carbon disulfide in phenoxathiin(3a)(0.313g, 0.001 mol) presence of anhydrous aluminum in acetic acid (96%, 1 ml) hydrazine chloride to get 2-acetyl hydrate (0.4 ml, 0.008 mol) was added phenoxathiinthroughFriedel Crafts and the mixture was refluxed for 5 hrs., acylation method. FT-IR spectrum of the product separated and out on phenoxathiin showed strong bands at -1 cooling was crystallized from (ethanol- 3063 cm aromatic (C-H) str., 1585 -1 -1 water) (3:1) to give (4a), the following cm and 1450 cm assigned to the ----- compounds were prepared in this aromatic stretching system (C C)str, -1 -1 manner. FT-IR of these compounds 1219 cm and 1026 cm assigned to 1 showed absorption bands at (1460- asym. and sym. (C-O-C)str. The H- 1585) cm-1 aromatic (C----C)str., NMR spectrum showed signals (1597-1612) cm-1 (C=N)str. and (1227- between δ(6.8-7.3) ppm assigned to 1258) cm-1 (C-N)str. Table (3) aromaticprotons. FT-IR spectrum of represent the physical data of compound (2) showed weak bands at -1 compounds(4a-4j).Characteristic bands 3078 cm for aromatic (C-H) str., -1 -1 -1 ofFT-IRspectra of compounds (4a- 2962 cm , 2931cm and 2877 cm 4j)are listed in Table (4). aliphatic (C-H)str. of (CH3) acetyl - Part Three group, strong bands at 1674 cm 1 -1 2-(1-phenylpyrazolin-3-yl) (C=O)str., two bands at 1558 cm and 1465 cm-1 aromatic system (C---- phenoxathiin derivatives(5a-5j) C)str. and 756 cm-1 (-----C-H) aromatic To a solution of 2-(3-phenyl-1- ring. The 1H-NMR spectrum showed a oxypropen-1-yl) phenoxathiin(3a) signal at δ 2.6 ppm assigned to the (1.65 g, 0.005 mol), phenyl hydrazine three protons of the acetyl group (0.830 g, 0.007mol) in ethanol (80 ml) andsignals between δ (7.0-7.3) ppm and few drops of piperidinewere assigned to aromaticprotons.Through refluxed for 3 hrs. On concentration nucleophilic addition reaction as the and cooling, gummy deposit separated typical reaction of aldehydes and out, this was crystallized from ketones, compound (2) undergoes the 407 Baghdad Science Journal Vol.10(2)2013 characteristic condensation reaction (3a-3j). The IR spectra of compounds with different kinds of aromatic (3a-3j) showed absorption bands aldehydes in ethanol instead of 1% at (1670-1648)cm-1 (C=O)str., NaOH solution as a catalyst to afford (1670-1685)cm-1 and (1600-1608)cm-1 aliphatic(C=C)str.The 1H-NMR cm-1and 2800 cm-1 aliphatic (C-H)str. spectrum showed a signal at δ 2.6 ppm Strong bands at 1665 cm-1 (C=O)str assigned to aliphatic three protons of and 1600 cm-1 (C=N)str, 1550 cm-1 methoxy group, signals between aromatic (C=C)str.Phenyl hydrazine δ(7.0-7.3) ppm assigned to both reacted with (3) in ethanol in presence olefinic H1 and H2 respectively and a of piperidine giving 2-phenyl signals at δ 7.5 ppm and δ 7.9 ppm pyrazoline(5a-5j). The structure of assigned to aromatic protons.The these compounds was established from additive property of the exocyclic IR and UV.FT-IR spectrum showed (C=C) in (3) conjugated with the reactivity medium weak bands at 3055 carbonyl group promoted us to cm-1 aromatic (C-H)str, 2975 cm-1 and investigate their behavior towards the 2865 cm-1 aliphatic (C-H)str.
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