Appendix A: Supplementary Materials
Synthesis and pH-dependent spectroscopic behavior of 2,4,6trisubstituted pyridine derivatives
Gala Chapman, Isaac Solomona, Gabor Patonay*b, and Maged Henary*c
Department of Chemistry, Georgia State University, P.O. Box 4098, Atlanta, Georgia 30302-4098, USA.
a
Undergraduate student (senior research in Dr. Henary’s lab)
*b Corresponding author. Tel: +1 404 413 5556; E-mail address: gpatonay@gsu.edu
*c Corresponding author. Tel: +1 404 413 5566; E-mail address: mhenary1@gsu.edu
Appendix A: Supplementary Materials
Figure A.1. 1H NMR spectrum of compound 1 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.2. 1H NMR spectrum of compound 2 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.3. 1H NMR spectrum of compound 3 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.4. 1H NMR spectrum of compound 4 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.5. 1H NMR spectrum of compound 5 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.6. 1H NMR spectrum of compound 6 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.7. 1H NMR spectrum of compound 7 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.8. 13C NMR spectrum of compound 1 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.9. 13C NMR spectrum of compound 2 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.10. 13C NMR spectrum of compound 3 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.11. 13C NMR spectrum of compound 4 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.12. 13C NMR spectrum of compound 5 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.13. 13C NMR spectrum of compound 6 in DMSO-d6
Appendix A: Supplementary Materials
Figure A.14. 13C NMR spectrum of compound 7 in DMSO-d6
Appendix A: Supplementary Materials
Molar Absorptivity of Nonprotonated and Singly Protonated Forms of Compounds:
Methodology and Representative Spectra
Method of Determination of Molar Absorptivity of Base form of Compounds:
1. Samples containing varying [compound] prepared in ACN and absorption spectra acquired
0.9
0.8
 MAX = 343 nm
0.7
0.6
0.5
A
0.4
0.3
0.2
0.1
0
290
340
390
440
490
 (nm)
Figure A.15. Absorption spectra from determination of molar absorptivity of base form of
compound 7 (2.5 - 20 M in ACN)
2. Absorption at MAX plotted as a function of concentration, slope of least squares line taken as
molar absorptivity
0.8
0.7
y = 35331x - 0.0007
R² = 0.9999
0.6
A343 nm
0.5
0.4
0.3
0.2
0.1
0
0.00E+00 5.00E-06 1.00E-05 1.50E-05 2.00E-05 2.50E-05
Conc. (M)
Figure A.16. Plot of absorption as a function of concentration for compound 7 (base form)
Appendix A: Supplementary Materials
Method of Determination of Molar Absorptivity of Singly Protonated form of Compounds:
1. Preliminary protonation study carried out
with strong acid of choice in which [acid]
varied while [compound] is held constant
(≈ 20 M)
 MAX = 448 nm
0.8
50 M HCl
0.7
0.6
0.5
Approximate [acid] corresponding to
all compound being in its singly
protonated form determined to be the
[acid] resulting in highest absorptivity
of red-shifted protonation peak
A

0.9
0.4
0.3
0.2
0.1
0
300
350
400
450
 (nm)
500
550
Figure A.17. Protonation study of 20 M
compound 7 with HCl in ACN (excerpt)
0.9
 MAX = 448 nm
0.8
2. [Acid] held constant while [compound]
varied in molar absorptivity determination
0.7
0.6
0.5
A
0.4
0.3
0.2
0.1
0
300
350
400
450
500
550
 (nm)
Figure A.18. Absorption spectra of 2.5 - 20
M compound 7 protonated with 50 M HCl
in ACN
0.8
0.7
y = 38278x - 0.0243
R² = 0.9996
0.6
0.5
A448 nm
3. Absorption at red-shifted protonation peak
MAX plotted as a function of
concentration and slope of least squares
line taken as molar absorptivity
0.4
0.3
0.2
0.1
0
0.00E+00 5.00E-06 1.00E-05 1.50E-05 2.00E-05 2.50E-05
Conc. (M)
Figure A.19. Absorption as a function of
concentration for protonated compound 7