Photoinduced and Thermal Linkage Isomerizations of an Organometallic Ionic Liquid Containing a Half-Sandwich Ruthenium Thiocyanate Complex

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Table of Contents

An ionic liquid containing a cationic half-sandwich Ru thiocyanate complex was synthesized.

Isomerization from the N- to the S-coordinated isomer occurred upon UV photoirradiation or

heating.

21

Supporting Information

Photoinduced

and

Thermal

Linkage

Isomerizations

of

an

Organometallic Ionic Liquid Containing a Half-Sandwich Ruthenium

Thiocyanate Complex

Tomoyuki Mochida,*a,b Syou Maekawa,a and Ryo Sumitania

Department of Chemistry, Graduate School of Science, Kobe University, Rokkodai, Nada, Kobe,

Hyogo 657-8501, Japan. E-mail: tmochida@platinum.kobe-u.ac.jp

Research Center for Membrane and Film Technology, Kobe University, Rokkodai, Nada, Kobe,

Hyogo 657-8501, Japan

Contents

Figure S1. 1H NMR spectra of the compounds synthesized in this study.

Figure S2. IR spectra of the N-coordinated and S-coordinated isomers and [1]Tf2N.

Figure S3. DSC thermograms of [1]Tf2N and [1]PF6.

Figure S4. TG-DTA thermograms of [1]Tf2N and [1]PF6.

Figure S5. IR spectra of the N-coordinated isomer taken upon photoirradiation.

Figure S6. Optimized geometries of the N- and S-coordinated isomers obtained using DFT

calculations.

Figure S7. 1H NMR spectra of [1]Tf2N (N:S = 0.73:0.27, CDCl3 solution) measured before and

after heating.

Figure S8. UV-Vis spectra and photographs of the N-coordinated and S-coordinated isomers in

dichloromethane and methanol.

S1

[RuCl(C6H6)L]PF6

[1]PF6 (N:S = 0.73:0.27)

[1]Tf2N (N:S = 0.73:0.27)

S2

[1']Tf2N (after thermal isomerization, N:S = 0.35:0.65)

Figure S1. 1H NMR spectra of the compounds synthesized in this study (CDCl3).

Figure S2. IR spectra of (a) the N-coordinated and S-coordinated isomers and (b) [1]Tf2N and

[1']Tf2N (after thermal isomerization).

S3

Figure S3. DSC thermograms of [1]Tf2N (left) and [1]PF6 (right).

Figure S4. TG (—) and DTA (---) thermograms of (a) [1]Tf2N (10 and 3 °C min−1) and (b) [1]PF6

(10 °C min−1).

2102 cm–1

2110 cm–1

Figure S5. IR spectra of the N-coordinated isomer taken upon photoirradiation (KBr plate,

transmission spectra).

S4

N-coordinated isomer

S-coordinated isomer

Eel+ZPE, G0 (au)

−1197.5804, −1197.6220

−1197.5820, −1197.6236

HOMO, LUMO (eV)

−10.48, −4.14

−11.10, −4.20

Figure S6. Optimized geometries of the N- and S-coordinated isomers obtained using DFT

calculations. The total energy (Eelectronic+ZPE), Gibbs energy (G0), and energies of the

HOMO/LUMO levels of each isomer are shown below each structure.

Figure S7. 1H NMR spectra of [1]Tf2N (N:S = 0.73:0.27, CDCl3 solution) (a) Before heating, (b)

after 1 day and (c) after 6 days of heating at 50 °C.

S5

Figure S8. UV-Vis spectra and photographs of the N-coordinated (—) and S-coordinated (---)

isomers in (a) dichloromethane and (b) methanol (concentrations: 80 mol L−1).

S6

...