researcharticle - hindawi publishing...

Hindawi Publishing CorporationJournal of CatalystsVolume 2013 Article ID 657409 4 pageshttpdxdoiorg1011552013657409

Research ArticleCatalytic Synthesis of Pyrazolo[34-d]pyrimidin-6-oland Pyrazolo[34-d]pyrimidine-6-thiol Derivatives UsingNanoparticles of NaX Zeolite as Green Catalyst

Ali Gharib12 Manouchehr Jahangir1 Mina Roshani1 Sara Moghadasi2 and Reza Safee2

1 Department of Chemistry Islamic Azad University Mashhad Iran2 Agricultural Researches and Services Center Mashhad Iran

Correspondence should be addressed to Ali Gharib organiccatalyst2008gmailcom

Received 12 August 2012 Revised 9 February 2013 Accepted 20 February 2013

Academic Editor Piyasan Praserthdam

Copyright copy 2013 Ali Gharib et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

An efficient and environmental benignmethod is reported for the synthesis of somepyrazolopyrimidine derivatives using 3-methyl-1-phenyl-5-pyrazolone with carbonyl compounds in the presence of nanozeolite Nax catalysts solvent-free and at reflux conditionsIt is noteworthy to mention that this method of the synthesis requires less time less temperature and better yield

1 Introduction

Pyrazolopyrimidine derivatives have received a great deal ofattention due to their pharmacological activities Pyrazolopy-rimidine derivatives have demonstrated promising antimi-crobial activity against gram-positive bacteria [1] Synthesisof such biologically important compounds assumes greatimportance Pyrazolopyrimidine derivatives are purine ana-logues and as such they have useful properties as antimetabo-lites in purine biochemical reaction [2] Moreover thesecompounds also display marked antitumor and antileukemicactivities [3] Pyrazolopyrimidine derivatives have received agreat deal of attention due to their pharmacological activity[4] such as allopurino [5] which is still the drug of choicefor the treatment of hyperuricemia and gouty arthritis [6]1-Phenyl-3-methyl-4-arylmethylene-5-pyrazolones are veryuseful intermediates in the synthesis of substituted pyra-zolones generally which were prepared by the condensationof 3-methyl-1-phenyl-5-pyrazolone with aromatic aldehydes[7] The incorporation of another heterocyclic moiety inpyrans either in the form of a substituent or as a fusedcomponent changes its properties and converts it into an alto-gether new and important heterocyclic derivative Pyrazoleshave attracted particular interest over the last few decades

due to the use of such ring system as the core nucleusin various drugs They are well known for their popularpharmacological activities Considering the importance ofpyrazolone derivatives it was thought worthwhile to syn-thesize new compounds incorporating both these moietiesAll the compounds synthesized in the present study werescreened for their antibacterial activity against some bacteria(both gram-negative and gram-positive) namely Escherichiacoli Pseudomonas aeruginosa Staphylococcus aureus Bacillussubtilis and C albicans by filter paper disc technique ZeoliteX is a highly versatilemolecular sieve from the faujasite familyof zeolites whose 74 A three-dimensional pore structureand solid acidity make it useful as a catalyst adsorbentmembrane and others [8ndash10] This type of zeolite is used forheavy metal adsorption [11] aromatics from aromaticalkanemixtures [12] andpara-xylene [13] separation aswell as natu-ral gas desulfurization [14] The powerful catalytic propertiesof X zeolite due to its use in the reaction between MeOHand PhNH

2[15] hydrocarbons cracking [16] chlorination of

toluene [17] and the ammonia synthesis [18] In this papernanozeolite NaX was synthesized via hydrothermal methodswith agitation and temperature controlling We did not usethe addition of organic templates directing agent seedingcrystals and other additives in this synthesis

2 Journal of Catalysts

Table 1 Synthesis of several pyrazolone-pyrimidine derivativesusing urea and nanoparticles of NaX zeolite catalyst

Entry Product Time (h) aYield () MP (∘C)1 4a -H 1 90 1852 4b 4-OH 15 955 1713 4c 3-OH 15 935 1564 4d 2-OH 15 91 1665 4e 4-Cl 25 84 1546 4f 3-Cl 25 80 1507 4g 4-CH3 1 92 1388 4h 4-OCH3 1 94 1459 4i 3-NO2 3 77 18810 4j 4-NO2 3 81 18311 4k 4-F 35 71 124aIsolated yield

2 Experimental

21 Chemicals and Apparatus All melting points are uncor-rected IR spectra were recorded in KBr discs using a Shi-madzu IR-740 spectrophotometer 1H- and 13C-NMR spectrawere recorded on a Bruker DPX 400MHz super-conductingNMR spectrometer with CDCl

3as a solvent and TMS as

an internal standard chemical shifts are reported in 120575 units(ppm) Mass spectra were measured on FABMS INCOS XLFinnigan MAT Microanalyses were performed on a LECO-CHNS-932 elemental analyzer

22 Nanozeolite NaX Synthesis The chemical reagents suchas fumed silica (7 nm Sigma-Alderich) NaOH (Merck Dar-mstadt Germany) and NaAlO

2(Sigma-Aldrich) were used

for zeolite synthesis The nanometer-sized faujasite-X zeolitewas synthesized by hydrothermal crystallization in a temper-ature-controlled shaker Aluminosilicate gel was preparedby mixing freshly prepared aluminate and silicate solutionstogether in themolar ratio 55Na

2O 10Al

2O3 40 SiO

2 190

H2O Typically an aluminosilicate gel containing 534 g of

NaOH 242 g of NaAlO2 343 g of SiO

2 and 500 g of H

2O

was adopted First a 250mL plastic bottle containing freshlyprepared sodium aluminate solution and SM-30 and fumedsilica the silicate sources were directly mixed with freshlyprepared aluminate solution at room temperature and thenimmediatelymoved to a shaker at the desired temperature forhydrothermal crystallization Hydrothermal crystallizationwas conducted at 60∘C for 4 days in a shaker with a rotationrate of 250 rpmThe powdered products were recovered withcentrifugation washed with DI water until pH lt 8 and thendried at room temperature for 24 h for further character-ization

23 Nanozeolite Characterization TheX-ray powder diffrac-tion (XRD) patterns were recorded at 25∘C on a Philipsinstrument (Xrsquopert diffractometer using CuK120572 radiation)with a scanning speed of 003∘ (2120579) minminus1 The crystallinityof sample was determined from the peak areas of 6∘ [18]16∘ [10] and 27∘ [13] and the average crystal dimension was

calculated using Scherrerrsquos equation [12 13] Also the particlesize distribution was measured by the Mastersizer 2000(Malvern instrument)The SEM (Hitachi model S-4160) wasused to particle size distribution of nanozeolite crystals andthe SiAl ratio elemental compositions of nanoparticles wasdetermined by XRF (Philips instrument)

24 Synthesis of Pyrazolone-Pyrimidine Derivatives Ureathiourea (001mol) 3-methyl-1-phenyl-5-pyrazolone (001mol) and various substituted aldehydes (001mol) were addednano zeolite NaX (002mol) The reaction mixture was ref-luxed for appropriate time the reaction was monitored bythin liquid chromatography Upon completion of the reactionthe clear solution thus obtained was treated with crushed iceto give the solid product which was filtered and dried Thecrude product was purified by recrystallization from ethanol(absolute ethanol)

25 Selected Spectra Data

Compound (4a) IR (KBr cmminus1) 3505 3422 3005 1634 15731H-NMR (400MHz CDCl

3 120575ppm) 853 (s 1H)488 (s 1H)

374 (m 8H) 228 (m 8H) 245 (s 3H)748 (m 9H) 13C-NMR (400MHz CDCl

3 120575ppm) 1631 1557 1437 1365

1296 1287 1282 1261 1207 1166 268 HRMS (EI) Calcdfor C18H17N4O [M]+ 3051003 Found 3051006 Anal Calcd

for C18H17N4O C 7082 H 560 N 1836 Found C 7088 H

552 N 1839

Compound (5a) IR (KBr cmminus1) 2552 3427 3005 1636 1575662 1H-NMR (400MHz CDCl

3 120575ppm) 854 (s 1H) 126

(m 1H) 373 (m 8H) 227 (m 8H) 236 (s 3H) 754 (m9H) 13C-NMR (400MHz CDCl

3 120575ppm) 1632 1557 1437

1365 1296 1289 1282 1261 1165 626 522 439 266HRMS (EI) Calcd for C

18H17N4S [M]+ 3211001 Found

3211008 Anal Calcd for C18H17N4S C 6725 H 537 N 1745

Found C 6729 H 541 N 1754

3 Results and Discussion

The preparation of the pyrazolone-pyrimidine derivativesinvolved the reaction of the respective ureathiourea 3-methyl-1-phenyl-5-pyrazolone with aromatic aldehydes byusing nanoparticles of NaX zeolite catalyst under solvent-freeand at reflux conditions (Scheme 1)

All the tested aromatic aldehydes bearing various sub-stituents such as chloro nitro methoxyl and other sub-stituents could successfully react with 3-methyl-1-phenyl-5-pyrazolone within 60ndash90 minutes with high yields Theresults were summarized in Tables 1 and 2

Interestingly we have not obtained the side productswhich were usually accompanied with the target compoundswhen the reaction was carried out in solvent-free The for-mation of the pyrazolopyrimidine system was unequivocallyestablished after analysis of NMR data of the productsThe chemical shifts and multiplicity of the protons were inconsonance with the expected values for example the protonat position 3 of all the compounds was found between 850and 907 ppm as a sharp singlet The XRD pattern matches

Journal of Catalysts 3

X

H2N NH2X = O S

NN

N

N N

N

NN

NN

O

CH3

CH3

CH3

H O

RR

R

Nanozeolite NaX catalystsolvent-free reflux

X = O

X = S

HO

HS

+ +

1 X= O S3andashk R= H 4-OH 3-OH 2-OH 4-Cl 3-Cl4-CH3 4-OCH3 3-NO2 4-NO2 4-F

1 2 3

4andashk

5andashk

Scheme 1 Synthesis of pyrazolone-pyrimidine derivatives by using nanoparticles of NaX Zeolite catalysts

5 10 15 20 25 30 35 40

Inte

nsity

(au

)

3000

2500

2000

1500

1000

500

2120579

XRD pattern of nanozeolite NaX

0

Figure 1 XRD pattern of as-synthesized sample crystallized

Figure 2 The FESEM image of nanozeolite NaX

very well with the simulated XRD powder pattern for FAUzeolite [12ndash16] indicating that the synthesized crystal is pureFAU zeolite and shows that nanozeolite NaX sample hasmorethan 95 crystalline (Figure 1)

The crystalline phase of aluminosilicate could be pro-duced NaX hydrate zeolite phase after left it in the suitabletemperature and time From the experimental results itcan be explained that the silica content in fly ash is notenough to form NaX hydrate zeolite phase after incubated

Table 2 Synthesis of several pyrazolone-pyrimidine derivativesusing thiourea and nanoparticles of NaX zeolite catalyst

Entry Product Time (min) aYield () MP (∘C)1 4a -H 1 91 1862 4b 4-OH 15 965 1803 4c 3-OH 15 93 1764 4d 2-OH 15 915 1845 4e 4-Cl 25 84 1816 4f 3-Cl 25 80 1857 4g 4-CH3 1 925 1828 4h 4-OCH3 1 95 2859 4i 3-NO2 3 76 21610 4j 4-NO2 3 815 22411 4k 4-F 35 72 151aIsolated yield

at 60∘C for 4 times 24 h Figure 1 showed that strong broad peaksof pure silica are centered range on asymp22-23∘ (2120579) which arein keeping with the strong broad peak of a characteristic ofamorphous SiO

2[19] The result showed that pure silica is in

an amorphous stateThe nanozeolite NaX is very hydrophilic with entrance

pores of approximately 74 A The particle size distributionsof nanozeolite crystal from dynamic light scattering (DLS)are shown in Figure 2 results indicated a narrow distributionof particle size with an average crystal size of 112 nm Theaverage crystal dimension of 105 plusmn 9 nm was calculated byScherrerrsquos equation from the diffraction peaks at 2120579 values of6∘ [18] 16∘ [10] and 27∘ [13]The average particle size (A) wascalculated by (1)

Scherrerrsquos equation is

119903 =119896120582

120573 cos 120579 (1)

where 119896 is the shape factor 120582 is the X-ray wavelengthtypically 154 A 120573 is the line broadening at half the maximumintensity (FWHM) in radians and 120579 is the Bragg angle


0 150 300 450 600

03

025

02

015

01

005

0

Volu

me (

)

Particle size (nm)

Figure 3 Distribution of particle size of nanozeolite NaX

The result of DLS is more important than XRD methodsbecause the DLS calculates the particle distribution but theScherrerrsquos equation measures an average particle size TheSEM image recorded for the as-synthesized nanozeolite sam-ple is shown in Figure 2 The Field-Emission Scanning Ele-ctron Microscope (FESEM) image recorded for the as-syn-thesized nanozeolite sample is shown in Figure 2 whichclearly indicates that the particle size of nano-NaX is ultrafineand within a range of 40ndash150 nm which is consistent with theresults calculated from the XRD pattern and dynamic lightscattering (Figure 3)

The particle size distributions of nanozeolite crystal fromdynamic light scattering (DLS) are shown in Figure 3 resultsindicated a narrow distribution of particle size with anaverage crystal size of 112 nm

Also the SiAl ratio of the nanoozeolite NaX was calcu-lated 125 through XRF analysis The unit cell mass of NaYzeolitewas calculated using the composition provided byXRFtest Na

106[(Al106

Si86O384

]

4 Conclusion

We have demonstrated that the reaction between 3-methyl-1-phenyl-5-pyrazolone with aldehydes and ureathiourea couldbe effectively performed in the presence of nanozeolite NaXcatalyst at reflux and solvent-free conditions The presentmethod has many obvious advantages over classical proce-dures including being environmentally more benign simplethe ease of product isolation higher yield shorter reactiontimes and the potential for recycling ionic liquid and catalystThe recyclability and reusability of the catalyst have beentestedThe new catalyst was inexpensive easy to prepare andstable It maintained its original activity during a period ofmore than a year that constituted this study

References

[1] B G Hildick and G Shaw ldquoPurines pyrimidines and imi-dazoles Part XXXVII Some new syntheses of pyrazolo[34-d]pyrimidines including allopurinolrdquo Journal of the ChemicalSociety C pp 1610ndash1613 1971

[2] E W Satherland G A Robinson and R W Butcher ldquoSomeaspects of the biological role of adenosine 3101584051015840-monophosphate(Cyclic AMP)rdquo Circulation vol 37 pp 279ndash306 1968

[3] R A Earl R J Pugmire G R Revankar and L B Townsend ldquoAchemical and carbon-13 nuclear magnetic resonance reinvesti-gation of the N-methyl isomers obtained by direct methylationof 5-amino-34-dicyanopyrazole and the synthesis of certainpyrazolo [34-d]pyrimidinesrdquo Journal of Organic Chemistry vol40 no 12 pp 1822ndash1828 1975

[4] D Villemin and B Labiad ldquoClay catalysis dry condensa-tion of 3-Methyl-1- Phenyl-5-Pyrazolone with aldehydes undermicrowave irradiationrdquo Synthetic Communications vol 20 pp3213ndash3220 1990

[5] T Welton ldquoRoom-temperature ionic liquids Solvents for syn-thesis and catalysisrdquo Chemical Reviews vol 99 no 8 pp 2071ndash2084 1999

[6] P Traxler G Bold J Frie M Lang N Lydon and H MettldquoSteroidal affinity labels of the estrogen receptor 3 Estradiol11120572-n-Alkyl derivatives bearing a terminal electrophilic groupantiestrogenic and cytotoxic propertiesrdquo Journal of MedicinalChemistry vol 40 pp 2217ndash2225 1997

[7] G Desimoni L Astolfi M Cambieri A Gamba and GTacconi ldquoHeterodiene syntheses-XIIThe conformational anal-ysis of cis and trans 2-alkoxy-4-phenyl-23-dihydropyran[23-c]pyrazoles steric interactions and the anomeric effectrdquo Tetrahe-dron vol 29 no 17 pp 2627ndash2634 1973

[8] S Sanga Z Liu P Tiana Z Liua L Qua and Y ZhangldquoSynthesis of small crystals zeolite NaYrdquo Materials Letters vol60 pp 1131ndash1131 2006

[9] B H Wang Y Y Xia S Y Zhuang Y H Zhang and T T YanThe Imaging Science Journal vol 25 pp 131ndash135 1998

[10] S Mintova and V Valtchev ldquoSynthesis of nanosized fau-typezeoliterdquo Studies in Surface Science andCatalysis vol 125 pp 141ndash148 1999

[11] Y S Ok J E Yang Y S Zhang S J Kim and D Y ChungldquoHeavy metal adsorption by a formulated zeolite-Portlandcement mixturerdquo Journal of Hazardous Materials vol 147 no1-2 pp 91ndash96 2007

[12] M Fathizadeh and M Nikazar ldquoAdsorption of aromatic fromalkanearomatic mixtures by NaY zeoliterdquo Journal of ChemicalEngineering of Japan vol 42 no 4 pp 241ndash247 2009

[13] C R Jacob S P Varkey and P Ratnasamy ldquoOxidation ofpara-xylene over zeolite-encapsulated copper and manganesecomplexesrdquo Applied Catalysis A vol 182 no 1 pp 91ndash96 1999

[14] MW Ackley S U Rege and H Saxena ldquoApplication of naturalzeolites in the purification and separation of gasesrdquoMicroporousand Mesoporous Materials vol 61 pp 25ndash42 2003

[15] L J Garces V D Makwana B Hincapie A Sacco and S LSuib ldquoSelective NN-methylation of aniline over cocrystallizedzeolites RHO and zeolite X (FAU) and over Linde type L (SrK-LTL)rdquo Journal of Catalysis vol 217 no 1 pp 107ndash116 2003

[16] F N Guerzoni and J Abbot ldquoCatalytic cracking of a binarymixture on zeolite catalystsrdquo Applied Catalysis A vol 103 no2 pp 243ndash258 1993

[17] M C Hausladen and C R F Lund ldquoZeolite-catalyzed chlori-nation of toluene by sulfuryl chloride activity selectivity anddeactivation of NaX and NaY zeolitesrdquo Applied Catalysis A vol190 no 1-2 pp 269ndash281 2000

[18] C T Fishel R J Davis and J M Garces ldquoAmmonia synthesiscatalyzed by ruthenium supported on basic zeolitesrdquo Journal ofCatalysis vol 163 no 1 pp 148ndash157 1996

[19] B W Jo C H Kim G H Tae and J B Park ldquoCharacteristicsof cement mortar with nano-SiO

2particlesrdquo Construction and

Building Materials vol 21 no 6 pp 1351ndash1355 2007

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Chromatography Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2013


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ISRN Chromatography


Hindawi Publishing Corporation httpwwwhindawicom Volume 2013Hindawi Publishing Corporation httpwwwhindawicom Volume 2013

The Scientific World Journal


Bioinorganic Chemistry and Applications


Journal of

SPECTROSCOPY

ISRN Analytical Chemistry


ElectrochemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2013


Advances in

Physical Chemistry

ISRN Physical Chemistry


SpectroscopyInternational Journal of


ISRN Inorganic Chemistry



Journal of

Chemistry


Inorganic Chemistry International Journal of


International Journal ofPhotoenergy


Analytical Methods in Chemistry

Journal of

Volume 2013

ISRN Organic Chemistry



CatalystsJournal of


Table 1 Synthesis of several pyrazolone-pyrimidine derivativesusing urea and nanoparticles of NaX zeolite catalyst

Entry Product Time (h) aYield () MP (∘C)1 4a -H 1 90 1852 4b 4-OH 15 955 1713 4c 3-OH 15 935 1564 4d 2-OH 15 91 1665 4e 4-Cl 25 84 1546 4f 3-Cl 25 80 1507 4g 4-CH3 1 92 1388 4h 4-OCH3 1 94 1459 4i 3-NO2 3 77 18810 4j 4-NO2 3 81 18311 4k 4-F 35 71 124aIsolated yield

2 Experimental

21 Chemicals and Apparatus All melting points are uncor-rected IR spectra were recorded in KBr discs using a Shi-madzu IR-740 spectrophotometer 1H- and 13C-NMR spectrawere recorded on a Bruker DPX 400MHz super-conductingNMR spectrometer with CDCl

3as a solvent and TMS as

an internal standard chemical shifts are reported in 120575 units(ppm) Mass spectra were measured on FABMS INCOS XLFinnigan MAT Microanalyses were performed on a LECO-CHNS-932 elemental analyzer

22 Nanozeolite NaX Synthesis The chemical reagents suchas fumed silica (7 nm Sigma-Alderich) NaOH (Merck Dar-mstadt Germany) and NaAlO

2(Sigma-Aldrich) were used

for zeolite synthesis The nanometer-sized faujasite-X zeolitewas synthesized by hydrothermal crystallization in a temper-ature-controlled shaker Aluminosilicate gel was preparedby mixing freshly prepared aluminate and silicate solutionstogether in themolar ratio 55Na

2O 10Al

2O3 40 SiO

2 190

H2O Typically an aluminosilicate gel containing 534 g of

NaOH 242 g of NaAlO2 343 g of SiO

2 and 500 g of H

2O

was adopted First a 250mL plastic bottle containing freshlyprepared sodium aluminate solution and SM-30 and fumedsilica the silicate sources were directly mixed with freshlyprepared aluminate solution at room temperature and thenimmediatelymoved to a shaker at the desired temperature forhydrothermal crystallization Hydrothermal crystallizationwas conducted at 60∘C for 4 days in a shaker with a rotationrate of 250 rpmThe powdered products were recovered withcentrifugation washed with DI water until pH lt 8 and thendried at room temperature for 24 h for further character-ization

23 Nanozeolite Characterization TheX-ray powder diffrac-tion (XRD) patterns were recorded at 25∘C on a Philipsinstrument (Xrsquopert diffractometer using CuK120572 radiation)with a scanning speed of 003∘ (2120579) minminus1 The crystallinityof sample was determined from the peak areas of 6∘ [18]16∘ [10] and 27∘ [13] and the average crystal dimension was

calculated using Scherrerrsquos equation [12 13] Also the particlesize distribution was measured by the Mastersizer 2000(Malvern instrument)The SEM (Hitachi model S-4160) wasused to particle size distribution of nanozeolite crystals andthe SiAl ratio elemental compositions of nanoparticles wasdetermined by XRF (Philips instrument)

24 Synthesis of Pyrazolone-Pyrimidine Derivatives Ureathiourea (001mol) 3-methyl-1-phenyl-5-pyrazolone (001mol) and various substituted aldehydes (001mol) were addednano zeolite NaX (002mol) The reaction mixture was ref-luxed for appropriate time the reaction was monitored bythin liquid chromatography Upon completion of the reactionthe clear solution thus obtained was treated with crushed iceto give the solid product which was filtered and dried Thecrude product was purified by recrystallization from ethanol(absolute ethanol)

25 Selected Spectra Data

Compound (4a) IR (KBr cmminus1) 3505 3422 3005 1634 15731H-NMR (400MHz CDCl

3 120575ppm) 853 (s 1H)488 (s 1H)

374 (m 8H) 228 (m 8H) 245 (s 3H)748 (m 9H) 13C-NMR (400MHz CDCl

3 120575ppm) 1631 1557 1437 1365

1296 1287 1282 1261 1207 1166 268 HRMS (EI) Calcdfor C18H17N4O [M]+ 3051003 Found 3051006 Anal Calcd

for C18H17N4O C 7082 H 560 N 1836 Found C 7088 H

552 N 1839

Compound (5a) IR (KBr cmminus1) 2552 3427 3005 1636 1575662 1H-NMR (400MHz CDCl

3 120575ppm) 854 (s 1H) 126

(m 1H) 373 (m 8H) 227 (m 8H) 236 (s 3H) 754 (m9H) 13C-NMR (400MHz CDCl

3 120575ppm) 1632 1557 1437

1365 1296 1289 1282 1261 1165 626 522 439 266HRMS (EI) Calcd for C

18H17N4S [M]+ 3211001 Found

3211008 Anal Calcd for C18H17N4S C 6725 H 537 N 1745

Found C 6729 H 541 N 1754

3 Results and Discussion

The preparation of the pyrazolone-pyrimidine derivativesinvolved the reaction of the respective ureathiourea 3-methyl-1-phenyl-5-pyrazolone with aromatic aldehydes byusing nanoparticles of NaX zeolite catalyst under solvent-freeand at reflux conditions (Scheme 1)

All the tested aromatic aldehydes bearing various sub-stituents such as chloro nitro methoxyl and other sub-stituents could successfully react with 3-methyl-1-phenyl-5-pyrazolone within 60ndash90 minutes with high yields Theresults were summarized in Tables 1 and 2

Interestingly we have not obtained the side productswhich were usually accompanied with the target compoundswhen the reaction was carried out in solvent-free The for-mation of the pyrazolopyrimidine system was unequivocallyestablished after analysis of NMR data of the productsThe chemical shifts and multiplicity of the protons were inconsonance with the expected values for example the protonat position 3 of all the compounds was found between 850and 907 ppm as a sharp singlet The XRD pattern matches


X

H2N NH2X = O S

NN

N

N N

N

NN

NN

O

CH3

CH3

CH3

H O

RR

R


X = O

X = S

HO

HS

+ +


1 2 3

4andashk

5andashk


5 10 15 20 25 30 35 40

Inte

nsity

(au

)

3000

2500

2000

1500

1000

500

2120579


0












119903 =119896120582

120573 cos 120579 (1)



0 150 300 450 600

03

025

02

015

01

005

0

Volu

me (

)

Particle size (nm)





106[(Al106

Si86O384

]

4 Conclusion


References































ISRN Chromatography







Journal of

SPECTROSCOPY






Advances in

Physical Chemistry








Journal of

Chemistry







Journal of

Volume 2013




CatalystsJournal of


X

H2N NH2X = O S

NN

N

N N

N

NN

NN

O

CH3

CH3

CH3

H O

RR

R


X = O

X = S

HO

HS

+ +


1 2 3

4andashk

5andashk


5 10 15 20 25 30 35 40

Inte

nsity

(au

)

3000

2500

2000

1500

1000

500

2120579


0












119903 =119896120582

120573 cos 120579 (1)



0 150 300 450 600

03

025

02

015

01

005

0

Volu

me (

)

Particle size (nm)





106[(Al106

Si86O384

]

4 Conclusion


References































ISRN Chromatography







Journal of

SPECTROSCOPY






Advances in

Physical Chemistry








Journal of

Chemistry







Journal of

Volume 2013




CatalystsJournal of


0 150 300 450 600

03

025

02

015

01

005

0

Volu

me (

)

Particle size (nm)





106[(Al106

Si86O384

]

4 Conclusion


References































ISRN Chromatography







Journal of

SPECTROSCOPY






Advances in

Physical Chemistry








Journal of

Chemistry







Journal of

Volume 2013




CatalystsJournal of










ISRN Chromatography







Journal of

SPECTROSCOPY






Advances in

Physical Chemistry








Journal of

Chemistry







Journal of

Volume 2013




CatalystsJournal of

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