Date of Award

January 2012

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Chemistry

First Advisor

Qianli Chu

Abstract

Recent decades have witnessed the discovery of a wide variety of nanomaterials. These nanomaterials vary from zero-dimensional nanodots to three-dimensional nanoflowers. However the properties of these nanomaterials have not been fully explored. A majority of the nonmaterials discovered so far are inorganic. There is little information about nanomaterials which are entirely based on organic compounds. Therefore this thesis focuses on the synthesis of two-dimensional nanosheets based on organic frameworks.

In this study, a number of two-armed and three-armed carboxamides and carbamates have been synthesized, characterized and self-assembly process was studied. The self-assembly of these amides and carbamates were studied in a large number of single solvents as well as combination of solvents. Two-armed amides and carbamates having aromatic cores are found to have poor solubility in all but DMF and DMSO. The two-armed amides and carbamates having linker alkyl chain are found to have good solubility and crystal formation in a few solvents, but the quality of the crystal is not good enough for the XRD analysis.

The polar solvents along with a trace amount of water are found to be more effective in getting perfect crystals of three-armed carbamates for X-ray crystallography. Carbamates with side-arms of three carbons and a cyclohexyl ring form perfect quality

crystals in EtOAc, MeCN, and THF:H2O. In the process of growing single crystal several crystallization techniques were used. Slow evaporation process is found to be more efficient in getting good quality crystal.

The crystal structures of carbamates have been determined as a part of the project .The morphology of the nanosheets was also studied by the transmission electron microscope (TEM). The TEM image of the carbamates reveals that its morphology is two-dimensional sheet. Additionally, data from powdered XRD have also revealed the formation of same or similar crystalline isoform from a variety of conditions.

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