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«A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of ...»

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Figure A.9. Effect of I– on ∆δ of the NH signals of [Re(CO)3(dipn)]PF6 (1) in acetonitrile-d3 at 25 °C.

References

1. Karplus, M. J. Am. Chem. Soc. 1963, 85, 2870-2871.

2. Christoforou, A. M.; Fronczek, F. R.; Marzilli, P. A.; Marzilli, L. G. Inorg. Chem. 2007, 46, 6942-6949.

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Scheme B.1. Top: Proton transfer and Re–N4 to Re–N3 rearrangement processes that occur in the mechanism suggested for formation of the [Re(CO)3(DAE)]+ cation through an MAE-type intermediate. Bottom: When N3 in the seven-membered chelate ring has bonds only to carbon, the DAE-type ligand cannot form.

Figure B.1. Overlay of N–M–N atoms in the seven-membered chelate ring of [Re(CO)3(MAE)]PF6 (purple) and cis-[Pt(NH=CPhNButCH2CH2NHBut)Cl2] (gold), in which the metal projects toward the viewer (top) and away from the viewer (bottom).

Figure B.2. 1H-1H COSY NMR spectrum of [Re(CO)3(MAE)]PF6 in DMSO-d6 at 25 °C.

Figure B.3. ROESY spectrum of [Re(CO)3(DAE)]BF4 in DMSO-d6 at 25 °C showing negative EXSY cross-peaks (circled) between the –NH2 signals.

Figure B.4. 1H-1H COSY NMR spectrum of [Re(CO)3(DAE)]BF4 in DMSO-d6 at 25 °C.

Figure B.5. Dependence on temperature of NH 1H NMR signals of [Re(CO)3(DAE)]BF4 in acetonitrile-d3.

Figure B.6. ROESY spectrum of [Re(CO)3(DAE)]BF4 in acetonitrile-d3 at –5 °C showing negative EXSY cross-peaks (circled) between the –NH2 signals.

–  –  –

ORTEP plot of the cation in [Re(CO)3(5,5′-Me2bipy) Figure C.1.

(HNC(CH3)NHCH3)](BF4)0.52(ReO4)0.48 (6). Crystal data: monoclinic P21/c, a = 10.2235(15), b = 13.703(2), c = 15.391(2) Å, β = 98.671(10)° at T = 90 K, Z = 4, R = 0.065. Thermal ellipsoids are drawn with 50% probability. The data for this compound leave no doubt about the structure of the cation. However, because of the uncertainty surrounding the disordered anion, the structure is not included in the main text.

Figure C.2. Depictions of several amidine complex cations with the {Re(CO)3}+ core positioned in the same orientation. (a) [Re(CO)3(5,5′-Me2bipy)(Z-HNC(CH3)NH2)]BF4 (7); (b) [Re(CO)3(5,5′-Me2bipy)(E′-HNC(CH3)NHCH(CH3)2)]BF4, (2); and (c) [Re(CO)3(5,5′Me2bipy)(E′-HNC(CH3)NHC(CH3)3)]BF4 (4). Figure illustrates that the amidine ligand is oriented differently in these products.

Figure C.3. Depiction of stacking of the phenyl ring of the amidine moiety (gold) above one ring of the bipyridine ligand (green) in [Re(CO)3(5,5′-Me2bipy)(HNC(CH3)NHCH2C6H5)]BF4 (5) in the solid state.

Figure C.4. ROESY spectrum of [Re(CO)3(5,5′-Me2bipy)(HNC(CH3)NHCH(CH3)2)]BF4 (2) in acetonitrile-d3 at 25 °C, showing NOE peaks.

Figure C.5. NOE (top) and COSY (bottom) cross-peaks in ROESY and COSY spectra of [Re(CO)3(5,5′-Me2bipy)(HNC(CH3)NHCH(CH3)2)]BF4 (2) in acetonitrile-d3 at 25 °C.

Figure C.6. ROESY spectrum of [Re(CO)3(5,5′-Me2bipy)(HNC(CH3)NHCH(CH3)2)]BF4 (2) in CDCl3 at 25 °C, showing negative EXSY cross-peaks (circled) and NOE peaks.

Figure C.7. Starting with the structure of the E′ isomer of [Re(CO)3(5,5′Me2bipy)(HNC(CH3)NHCH(CH3)2)] (2), E, Z, and Z′ isomer models were constructed by using Chem3D Pro software. Rotations were performed to create short N3H-to-CH(isopropyl) nonbonded distances. Nonbonded distances were measured by using Mercury software, and all structures are illustrated as space-filling models by using this software. The closest N3H-toCH(isopropyl) distances found were 2.18, 4.18, 4.39 and 3.51 Å for the E′, E, Z, and Z′ isomers, respectively. Note that in the Z′ isomer the isopropyl group would clash with atoms in the equatorial plane defined by the 5,5′-Me2bipy ligand. It is evident that, while this distance is favorably long in both the E′ and E isomers, in the E isomer the isopropyl group would be rather close to the methyl group on the amidine carbon. This proximity can lead to clashes as the size of the R group increases.

Figure C.8. Scheme relating the identified isomers of [Re(CO)3(L)(HNC(CH3)NHR)]+ cations.

The figure illustrates the likely pathway between the Z and the E′ isomers, passing through the E isomer. Faster interconversion occurs between E and E′ isomers, as rotation about the bond between the amidine C and the remote N is expected to be faster compared to rotation about the bond between the amidine C and the N bound to Re.

Table C.1. Selected 1H NMR Shifts (ppm) for Re(CO)3[(5,5′-Me2bipy)(HNC(CH3)NHR)]BF4 in CDCl3 and in CD2Cl2 at 25 °C

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Figure D1. ORTEP plot of [Re(CO)3(5,5′-Me2bipy)(HNC(CH3)OCH2CH3)]BF4.

Thermal ellipsoids are drawn with 50% probability.

Table 1. Crystal Data and Structure Refinement for [Re(CO)3(CH3CN)3]BF4 (1b) and [Re(CO)3(5,5′-Me2bipy)(HNC(CH3)OCH2CH3)]BF4 [Re(CO)3 (CH3CN)3]BF4 [Re(CO)3(5,5′-Me2bipy)(HNC(CH3)OCH2CH3)]BF4

–  –  –

R = (∑||Fο| - |Fc||)/∑|Fο|. bwR2 = [∑[w(Fο2 - Fc2)2]/∑[w(Fο2)2]]1/2, in which w = 1/[σ2(Fο2) + a (dP)2 + (eP)] and P = (Fο2 + 2Fc2)/3, and d = 0.0214, and 0.0286 and e = 1.5711, and 3.2659 for [Re(CO)3(CH3CN)3]BF4, and [Re(CO)3(5,5′-Me2bipy)(HNC(CH3)OCH2CH3)]BF4.

–  –  –

Figure E.1. 1H NMR spectra of N(SO2Me)dpa (bottom), N(SO2tmb)dpa (middle), and N(dansyl)dpa (top) in DMSO-d6 at 25 °C.

Figure E.2. ORTEP plots of Pt(N(SO2Me)dpa)Cl2 (left), and Pt(N(SO2tmb)dpa)Cl2 (right).

Thermal ellipsoids are drawn with 50% probability.

APPENDIX F

PERMISSION

–  –  –

Theshini Perera was born in Colombo, Sri Lanka, to Mahima and Newton Perera as the youngest and only daughter, and was brought up as the apple of everyone’s eye! She had her primary and secondary education at Ladies’ College, Colombo, where she was Head Girl and was awarded the most outstanding girl of the year award in 1996. She entered the University of Colombo in year 2000 and graduated with an Honors Degree in chemistry in 2004.

After serving for a few months as a teaching assistant at the Department of Chemistry, University of Colombo, she moved on to the academic staff at the University of Sri Jayewardenepura, where she was hired as a lecturer in chemistry.

She arrived in the United States in August 2006 with her husband Inoka, after celebrating only their first anniversary in her home country. She joined the laboratory of Prof. Luigi Marzilli in January 2007 where she carried out her doctoral research work on Re tricarbonyl complexes of biomedical relevance. She is a candidate for the degree of Doctor of Philosophy in the Summer Commencement 2010. She is looking forward to returning to her motherland where she will continue to educate young undergraduates.



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