Submit manuscript...
MOJ
eISSN: 2574-819X

Bioorganic & Organic Chemistry

Research Article Volume 2 Issue 2

Solubility of some novel cyanopyridine derivatives

Shipra Baluja, Jadgish Movalia

Department of Chemistry, Saurashtra University, India

Correspondence: Shipra Baluja, Department of Chemistry, Saurashtra University, Rajkot- 360 005, Gujarat, India

Received: April 03, 2018 | Published: April 16, 2018

Citation: Baluja S, Movalia J. Solubility of some novel cyanopyridine derivatives. MOJ Biorg Org Chem. 2018;2(2):112-117. DOI: 10.15406/mojboc.2018.02.00064

Download PDF

Abstract

Some new cyano pyridine derivatives have been synthesized and their characterization was done by IR, 1H NMR and mass spectral data. The solubility of these synthesized compounds has been studied in dimethyl formamide and dimethyl sulphoxide at different temperatures at atmospheric pressure.

Keywords: cyano pyridine derivative, solubility, DMF, DMSO, thermodynamic parameter

Abbreviations

DMF, dimethyl formamide; DMSO, dimethyl sulfoxide; RMSD, root-mean-square deviations; RD, relative deviations; RAD, relative average deviations

Introduction

Pyridine compounds exist in nature in various forms and are integral part of various natural products.1,2 The pyridine ring plays a key role in catalyzing both biological and chemical reactions.3 Various substituted pyridines demonstrate a wide range of applications. Among various substituted pyridines, cyano pyridine derivatives have been found to be an important sub class. Various substituted cyano pyridine derivatives are known to act as intermediates in the pharmaceutical, dye, photo and agrochemical industries.4‒6 Further, various cyano pyridines have drawn attention due to their wide spectrum biological activities.7‒11 Therefore, due to their applications in biological and chemical fields, it would be interesting to determine the solubility of some novel cyano pyridine derivatives in different solvents at various temperatures. The data may be useful for their application in other fields also.

Thus, in the present work, solubility of some newly synthesized cyano pyridine derivatives is determined in dimethyl formamide and dimethyl sulfoxide at different temperatures. Further, some thermodynamic parameters such as enthalpy, Gibb’s free energy and entropy of dissolution for these synthesized compounds have also been evaluated.

Experimental

The solvents dimethyl formamide (DMF) and dimethyl sulfoxide (DMSO) were used for the present study were purified by standard methods.12 All the synthesized compounds were crystallized and Figure 1 shows the general structure of these derivatives.

Figure 1 Asymmetric oxidation of the thioethers.

Solubility

The gravimetric method was used to study the solubility. An excess mass of compound was added to a known mass of solvent. The solution was heated to a constant temperature with continuous stirring. After, at least 3hrs the stirring was stopped and the solution was kept at a constant temperature for 2hrs. A portion of this solution was filtered and by a preheated injector, 5ml of this clear solution was taken to pre weighted measuring vial (m0). The vial was quickly and tightly closed and weighted (m1) to determine the mass of the sample (m1- m0). To prevent dust contamination, the vial was covered with a piece of filter paper. After completely dryness of vial mass, the vial was reweighed (m2) to determine the mass of the constant residue solid (m2- m0). All the weights taken using Mettler Toledo AB204-S, Switzerland electronic balance with uncertainty of ±0.0001g. Thus the concentration of solid sample in the solution, mole fraction x, could be determined from equation

x= (m2m0)/M1 (m2m0)/M1+(m1m2)/M2 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcfaOaamiEai abg2da9maalaaabaGaaiikaiaad2gajuaicaaIYaqcfaOaeyOeI0Ia amyBaKqbGiaaicdajuaGcaGGPaGaai4laiaad2eajuaicaaIXaaaju aGbaGaaiikaiaad2gajuaicaaIYaqcfaOaeyOeI0IaamyBaKqbGiaa icdajuaGcaGGPaGaai4laiaad2eajuaicaaIXaqcfaOaey4kaSIaai ikaiaad2gajuaicaaIXaqcfaOaeyOeI0IaamyBaKqbGiaaikdajuaG caGGPaGaai4laiaad2eajuaicaaIYaaaaaaa@5729@ …………….. (1)

Where M1 and M2 is the molar mass of solvent and compound respectively. At each temperature, the measurement was repeated three times and an average value is taken.

Results and discussion

The molecular formula, molecular weight, melting point, % yield and Rf values along with the solvent systems of all the compounds are given in Table 1.

Sr. No

Comp. code

Mol. Wt. g/mol)

M.F.

R

Rf* Value

M.P. ºC

Yield %

 
 

1

CP-1

436.8

C27H17ClN4O

4-OCH3-C6H4-

0.59

221

70

 

2

CP -2

420.8

C26H17ClN4

4-CH3-C6H4-

0.56

180

68

 

3

CP -3

485.7

C25H14BrClN4

4-Br-C6H4-

0.63

214

71

 

4

CP -4

421.8

C25H16ClN5

4-NH2-C6H4-

0.69

208

65

 

5

CP -5

451.8

C25H14ClN5O2

4-NO2-C6H4-

0.64

187

69

 

6

CP -6

422.8

C25H15ClN4O

3-OH-C6H4-

0.7

235

67

 

7

CP -7

441.3

C25H14Cl2N4

4-Cl-C6H4-

0.72

234

72

 

8

CP -8

451.8

C25H14ClN5O2

3-NO2-C6H4-

0.62

201

63

 

9

CP -9

422.8

C25H15ClN4O

4-OH-C6H4-

0.67

229

65

 

10

CP -10

406.8

C25H15ClN4

H-C6H4-

0.49

162

73

 

Table 1 Physical constant of Cyano pyridine compounds

Figure 2 The variation of experimental mole fraction solubility (x) of compounds with temperature in DMF.

(♦); CP-1, (■); CP-2, (▲); CP-4, (♦); CP-4, (); CP-5, (♦); CP-6, (■); CP-7, (▲); CP-8, (); CP-9, (); CP-10.

Figure 3 The variation of experimental mole fraction solubility (x) of compounds with temperature in DMSO.
(♦); CP-1, (■); CP-2, (▲); CP-4, (♦); CP-4, (); CP-5, (♦); CP-6, (■); CP-7, (▲); CP-8, (); CP-9, (); CP-10.

Table 2 and Table 3 show the experimental solubility values of compounds at different temperatures in DMF and DMSO respectively. The variation of mole fraction solubility of compounds with temperature in DMF and DMSO is shown in Figure 2 and Figure 3 respectively. It is observed that in both the solvents, solubility increases with temperature. Further, comparison of solubility in both the solvents; DMF and DMSO shows that overall solubility is greater in DMSO than that in DMF. Thus, the solvent polarity plays an important role on the solubility of studied compounds. The dielectric constant of DMSO (46.6) is greater than that of DMF (36.71). However, there is very small variation is in their dipole moments (3.9 for DMSO and 3.86 for DMF). This suggests that dielectric constant of solvent plays an important role in dissolution for the studied compounds.
The temperature dependence of solubility was described by the modified Apelblat equation13,14

Temp.K

x

xc

100 RD

x

xc

100 RD

 

CP-1

CP-6

298.15

0.0049

0.004873

0.553

0.0081

0.008117

-0.2144

303.15

0.0055

0.005593

-1.6838

0.0092

0.00915

0.5447

308.15

0.0069

0.006858

0.6078

0.0103

0.010427

-1.2285

313.15

0.009

0.008947

0.5884

0.0121

0.012002

0.8086

318.15

0.0123

0.012368

-0.5563

0.0139

0.013947

-0.3354

 

CP-2

CP-7

298.15

0.0044

0.004415

-0.3523

0.004

0.004012

-0.2966

303.15

0.0054

0.005367

0.6156

0.0055

0.005488

0.2174

308.15

0.0063

0.006343

-0.6819

0.0071

0.007087

0.1892

313.15

0.0073

0.007302

-0.0298

0.0086

0.008668

-0.7937

318.15

0.0082

0.008201

-0.0139

0.0101

0.010077

0.2285

 

CP-3

CP-8

298.15

0.0065

0.0065

0.0051

0.0074

0.007406

-0.0775

303.15

0.0081

0.008141

-0.5025

0.0094

0.009446

-0.4843

308.15

0.0098

0.00974

0.6075

0.0115

0.011371

1.1229

313.15

0.0111

0.011165

-0.5862

0.0128

0.012966

-1.2995

318.15

0.0123

0.012292

0.061

0.0141

0.014052

0.3405

 

CP-4

CP-9

298.15

0.0049

0.004919

-0.3924

0.0086

0.008626

-0.3023

303.15

0.0061

0.006049

0.8295

0.0104

0.010358

0.4006

308.15

0.0072

0.007277

-1.0755

0.0121

0.012125

-0.2068

313.15

0.0086

0.008575

0.285

0.0138

0.013857

-0.4096

318.15

0.0099

0.00991

-0.102

0.0155

0.015482

0.1165

 

CP-5

CP-10

298.15

0.008

0.008006

-0.0787

0.0075

0.007506

-0.0787

303.15

0.0101

0.010167

-0.6589

0.0095

0.009547

-0.4976

308.15

0.0123

0.012098

1.6408

0.0116

0.011471

1.1087

313.15

0.0133

0.013546

-1.851

0.0129

0.013066

-1.2862

318.15

0.0144

0.014325

0.5219

0.0142

0.014154

0.3261

Table 2 The experimental solubility (x), calculated solubility (xc) and relative deviation (RD) of anopyridines derivatives in DMF at different temperatures.

lnx=A+ B T + ClnT MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcfaieaaaaaa aaa8qaciGGSbGaaiOBaiaadIhacqGH9aqpcaWGbbGaey4kaSYaaSaa a8aabaWdbiaadkeaa8aabaWdbiaadsfaaaGaey4kaSIaaiiOaiaado eaciGGSbGaaiOBaiaadsfaaaa@43AD@ ….. (2)

Where T is the absolute temperature, and A, B, and C are empirical constants. The values of these parameters are listed in Table 4. The root-mean-square deviations (RMSD) are calculated using the following equation:

RMSD= i=1 N ( x i x ) 2  N1 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcfaieaaaaaa aaa8qacaqGsbGaaeytaiaabofacaqGebGaeyypa0ZaaOaaa8aabaWd bmaawahabeqcfaYdaeaapeGaamyAaiabg2da9iaaigdaa8aabaWdbi aad6eaaKqba+aabaWdbiabggHiLdaadaWcaaWdaeaapeWaaeWaa8aa baWdbiaadIhapaWaaSbaaKqbGeaapeGaamyAaaqcfa4daeqaa8qacq GHsislcaWG4baacaGLOaGaayzkaaWdamaaCaaabeqcfasaa8qacaaI YaGaaiiOaaaaaKqba+aabaWdbiaad6eacqGHsislcaaIXaaaaaqaba aaaa@4E27@ …….. (3)

Where N is the number of experimental points and x and xi represent the mole fraction solubility of the experiment and that calculated from eq 2, respectively. These values are given in Table 4. Further, relative deviations (RD) and relative average deviations (RAD) are calculated by eq (4) and (5).

RD=( x x i x ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcfaieaaaaaa aaa8qacaWGsbGaamiraiabg2da9maabmaapaqaa8qadaWcaaWdaeaa peGaamiEaiabgkHiTiaadIhapaWaaSbaaKqbGeaapeGaamyAaaqcfa 4daeqaaaqaa8qacaWG4baaaaGaayjkaiaawMcaaaaa@410F@

RAD= 1 N i N ( x x i ) x MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcfaieaaaaaa aaa8qacaqGsbGaaeyqaiaabseacqGH9aqpdaWcaaWdaeaapeGaaGym aaWdaeaapeGaamOtaaaadaGfWbqabKqbG8aabaWdbiaadMgaa8aaba Wdbiaad6eaaKqba+aabaWdbiabggHiLdaadaWcaaWdaeaapeWaaeqa a8aabaWdbiaadIhaaiaawIcaaiabgkHiTmaabiaapaqaa8qacaWG4b WdamaaBaaajuaibaWdbiaadMgaaKqba+aabeaaa8qacaGLPaaaa8aa baWdbiaadIhaaaaaaa@48FA@ …… (5)

Where N is the number of experimental points and xi is the solubility calculated by eq 2. The values of relative deviation are listed in Table 2 and Table 3 for DMF and DMSO respectively and relative average deviation values are reported in Table 4. It is evident from Table 2 and Table 3 that relative deviation (RD) values are not more than 1.85% for DMF and 2.86% for DMSO. Thus, there is good agreement between experimental and calculated solubility values in both the solvents. Using experimental data of solubility in different solvents, some thermodynamic parameters such as dissolution enthalpy, Gibb’s energy of dissolution and entropy have also been evaluated. According to modified Van’t Hoff equation15,16 the dissolution enthalpy  were evaluated by following relation.

lnx ( 1 T 1 T hm ) = Δ H sol R MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcfaieaaaaaa aaa8qadaWcaaWdaeaapeGaeyOaIyRaamiBaiaad6gacaWG4baapaqa a8qacqGHciITdaqadaWdaeaapeWaaSaaa8aabaWdbiaaigdaa8aaba WdbiaadsfaaaGaeyOeI0YaaSaaa8aabaWdbiaaigdaa8aabaWdbiaa dsfapaWaaSbaaKqbGeaapeGaamiAaiaad2gaaKqba+aabeaaaaaape GaayjkaiaawMcaaaaacqGH9aqpcqGHsisldaWcaaWdaeaapeGaeuiL dqKaamisa8aadaWgaaqcfasaa8qacaWGZbGaam4BaiaadYgaa8aabe aaaKqbagaapeGaamOuaaaaaaa@4F17@ ….. (6)

Where T is the experimental temperature and R is universal gas constant. Thm represent the mean harmonic temperature which is given as

T hm = n i n ( 1 T ) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcfaieaaaaaa aaa8qacaWGubWdamaaBaaajuaibaWdbiaadIgacaWGTbaajuaGpaqa baWdbiabg2da9maalaaapaqaa8qacaWGUbaapaqaa8qadaqfWaqabK qbG8aabaWdbiaadMgaa8aabaWdbiaad6gaaKqba+aabaWdbiabggHi LdaadaqadaWdaeaapeWaaSaaa8aabaWdbiaaigdaa8aabaWdbiaads faaaaacaGLOaGaayzkaaaaaaaa@4534@ ….. (7

Where n is the number of experimental temperatures.17 In present case, the value of Thm is obtained only 308K. The slope of the plot of ln x versus (1/T-1/308) gives the value of ∆Hsol. From the intercepts of these plots, Gibbs energy change (ΔGsol) for dissolution process were calculated from the following relation15

Δ G sol =R T hm .intercept MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcfaieaaaaaa aaa8qacqqHuoarcaWGhbWdamaaBaaajuaibaWdbiaadohacaWGVbGa amiBaaqcfa4daeqaa8qacqGH9aqpcqGHsislcaWGsbGaamiva8aada Wgaaqcfasaa8qacaWGObGaamyBaaWdaeqaaKqba+qacaGGUaGaamyA aiaad6gacaWG0bGaamyzaiaadkhacaWGJbGaamyzaiaadchacaWG0b aaaa@4C99@ ….. (8)

Using these evaluated ∆Hsol and ∆Gsol values, the entropies of solutions ∆Ssol were obtained from the following equation:

Δ S sol = Δ H sol Δ G sol T hm MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcfaieaaaaaa aaa8qacqqHuoarcaWGtbWdamaaBaaajuaibaWdbiaadohacaWGVbGa amiBaaqcfa4daeqaa8qacqGH9aqpdaWcaaWdaeaapeGaeuiLdqKaam isa8aadaWgaaqcfasaa8qacaWGZbGaam4BaiaadYgaaKqba+aabeaa peGaeyOeI0IaeuiLdqKaam4ra8aadaWgaaqcfasaa8qacaWGZbGaam 4BaiaadYgaa8aabeaaaKqbagaapeGaamiva8aadaWgaaqcfasaa8qa caWGObGaamyBaaqcfa4daeqaaaaaaaa@4F15@ ….. (9)

Temp.K

x

xc

100 RD

x

xc

100 RD

 

CP-1

CP-6

298.15

0.0049

0.004919

-0.3816

0.0082

0.008206

-0.0724

303.15

0.0063

0.006213

1.3771

0.0095

0.009474

0.2704

308.15

0.0077

0.007921

-2.8667

0.0108

0.01089

-0.8342

313.15

0.0104

0.010183

2.0845

0.0125

0.012464

0.2849

318.15

0.0131

0.013194

-0.7213

0.0142

0.014209

-0.0606

 

CP-2

CP-7

298.15

0.006

0.005988

0.193

0.0045

0.004508

-0.1743

303.15

0.0066

0.006571

0.4398

0.0059

0.005902

-0.038

308.15

0.0071

0.007189

-1.259

0.0074

0.007384

0.2207

313.15

0.0078

0.007844

-0.5691

0.0088

0.00885

-0.5667

318.15

0.0086

0.008537

0.737

0.0102

0.010189

0.1077

 

CP-3

CP-8

298.15

0.0066

0.006601

-0.0213

0.0076

0.007617

-0.2262

303.15

0.0081

0.008119

-0.2378

0.0096

0.00961

-0.1085

308.15

0.0097

0.009706

-0.058

0.0115

0.011402

0.8531

313.15

0.0113

0.011295

0.0408

0.0126

0.012769

-1.3403

318.15

0.0128

0.012819

-0.1456

0.0136

0.013546

0.3978

 

CP-4

CP-9

298.15

0.005

0.005014

-0.2731

0.0085

0.008526

-0.3015

303.15

0.0064

0.006414

-0.2132

0.0104

0.010368

0.3039

308.15

0.0078

0.007689

1.4236

0.0122

0.012193

0.0572

313.15

0.0085

0.008673

-2.0393

0.0138

0.013894

-0.6778

318.15

0.0093

0.00924

0.6421

0.0154

0.015369

0.202

 

CP-5

CP-10

298.15

0.0081

0.008122

-0.2738

0.0075

0.007495

0.0622

303.15

0.0102

0.010198

0.0151

0.009

0.009075

-0.8341

308.15

0.0122

0.012095

0.864

0.0106

0.010466

1.2654

313.15

0.0134

0.013595

-1.4544

0.0114

0.011531

-1.1507

318.15

0.0146

0.014532

0.4683

0.0122

0.012172

0.2297

Table 3 The experimental solubility (x), calculated solubility (xc) and relative deviation (RD) of cyanopyridines derivatives in DMSO at different temperatures.

Compounds

A

B

C

γ

105 rmsd

102 RAD

 

DMSO

CP-1

-1768.58

76932.79

254.9775

0.989

17.7

-0.1127

CP-2

548.9647

-27851

-80.907

0.9998

2.83

-0.0925

CP-3

971.1418

-47221.7

-143.534

0.9998

4.87

-0.083

CP-4

390.0745

-20902.7

-57.0911

0.9997

4.91

-0.0911

CP-5

1442.436

-68552.3

-213.658

0.9985

16.69

-0.0852

CP-6

-367.517

14421.11

55.16949

0.9993

8.74

-0.085

CP-7

1204.318

-59051.6

-177.58

0.9999

3.78

-0.0911

CP-8

1259.862

-60438.5

-186.404

0.9994

11.04

-0.0796

CP-9

497.3518

-25321.4

-73.2199

0.9999

4.05

-0.0803

CP-10

1241.621

-59578.3

-183.707

0.9994

11.01

-0.0856

 

DMSO

CP-1

-410.769

-14588

62.57469

0.9988

16.77

-0.1016

CP-2

-2.57231

-1540.24

0.459747

0.9984

6.11

-0.0917

CP-3

553.1926

-28204.6

-81.3703

0.9999

1.39

-0.0844

CP-4

1435.946

-68395.8

-212.693

0.9987

10.76

-0.092

CP-5

1255.235

-59986.6

-185.842

0.9993

11.65

-0.0762

CP-6

-1.28015

-2365.81

0.774249

0.9998

5.04

-0.0824

CP-8

1361.631

-64833.1

-201.674

0.9994

10.18

-0.0848

CP-9

689.6105

-34135.8

-101.777

0.9999

5.34

-0.0832

CP-10

1070.677

-51157.2

-158.662

0.9988

10.2

-0.0855

Table 4 Coefficients A, B and C of equation 2, relative average deviation (RAD) and root mean square deviation (rmsd) of cyanopyridine derivatives in DMF and DMSO.

All these thermodynamic parameters are listed in Table 5.

Comp.code

ΔHsol kJ.mol-1

ΔGsol kJ.mol-1

ΔSsol J.mol-1.K-1

ΔHsol kJ.mol-1

ΔGsol kJ.mol-1

ΔSsol J.mol-1.K-1

 

DMF

DMSO

CP-1

39.01

12.63

85.64

39.15

12.37

86.94

CP -2

24.25

13.02

36.47

13.88

12.65

41

CP -3

25.33

11.97

43.38

26.4

11.94

46.94

CP -4

27.5

12.65

48.19

23.91

12.62

36.65

CP -5

22.75

11.46

36.65

22.71

11.44

36.58

CP -6

21.18

11.66

30.93

21.47

11.59

32.08

CP -7

36.22

12.81

75.98

32.59

12.69

64.64

CP -8

25.46

11.6

44.98

22.98

11.61

36.91

CP -9

22.85

11.36

37.32

23.23

11.36

38.52

CP -10

25.11

11.58

43.92

19.08

11.8

23.66

Table 5 Thermodynamic parameters of dissolution of compounds in DMF and DMSO.

It is evident from Table 5, that for all the compounds, the evaluated thermodynamic parameters i.e., ∆Hsol, ∆Gsol and ∆Ssol values are positive for both the solvents. The positive ∆Hsol suggests endothermic dissolution of compounds in both the solvents. The endothermic effect may be due to strong interactions between compound and solvent molecules.17,18 Whereas, positive ∆Gsol values indicate that the dissolution process is spontaneous. The positive entropy indicates that dissolution process increases the randomness in solution.18 However, for some compounds entropy is less than half value than those of other compounds. This depends on the functional groups present in the compound as well as on the solvent. Different functional groups interact differently with the solvent, so randomness will be different.

Conclusion

It is concluded that solubility increases with temperature in both the solvents. Overall, solubility is greater in DMSO than that in DMF for all the compounds. Further, the evaluated thermodynamic parameters i.e., enthalpy, Gibb’s free energy and entropy of dissolutions values are positive for both the solvents. The positive enthalpy suggests endothermic dissolution of compounds in both the solvents indicating thereby strong interactions between compound and solvent molecules. The positive Gibb’s free energy and entropy indicate that dissolution process is spontaneous and it increases the randomness in solution.

Acknowledgements

Authors are thankful to Head of Chemistry Department, Saurashtra University, Rajkot, India for providing necessary facilities.

Conflict of interest

There is no conflict of interest.

References

  1. Scriven EVF. Pyridines: from Lab to Production, Ist ed. Amsterdam: Elsevier; 2013.
  2. Schlosser M, Mongin F. Pyridine elaboration through organometallic intermediates: region chemical control and completeness. Chem Soc Rev. 2007;36(7):1161‒1172.
  3. Chaubey A, Pandaya SN. Pyridine: A versatile nuclease in pharmaceutical field. Asian J Pharma Clin Res. 2011;4(4):5‒8.
  4. You J, Lai SL, Liu W, et al. Bipolar cyano-substituted pyridine derivatives for applications in organic light-emitting devices. J Mater Chem. 2012;22(18):8922‒8929.
  5. Oganisyan S, Noravyan AS, Grigoryan MZ. Condensed pyrido-pyrimidines.7. Synthesis of condensed triazolo[4,3-c]- and tetrazolo[1,5-] pyrimidnes. Chem Heterocyclic Compds. 2004;40(1):75‒78.
  6. Bowman MD, Jacobson MM, Blackwell HE. Discovery of Fluorescent Cyanopyridine and Deazalumazine Dyes Using Small Molecule Macroarrays. Org Lett. 2006;8(8):1645–1648.
  7. Bernardino MR, LC da S Pinheiro PG, Rodrigues CR, et al. Design, synthesis, SAR, and biological evaluation of new 4-(phenylamino)thieno[2,3-b] pyridine derivatives. Bioorg Med Chem. 2006;14(16):5765‒5770.
  8. Márquez MJ, Márquez MB, Cataldo PG, et al. A Comparative Study on the Structural and Vibrational Properties of Two Potential Antimicrobial and Anticancer Cyanopyridine Derivatives. Open J Syn Theory Appl. 2015;4(1):1‒19.
  9. Saad HA, Mokbil MN, El-Gendy AM, et al. Synthesis of some glycosides of pyridinone derivatives. Synth Commun. 2002;32(8):1189‒1195.
  10. Dolle V, Fan E, Nguyen CH, et al. A new series of pyridinone derivatives as potent non-nucleoside human immuno deficiency virus type 1 specific reverse transcriptase inhibitors. J Med Chem. 1995;38(23):4679‒4686.
  11. Sondhi SM, Jain S, Dinodia M, et al. Synthesis of some thiophenes, imidazole and pyridine derivatives exhibiting good anti-inflammatory and analgesic activities. Med Chem. 2008;4(2):146‒154.
  12. Riddick JA, Bunger WB, Sakano TK. Organic Solvents-Physical Properties and Methods of Purification. 4th ed. Techniques of Chemistry. New Jersey: John Wiley; 1986. p. 1131‒1294.
  13. Hao HX, Wang JK, Wang YL. Solubility of dexamethasonesodium phosphate in different solvents. J Chem Eng Data. 2004;49(6):1697−1698.
  14. Nie Q, Wang JK, Wang YL. Solubility of 11α-hydroxy-16α, 17α Eepoxyprogestrone in different solvents between 283 and 323K. J Chem Eng Data. 2005;50:989−992.
  15. Krug RR, Hunter WG, Grieger RA. Enthalpy entropy compensation. 2. Separation of the Chemical from the Statistical Effects. J Phys Chem. 1976;80(21):2341‒2351.
  16. Bustamante SP, Romero AP, Escalera B, et al. Nonlinear enthalpy-Entropy Compensation for the Solubility of Drugs in Solvent Mixtures: Paracetamol, Acetanilide and Nalidixic acid in dioxane-water. J Pharma Sci. 1998;87(12):1590‒1596.
  17. Aragon DM, Ruidiaz MA, Vargas EF, et al. Solubility of the Antimicrobial Agent Triclosan in Organic Solvents of Different Hydrogen Bonding Capabilities at Several Temperatures. J Chem Eng Data. 2008;53(11):2576‒2580.
  18. Kalsi PS. Organic reactions and their mechanisms. 2nd ed. New Delhi: New age international (P) limited; 2004. p. 119.
Creative Commons Attribution License

©2018 Baluja, et al. This is an open access article distributed under the terms of the, which permits unrestricted use, distribution, and build upon your work non-commercially.