ESTIMATION OF THE MELTING POINT OF RIGID ORGANIC COMPOUNDS (COSOLVENT, NAPHTHALENE).

Persistent Link:
http://hdl.handle.net/10150/183935
Title:
ESTIMATION OF THE MELTING POINT OF RIGID ORGANIC COMPOUNDS (COSOLVENT, NAPHTHALENE).
Author:
ABRAMOWITZ, ROBERT.
Issue Date:
1986
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The melting points of rigid, hydrogen bonding, and non-hydrogen bonding organic compounds have been estimated from their chemical structure. The estimation was accomplished through the use of both additive and non-additive non-constitutive properties of the molecule. The melting points of the aforementioned compounds can be estimated by the equation: TM = TMPN + TIHBN + TPACK + 8.9*EXPAN + 73.1*SIGMAL + 196.3 where the dependent variable, TM, is the melting point of the compound in Kelvin, SIGMAL is the logarithm of the symmetry number for the molecule, EXPAN is the eccentricity of the molecule taken to the third power, TMPN is the summation of the melting point number for each functional group in the molecule, TIHBN is the summation of an intramolecular hydrogen bonding index and TPACK is a packing efficiency index. The solubility of naphthalene in binary, ternary, and quinary cosolvent-water mixtures was determined by HPLC analysis. The samples were equilibrated for 48 hours on a test tube rotator, centrifuged, diluted with acetonitrile, and then injected onto a C8 10 micron column. The cosolvent mixtures used were hydro-organic solutions consisting of water with either methanol, ethanol, isopropanol, acetone, acetonitrile, propylene glycol or a combination of these as the cosolvent. The propylene glycol-water mixtures were allowed to equilibrate for 10 days. In all cases, naphthalene solubilities in binary cosolvent mixtures were found to obey log-linear relationships: log X = SIGMA(FRAC) - log X(w) where X is the mole fraction solubility of naphthalene in the mixture, X(w) is the mole fraction solubility in pure water, FRAC is the volume fraction of the cosolvent, and SIGMA is the slope. SIGMA can be estimated by using the UNIFAC method to predict the solubility in 100% cosolvent and by using the generalized solubility equation of Yalkowsky to estimate the water solubility. These binary equations can then be used to generate ternary and higher multicomponent equations.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Organic compounds -- Analysis.; Melting points.; Chemical structure.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Pharmaceutical Sciences; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Yalkowsky, Samuel H.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleESTIMATION OF THE MELTING POINT OF RIGID ORGANIC COMPOUNDS (COSOLVENT, NAPHTHALENE).en_US
dc.creatorABRAMOWITZ, ROBERT.en_US
dc.contributor.authorABRAMOWITZ, ROBERT.en_US
dc.date.issued1986en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe melting points of rigid, hydrogen bonding, and non-hydrogen bonding organic compounds have been estimated from their chemical structure. The estimation was accomplished through the use of both additive and non-additive non-constitutive properties of the molecule. The melting points of the aforementioned compounds can be estimated by the equation: TM = TMPN + TIHBN + TPACK + 8.9*EXPAN + 73.1*SIGMAL + 196.3 where the dependent variable, TM, is the melting point of the compound in Kelvin, SIGMAL is the logarithm of the symmetry number for the molecule, EXPAN is the eccentricity of the molecule taken to the third power, TMPN is the summation of the melting point number for each functional group in the molecule, TIHBN is the summation of an intramolecular hydrogen bonding index and TPACK is a packing efficiency index. The solubility of naphthalene in binary, ternary, and quinary cosolvent-water mixtures was determined by HPLC analysis. The samples were equilibrated for 48 hours on a test tube rotator, centrifuged, diluted with acetonitrile, and then injected onto a C8 10 micron column. The cosolvent mixtures used were hydro-organic solutions consisting of water with either methanol, ethanol, isopropanol, acetone, acetonitrile, propylene glycol or a combination of these as the cosolvent. The propylene glycol-water mixtures were allowed to equilibrate for 10 days. In all cases, naphthalene solubilities in binary cosolvent mixtures were found to obey log-linear relationships: log X = SIGMA(FRAC) - log X(w) where X is the mole fraction solubility of naphthalene in the mixture, X(w) is the mole fraction solubility in pure water, FRAC is the volume fraction of the cosolvent, and SIGMA is the slope. SIGMA can be estimated by using the UNIFAC method to predict the solubility in 100% cosolvent and by using the generalized solubility equation of Yalkowsky to estimate the water solubility. These binary equations can then be used to generate ternary and higher multicomponent equations.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectOrganic compounds -- Analysis.en_US
dc.subjectMelting points.en_US
dc.subjectChemical structure.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplinePharmaceutical Sciencesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorYalkowsky, Samuel H.en_US
dc.identifier.proquest8704753en_US
dc.identifier.oclc698224442en_US
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