Persistent Link:
http://hdl.handle.net/10150/193516
Title:
Estimation of Melting Points of Organic Compounds
Author:
Jain, Akash
Issue Date:
2005
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:
Melting point finds applications in chemical identification, purification and in the calculation of a number of other physicochemical properties such as vapor pressure and aqueous solubility. Despite the availability of enormous amounts of experimental data, no generally applicable methods have been developed to estimate the melting point of a compound from its chemical structure. A quick estimation of melting point can be a useful tool in the design of new chemical entities.In this dissertation, a simple means of estimating the melting points for a large variety of pharmaceutically and environmentally relevant organic compounds is developed. Melting points are predicted from the separate calculation of the enthalpy and entropy of melting directly from the chemical structure. The entropy of melting is calculated using a semi-empirical equation based on only two non-additive molecular parameters. This equation is validated and refined using a large collection of experimental entropy of melting values. The enthalpy of melting is calculated by additive group contributions.Melting points are estimated from the ratio of the enthalpy of melting and the entropy of melting. All of the methods and group contributions developed in this study are compatible with the UPPER (Unified Physical Property Estimating Relationships) scheme. The predicted melting points are compared to experimental melting points for over 2200 organic compounds collected from the literature. The average absolute error in melting point prediction is 30.1 °. This is a very reasonable estimate considering the size and diversity of the dataset used in this study.
Type:
text; Electronic Dissertation
Keywords:
Melting Point; Enthalpy; Entropy; Group Contribution; Symmetry; Flexibility
Degree Name:
PhD
Degree Level:
doctoral
Degree Program:
Pharmaceutical Sciences; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Yalkowsky, Samuel H
Committee Chair:
Yalkowsky, Samuel H

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleEstimation of Melting Points of Organic Compoundsen_US
dc.creatorJain, Akashen_US
dc.contributor.authorJain, Akashen_US
dc.date.issued2005en_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.abstractMelting point finds applications in chemical identification, purification and in the calculation of a number of other physicochemical properties such as vapor pressure and aqueous solubility. Despite the availability of enormous amounts of experimental data, no generally applicable methods have been developed to estimate the melting point of a compound from its chemical structure. A quick estimation of melting point can be a useful tool in the design of new chemical entities.In this dissertation, a simple means of estimating the melting points for a large variety of pharmaceutically and environmentally relevant organic compounds is developed. Melting points are predicted from the separate calculation of the enthalpy and entropy of melting directly from the chemical structure. The entropy of melting is calculated using a semi-empirical equation based on only two non-additive molecular parameters. This equation is validated and refined using a large collection of experimental entropy of melting values. The enthalpy of melting is calculated by additive group contributions.Melting points are estimated from the ratio of the enthalpy of melting and the entropy of melting. All of the methods and group contributions developed in this study are compatible with the UPPER (Unified Physical Property Estimating Relationships) scheme. The predicted melting points are compared to experimental melting points for over 2200 organic compounds collected from the literature. The average absolute error in melting point prediction is 30.1 °. This is a very reasonable estimate considering the size and diversity of the dataset used in this study.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectMelting Pointen_US
dc.subjectEnthalpyen_US
dc.subjectEntropyen_US
dc.subjectGroup Contributionen_US
dc.subjectSymmetryen_US
dc.subjectFlexibilityen_US
thesis.degree.namePhDen_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 Hen_US
dc.contributor.chairYalkowsky, Samuel Hen_US
dc.contributor.committeememberYalkowsky, Samuel H.en_US
dc.contributor.committeememberMayersohn, Michaelen_US
dc.contributor.committeememberMyrdal, Paul B.en_US
dc.contributor.committeememberRaghavan, Srinien_US
dc.identifier.proquest1303en_US
dc.identifier.oclc137354912en_US
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