Download I. Synthesis of Ascarosides for Biological Evaluation and II. Development of Visible Light-Promoted PDF

TitleI. Synthesis of Ascarosides for Biological Evaluation and II. Development of Visible Light-Promoted
LanguageEnglish
File Size7.9 MB
Total Pages216
Table of Contents
                            Louisiana State University
LSU Digital Commons
	2015
I. Synthesis of Ascarosides for Biological Evaluation and II. Development of Visible Light-Promoted Selenofunctionalization and Grafting of Aryl Iodides
	Elizabeth Susan Conner Balapitiya
		Recommended Citation
tmp.1483830367.pdf.mBCU8
                        
Document Text Contents
Page 1

Louisiana State University
LSU Digital Commons

LSU Doctoral Dissertations Graduate School

2015

I. Synthesis of Ascarosides for Biological Evaluation
and II. Development of Visible Light-Promoted
Selenofunctionalization and Grafting of Aryl
Iodides
Elizabeth Susan Conner Balapitiya
Louisiana State University and Agricultural and Mechanical College

Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations

Part of the Chemistry Commons

This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in
LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]

Recommended Citation
Balapitiya, Elizabeth Susan Conner, "I. Synthesis of Ascarosides for Biological Evaluation and II. Development of Visible Light-
Promoted Selenofunctionalization and Grafting of Aryl Iodides" (2015). LSU Doctoral Dissertations. 637.
https://digitalcommons.lsu.edu/gradschool_dissertations/637

https://digitalcommons.lsu.edu?utm_source=digitalcommons.lsu.edu%2Fgradschool_dissertations%2F637&utm_medium=PDF&utm_campaign=PDFCoverPages
https://digitalcommons.lsu.edu/gradschool_dissertations?utm_source=digitalcommons.lsu.edu%2Fgradschool_dissertations%2F637&utm_medium=PDF&utm_campaign=PDFCoverPages
https://digitalcommons.lsu.edu/gradschool?utm_source=digitalcommons.lsu.edu%2Fgradschool_dissertations%2F637&utm_medium=PDF&utm_campaign=PDFCoverPages
https://digitalcommons.lsu.edu/gradschool_dissertations?utm_source=digitalcommons.lsu.edu%2Fgradschool_dissertations%2F637&utm_medium=PDF&utm_campaign=PDFCoverPages
http://network.bepress.com/hgg/discipline/131?utm_source=digitalcommons.lsu.edu%2Fgradschool_dissertations%2F637&utm_medium=PDF&utm_campaign=PDFCoverPages
https://digitalcommons.lsu.edu/gradschool_dissertations/637?utm_source=digitalcommons.lsu.edu%2Fgradschool_dissertations%2F637&utm_medium=PDF&utm_campaign=PDFCoverPages
mailto:[email protected]

Page 108

92


conditions for the generation of aryl radicals from aryl iodides were then attempted (Scheme

4.3).

Before photografting under Lee’s conditions could be accomplished,

[Ir(ppy)2(dtbbpy)][PF6] was synthesized (Scheme 4.4). Phenylpyridine 86 was first reacted with

irdium (III) chloride hydrate in 2-ethoxyethanol to give the bimetallic species 87 in 67% yield.

The bimetallic intermediate 87 then underwent a ligand exchange with 4,4’-di-tert-butyl-2,2’-

bipyridyl in ethylene glycol with ammonium hexafluorophosphate to produce the desired

photocatalyst in 69% yield.

Ir

N

N

Ir

N

N

Cl

ClN 2-ethoxyethanol
67%

NH4PF6, ethylene glycol
69%

N

N

But
tBu

IrCl3
.
H2O

86

87

Ir

N

N

N

N

tBu

tBu

PF6

[Ir(ppy)2(dtbbpy)][PF6]

Scheme 4.4 Synthesis of [Ir(dtbbpy)(ppy)2][PF6]

For thin film synthesis under Lee’s conditions, 4-iodoanisole at an initial concentration of

0.01 M was placed in an Erlenmeyer flask with [Ir(dtbbpy)(ppy)2][PF6], DIPEA and MeCN in

the presence of TSG AFM gold plates
15

and irradiated for 18.5 hours. After removal of the silica

Page 109

93


mesospheres by sonication in ethanol, AFM images illustrated that a uniform thin film was

formed, but only at a thickness of ~1 nm (Figure 4.5).



Figure 4.5 AFM image of 4-anisyl on gold using Lee’s conditions with a 4-iodoanisole

concentration of 0.01 M

Because thicker films are often useful for further analysis by infrared reflection-

absorption spectroscopy (IRRAS) and XPS, the concentration of 4-iodoanisole was increased to

0.1M. Upon irradiation at this concentration and subsequent removal of the mesospheres, the

depth of the formed nanopores was determined to be 2 nm by AFM (Figure 4.6). To further

increase the anisole layer thickness, the 4-iodoanisole concentration was increased to 0.3 M and

irradiated for 18.5 hours. The resulting film, however, was demonstrated by AFM to be not

uniform in thickness across the entire surface, varying from 1-4 nm in depth. The most

consistent and homogenous result, therefore, was obtained by using the 4-iodoanisole

concentration of 0.1 M. To demonstrate that the thin film seen on AFM was not a result of

grafting of DIPEA or MeCN, a control experiment was run where only [Ir(dtbbpy)(ppy)2][PF6],

DIPEA and MeCN was irradiated with the Au(111) substrate. No film was present on AFM.

Page 215

199

Page 216

200

VITA

Elizabeth Susan Conner Balapitiya was born in Lafayette, Louisiana to Timothy C.

Conner and Mary B. Conner, and she is married to Nuwan N. Balapitiya. Following completion

of her primary studies in 2006, she enrolled at Baylor University in Waco, Texas where she

earned her Bachelors degree in May 2010 in the University Scholars program, focusing on

Chemistry and Spanish. The following August, she entered the doctoral program in the

Department of Chemistry at Louisiana State University in Baton Rouge, Louisiana. She later

joined the research group of Dr. Justin R. Ragains in December 2010. Elizabeth is currently a

candidate for a doctoral degree in Chemistry, which will be awarded at the May 2015

commencement ceremony.

Similer Documents