Syntheses and properties of phosphine-substituted ruthenium(II) polypyridine complexes with nitrogen oxides

View Article Online

View Journal

Dalton

Transactions

Accepted Manuscript

This article can be cited before page numbers have been issued, to do this please use: G. Nakamura, M.

Kondo, M. Crisalli, S. K. Lee, A. Shibata, P. C. Ford and S. Masaoka, Dalton Trans., 2015, DOI:

10.1039/C5DT02994E.

This is an Accepted Manuscript, which has been through the

Royal Society of Chemistry peer review process and has been

accepted for publication.

Accepted Manuscripts are published online shortly after

acceptance, before technical editing, formatting and proof reading.

Using this free service, authors can make their results available

to the community, in citable form, before we publish the edited

article. We will replace this Accepted Manuscript with the edited

and formatted Advance Article as soon as it is available.

You can find more information about Accepted Manuscripts in the

Information for Authors .

Please note that technical editing may introduce minor changes

to the text and/or graphics, which may alter content. The journal’s

standard T erms & Conditions and the Ethical guidelines still

apply. In no event shall the Royal Society of Chemistry be held

responsible for any errors or omissions in this Accepted Manuscript

or any consequences arising from the use of any information it

contains.

www.rsc.org/dalton

Page 1 of 13

Dalton Transactions

Journal Name

RSCPublishing

View Article Online

DOI: 10.1039/C5DT02994E

ARTICLE

Syntheses and Properties of Phosphine-Substituted

Ruthenium(II) Polypyridine Complexes with Nitrogen

Oxides

Cite this: DOI: 10.1039/x0xx00000x

Go Nakamura,^abMio Kondo,^abcdMeredith Crisalli,^eSze Koon Lee,^aAkane

Shibata,^aPeter C. Ford,^eand Shigeyuki Masaoka*^abd

Received 00th January 2012,

Accepted 00th January 2012

DOI: 10.1039/x0xx00000x

Four novel phosphineꢀsubstituted ruthenium(II) polypyridine complexes with nitrogen

www.rsc.org/

oxides—trans(P,NO₂)ꢀ[Ru(trpy)(Pqn)(NO₂)]PF₆

[Ru(trpy)(Pqn)(NO₂)]PF₆cis-NO₂), Ru(trpy)(dppbz)(NO₂)]PF₆

[Ru(trpy)(Pqn)(NO)](PF₆)₃cis-NO)—were synthesised (trpy = 2,2’:6’,2”ꢀterpyridine, Pqn =

(

trans-NO₂),

cis(P,NO₂)ꢀ

(

[

(

PP-NO₂), and cis(P,NO)ꢀ

(

8ꢀ(diphenylphosphanyl)quinoline, and dppbz = 1,2ꢀbis(diphenylphosphanyl)benzene). The

influence of the number and position of the phosphine group(s) on the electronic structure of

these complexes was investigated using singleꢀcrystal Xꢀray structural analysis, UVꢀvis

absorption spectroscopy, and electrochemical measurements. The substitution lability of the

nitrogen oxide ligand of each complex is discussed in comparison with that of the

corresponding acetonitrile complexes.

their catalytic activity for various reactions, such as

oxidation,^6,7reduction,^8ꢀ11and photoꢀinduced reactions.¹²

Introduction

Ruthenium(II) polypyridine complexes are widely studied

materials because of their contributions to fundamental

coordination

photochemistry, and photophysics,¹and their potential

applications in energy conversion,²luminescent sensors,³

electroluminescence displays,⁴and biotechnology.⁵Of

particular interest are the Ru(II) complexes [Ru(TL)(BL)(L)]ⁿ⁺

Phosphineꢀcontaining ruthenium(II) complexes are also

attractive for potential applications in energy conversion

systems¹³and catalysis^14ꢀ17owing to the σꢀdonating and πꢀ

accepting abilities of the phosphine ligands. Thus, it should be

possible to develop ruthenium complexes that have novel and

tunable properties and reactivity by designing mixed

polypyridyl/phosphine complexes. There have been several

reports on the syntheses of ruthenium(II) polypyridine

complexes containing monodentate phosphine ligands^18,19and

chemistry,

including

electrochemistry,

(TL

= tridentate polypyridine ligand, BL = bidentate

polypyridine ligand, and L = monodentate labile ligand) given

their catalytic activities^19d,20

.

However, ruthenium(II)

polypyridine complexes of the type [Ru(TL)(BL)(L)]ⁿ⁺bearing

bidentate ligands with P and N donors have not been

investigated.

In our previous report,²¹we synthesised and structurally

characterised for the first time a series of phosphineꢀcontaining

ruthenium(II) polypyridine complexes of the type

[Ru(TL)(BL)(L)]ⁿ⁺, with L = acetonitrile, TL = 2,2’:6’,2”ꢀ

terpyridine (trpy), and BL = 8ꢀ(diphenylphosphanyl)quinoline

(Pqn) or 1,2ꢀbis(diphenylphosphanyl)benzene (dppbz) (Scheme

1). The influence of the number and position of phosphine

donors on the structures and electronic properties was

characterised, and unique isomerisation behaviours of these

complexes were observed. The coordinating phosphorous

ligands played a crucial role in these isomerisation reactions,

and the results encouraged us to investigate in more detail the

Scheme 1 Structures of a tridentate ligand (trpy), bidentate ligands (Pqn and

dppbz), and metal complexes (trans-NO₂, cis-NO₂, PP-NO₂, and cis-NO) used in

this study.

This journal is © The Royal Society of Chemistry 2013

J. Name., 2013, 00, 1-3 | 1

Dalton Transactions

Page 2 of 13

Journal Name

ARTICLE

influence of the P atom on the physical properties of Ruꢀbased ³¹P{¹H} NMR spectroscopy and elemental analysis.

metal complexes.

The ³¹P{¹H} NMR spectra of trans-NO₂and cis -NO₂in

In this study, we investigated the reaction of phosphineꢀ CD₃CN displayed singlets at

53.10 and 54.06,^Vr^iee^wsp^Are^tic^clt^eiv^Oe^nllⁱⁿy^e,

containing ruthenium complexes with the nitrogen oxides, NO showing upfield shifts (ꢁδ = 5.70 and 1.90) compared to the

δ

DOI: 10.1039/C5DT02994E

−

and NO₂, because of their biological roles as signalling spectra of the corresponding acetonitrile complexes, trans

molecules²²and reservoirs,²³in addition to the fundamental MeCN and cis-MeCN 58.80 and 55.96). The ³¹P{¹H} NMR

interest in their coordination chemistry. Here, we show the spectrum of PP-NO₂in CD₃CN afforded two doublets at

syntheses, structural characterisation, and electrochemical and 62.65 and 68.59 with coupling constants of 14.2 Hz, again

spectroscopic properties of series of ruthenium(II) showing upfield shifts (ꢁδ = 5.85 and 1.18, respectively)

polypyridine complexes containing Pqn or dppbz with nitric compared with the spectrum of PP-MeCN (68.57 and 69.77,

oxides. Three novel nitritoꢀκ

complexes—trans(P,NO₂)ꢀ and ²J_P−P= 20.2 Hz).

cis(P,NO₂)ꢀ[Ru(trpy)(Pqn)(NO₂)]PF₆(trans-NO₂and cis-NO₂), Conversions of the nitritoꢀκ

and Ru(trpy)(dppbz)(NO₂)]PF₆(PP-NO₂)—were successfully corresponding ruthenium nitrosyls were attempted by adding an

synthesised. Described here are the singleꢀcrystal Xꢀray excess of HPF₆to acetone solutions of the nitritoꢀκ species at

structural determinations, UVꢀvis absorption spectra, and 0°C. The preparations of trans-NO and PP-NO from trans

electrochemical measurements for these complexes, and the NO₂and PP-NO₂, respectively, were not successful because of

preparation of the nitrosyl complex cis(P,NO) the instability of the nitrosyl complex or of a reaction

[Ru(trpy)(Pqn)(NO)](PF₆)₃cis-NO) from cis-NO₂and its intermediate under acidic conditions (for details, see Figures

-

(

δ

a

N

complexes to the

[

N

-

ꢀ

(

properties are examined. The present study allows us to probe S1ꢀ2 in the ESI). However, cis-NO was isolated in 85% yield

1

systematically the chemical and structural properties of and was characterised by H and ³¹P{¹H} NMR spectroscopy

phosphineꢀcontaining ruthenium complexes with nitrogen and elemental analysis. The ³¹P{¹H} NMR spectrum of cis-NO

oxides by the use of the geometric isomers of the Pqn complex. in acetoneꢀd₆gave a singlet at

δ 54.23. cis-NO immediately

Additionally, other reactivity properties and comparisons with converted to a solventꢀcoordinated complex in acetonitrile

those of the corresponding acetonitrile complexes are presented. (Figure S3 in the ESI) but was metaꢀstable in weakerꢀ

coordinating solvents, such as acetone, γꢀbutyrolactone and

ethylene glycol (Figure S4 in the ESI). The difference in the

stability of these nitrosyl complexes will be discussed in the

“Substitution Lability of Nitrogen Oxide” section.

Results and discussion

Syntheses and Characterisation

The synthetic procedures to obtain trans-NO₂, cis-NO₂, and

Crystal Structures

PP-NO₂are shown in Scheme 2. The precursors, trans-MeCN

,

Single crystals of trans-NO₂and PP-NO₂suitable for structural

Table 1 Crystallographic data for trans-NO₂, cis-NO₂’, and PP-NO₂.

cis-MeCN, and PP-MeCN, were synthesised according to the

method that we previously reported.²¹The reaction of the

respective acetonitrile complexes with excess NaNO₂in a 1:1

mixture of ethanol:water at 100°C gave the corresponding

nitritoꢀκ

The resulting products were characterised by ¹H NMR and

Complex

trans-NO₂·CH₃CN

cis-NO₂'·0.5CH₃CN

PP-NO₂·2CH₃OH

N complexes (trans-NO₂,

cis-NO₂, and PP-NO₂).^24,26b

Formula

C₃₈H₃₀F₆N₆O₂P₂Ru

879.69

C₆₁H_48.5BN_5.5O₂PRu

1033.40

C₄₇H₄₃F₆N₄O₄P₃Ru

1035.83

orange, block

monoclinic

0.15 × 0.10 × 0.05

P2₁/c

Formula weight

Crystal colour, habit

Crystal system

Crystal size, mm³

Space group

a, Å

red, needle

monoclinic

0.30 × 0.05 × 0.05

P2₁/n

orangeꢀred, platelet

triclinic

0.15 × 0.15 × 0.10

ꢀ

P1

12.1909(17)

11.9003(17)

25.260(4)

90

10.2764(2)

21.2343(4)

24.3802(4)

77.0060(10)

78.9530(10)

74.9360(10)

4955.30(16)

4

17.1049(6)

13.0763(6)

20.1547(8)

90

b, Å

c, Å

α

, º

β

99.579(3)

90

106.853(3)

90

γ

V, Å³

3613.5(9)

4

4314.4(3)

4

Z

D_calc, g cm^ꢀ3

1.617

1.385

1.595

ꢀ

, mm^ꢀ1

0.599

0.400

0.552

F(000)

1776

2132

2112

a

R₁

0.0596

0.0337

0.0397

b

wR₂

0.1678

0.1071

0.0941

Goodnessꢀofꢀfit S

1.032

1.178

1.004

Scheme 2 Syntheses of trans-NO₂, cis-NO₂, PP-NO₂, and cis-NO. (i) NaNO₂in 1:1

mixture of ethanol:water at 100ºC. (ii) HPF₆in acetone at 0ºC.

[a] R₁= –Σ||Fo|–|Fc|| / Σ|Fo|. [b] wR₂= [Σ(w(Fo²–Fc²)²) / Σw(Fo²)²]^1/2

2 | J. Name., 2012, 00, 1-3

This journal is © The Royal Society of Chemistry 2012

Page 3 of 13

Journal Name

Dalton Transactions

ARTICLE

View Article Online

DOI: 10.1039/C5DT02994E

Figure 2 Comparison of bond distances (Å) around the ruthenium centres of

trans-NO₂cis-NO₂’, and PP-NO₂

,

.

–

ruthenium complexes, two BPh₄anions, and one acetonitrile

molecule as the crystal solvent in the asymmetric unit of the

triclinic

P1¯ space group. The asymmetric unit of the monoclinic

P

2₁/c crystal of PP-NO₂contained one cationic ruthenium

complex, one PF₆anion, and two methanol molecules. For each

complex, the ratio of ruthenium to counter anion indicated that

the oxidation state of the ruthenium centre was +2. The

coordination geometry of each Ru atom was that of a distorted

octahedron composed of a meridionally coordinated terpyridine

ligand, a bidentate ligand, and a nitrito ligand.

The bond distances between the ruthenium and nitrogen

atoms of the nitrito ligand of trans-NO₂and PP-NO₂were

2.146(4) (Ru1–N5) and 2.124(2) Å (Ru1–N4), respectively

(Figure 2), and were longer than those found in

[Ru(trpy)(bpm)(NO₂)]PF₆(2.034(5) Å, bpm

=

2, 2’ꢀ

bipyrimidine).²⁵By contrast, the Ru–N(NO₂) distances in cis

-

NO₂’ (2.0362(18) and 2.0290(18) Å for Ru1–N5 and Ru2–N10,

respectively, Figure 2) were similar to those of

[Ru(trpy)(bpm)(NO₂)]PF₆(2.034(5) Å). These results indicated

a stronger trans influence of the phosphorous atom of Pqn or

dppbz compared with that of the nitrogen atom of bpm or bpy.

This tendency was also observed in trans-MeCN

and PP-MeCN in our previous study.²¹

, cis-MeCN,

UV-Vis Absorption Spectra

Figure 3 shows the UVꢀVis absorption spectra of the nitritoꢀκ

N

Figure 1 ORTEP drawings (50% probability level) of cationic complexes in (a)

trans-NO₂, (b) cis-NO₂’, and (c) PP-NO₂. Hydrogen atoms are omitted for clarity.

determination were obtained by recrystallisation from diethyl

ether/methanol/acetonitrile. Single crystals of the cisꢀnitritoꢀκ

complex were obtained as the BPh₄salt, cis(P,NO₂)

N

ꢀ

–

[Ru(trpy)(Pqn)(NO₂)]BPh₄(cis-NO₂’), by adding an excess of

NaBPh₄, instead of NH₄PF₆, after the reaction. The molecular

structures of trans-NO₂, cis-NO₂’, and PP-NO₂determined by

singleꢀcrystal Xꢀray crystallography and the summary of

crystallographic data are shown in Figure 1 and Table 1,

respectively. The asymmetric unit of the monoclinic

P2₁/n

crystal of trans-NO₂contained one cationic ruthenium complex,

one PF₆anion, and one acetonitrile molecule. The cis-NO₂’

crystallised with two crystallographically independent

Figure

3 UV-Vis absorption spectra of trans-NO₂, cis-NO₂, and PP-NO₂in

acetonitrile at room temperature.

This journal is © The Royal Society of Chemistry 2012

J. Name., 2012, 00, 1-3 | 3

Dalton Transactions

Page 4 of 13

Journal Name

ARTICLE

View Article Online

DOI: 10.1039/C5DT02994E

Figure 4 UV-Vis absorption spectra of cis(P,X)-[Ru(trpy)(Pqn)(L)]ⁿ(L = Cl⁻, NO₂,

MeCN, NO⁺) in ethylene glycol at room temperature.

Figure 5 Cyclic voltammograms of trans-NO₂

,

cis-NO₂, and PP-NO₂(0.5 mM) in

0.1 M TEAP/acetonitrile under Ar atmosphere (WE: GC, CE: Pt wire, RE: Ag/Ag⁺;

Scan rate: 100 mV/s).

complexes, trans-NO₂, cis-NO₂, and PP-NO₂, in acetonitrile

The UVꢀvis absorption spectra of the cisꢀisomers with

different ligands L, cis(P,L)ꢀ[Ru(trpy)(Pqn)(L)]ⁿ⁺(L = Cl^–,

solution. The spectral data for these complexes and related

compounds are listed in Table 2. All complexes displayed

intense absorption bands in the UV region that were assigned to

ligandꢀbased π–π* transitions. Additionally, a moderately

intense band was observed in the visible region for each

complex. TDꢀDFT calculations that were performed at the

B3LYP/LANL2DZ and B3LYP/SDD level of theory indicated

that the visible region band could be assigned to metalꢀtoꢀ

ligand charge transfer (MLCT) transitions from the dπ orbitals

of ruthenium to the π* orbitals of trpy and Pqn or dppbz (for

details, see Table S1 and Figures S5ꢀ9 in the ESI). The molar

absorption coefficient of PP-NO₂was nearly half those of

–

NO₂, MeCN, and NO⁺), in ethylene glycol solution are shown

in Figure 4. These complexes each exhibited ligandꢀbased π–π*

transitions in the UV region and MLCT transitions in the

visible region. The MLCT transition of cis-NO was observed at

λ_max= 383 nm and is comparable to similar RuꢀNO complexes

(Table 3). For the different Ls, the lowest energy MLCT bands

of the cisꢀisomers are in the following order: L = Cl^–(468 nm)

–

< NO₂(423 nm) < MeCN (413 nm) < NO⁺(383 nm). This

result can be attributed to the competing

properties of the respective ligands.

σꢀdonor/πꢀacceptor

trans-NO₂and cis-NO₂. The absorption maximum (

λ_max) of the

Electrochemical Properties

MLCT transition of trans-NO₂cis-NO₂, and PP-NO₂was 443,

,

431, and 402 nm, respectively, and was blueꢀshifted compared The cyclic voltammograms (CVs) of trans-NO₂

,

cis-NO₂, and

25

with that of [Ru(trpy)(bpm)(NO₂)]PF₆

suggesting the PP-NO₂are shown in Figure 5, and electrochemical data for

,

stabilisation of the dπ orbitals of the ruthenium centre upon these complexes and related compounds are listed in Table 4.

introduction of the phosphine donors. Note that the MLCT band The CVs were measured in 0.1 M tetraethylammonium

of cis-NO₂was more blueꢀshifted than that of trans-NO₂perchlorate (TEAP)/acetonitrile. cis-NO₂displayed one

despite their isomeric relationship. A similar pattern was noted reversible oxidation wave in the positive region at

for the acetonitrile complexes, trans-MeCN

cis-MeCN, and vs. ferrocene/ferrocenium (Fc/Fc⁺), which was assigned to a

PP-MeCN ²¹

Ru(III)/Ru(II) redox couple. By contrast, trans-NO₂and PP-

E_1/2= 0.79 V

,

.

Table 2 UVꢀVis absorption data (λ_max/nm (10^–3ε/M^–1cm^–1)) in acetonitrile and infrared data (v/cm^–1) for trans-NO₂, cis-NO₂, PP-NO₂, and related compounds

at room temperature.

IR

complex

λ_max

v_as(NO₂)

v_s(NO₂)

trans-NO₂

cis-NO₂

443 (8.02), 327^c, 303 (31.0), 281 (23.9), 271 (24.1)

1349

1304

431 (7.95), 331^c, 315 (29.7), 282 (26.9), 276^c

402 (3.82), 332 (12.6), 307 (17.7), 283 (16.5), 273 (17.5)

472

1339

1286

PP-NO₂

1354

1311

[Ru(trpy)(bpy)(NO₂)]PF₆^a

[Ru(trpy)(bpm)(NO₂)]PF₆^b

d

470 (6.50), 362 (6.10), 330^c, 308 (25.6), 264 (23.3)

1342

1286

[a] Reference 26. [b] Reference 25. [c] Absorption shoulder. [d] Data not collected.

4 | J. Name., 2012, 00, 1-3

This journal is © The Royal Society of Chemistry 2012

Page 5 of 13

Journal Name

Dalton Transactions

ARTICLE

View Article Online

DOI: 10.1039/C5DT02994E

Figure 6 Cyclic voltammogram of cis-NO (0.5 mM) in 0.1 M TEAP/γ-butyrolactone

under an Ar atmosphere (WE: GC, CE: Pt wire, RE: Ag/Ag⁺; Scan rate: 100 mV/s).

Figure 7 Cyclic voltammograms of cis-Cl

,

cis-NO₂, and cis-MeCN (0.5 mM) in 0.1

M TEAP/acetonitrile under an Ar atmosphere (WE: GC, CE: Pt wire, RE: Ag/Ag⁺;

Scan rate: 100 mV/s).

NO₂exhibited one irreversible (E_pa= 0.79 for trans-NO₂and

0.95 V for PP-NO₂) and one reversible (E_1/2= 0.97 for trans

-

−1.47 V) and one reversible (

negative region. The reversible wave at E_1/2= −2.49 V and the

irreversible anodic wave at _pa= −1.47 V were similar to those

E_1/2= −2.49 V) redox wave in the

NO₂and 1.27 V for PP-NO₂) redox waves in the positive

region The former irreversible oxidation peak can be attributed

to oxidation of the (RuꢀNO₂)⁺centre, and the latter reversible

wave was observed exactly at the same potential as the

Ru(III)/Ru(II) redox couple of the corresponding acetonitrile

complex (E_1/2= 0.97 for trans-MeCN and 1.27 V for PP-

MeCN, Table 4 and Figures S10b and 10d in the ESI).²¹These

E

observed for PP-MeCN (Table 4 and Figure S10c in the ESI).

These redox behaviours of trans-NO₂and PP-NO₂revealed

that the reduction of these complexes induced the dissociation

–

of NO₂and the formation of MeCNꢀcoordinated species; this

behaviour was similar to that observed in the positive potential

observations suggest that the oneꢀelectron oxidation of trans

-

region. The electrochemical behaviours of the nitritoꢀκ

complexes are summarised in Scheme 3.

N

NO₂and PP-NO₂results in the release of NO₂, owing to the

labilising effect of the transꢀphosphine in each case. This leads

to the formation of the respective ruthenium(II) acetonitrile

complexes, which are oxidised reversibly on further sweep to

cis-NO displayed one reversible redox wave at E_1/2= 0.05

V and one irreversible reduction peak at E_pc= −0.61 V (Figure

6). Comparison with similar nitrosyl compounds^24,25revealed

that the former redox wave was attributed to NO⁺/NO^•redox

couple and the latter peak could be assigned to the reduction of

NO^•to NO⁻. Note that a Ru(III)/Ru(II) redox couple was not

observed in the potential region between −1.6 to 1.5 V due to

the low HOMO energy level originating from the poor donating

ability of the NO⁺ligand.

more positive potential (Scheme 3). In the absence of a trans

ꢀ

labilising phosphine, the oxidation of the (RuꢀNO₂)⁺centre of

cis-NO₂occurs at a similar potential to the transꢀisomer, but

reversibly (Figure 5 and Table 4).

In the negative potential region, cis-NO₂displayed two

reversible reduction waves at −1.70 and −1.99 V, which were

assigned to the trpy/trpy^–and Pqn/Pqn^–redox couple,

Cyclic voltammograms of cisꢀisomers with various ligands

L are shown in Figure 7. The redox potentials of a

Ru(III)/Ru(II) redox couple for each complex were observed at

respectively. trans-NO₂exhibited two redox waves at E_1/2

−1.77 and −2.13 V, and these redox potentials were the same as

that of trans-MeCN (Table 4 and Figure 10a in the ESI PP-

NO₂displayed two irreversible waves ( _pc= −1.70 V and E_pa

=

0.49, 0.79, and 1.05 V for cis(P,Cl)ꢀ[Ru(trpy)(Pqn)(Cl)]⁺(cis

-

)

.

E

=

Table 3 UVꢀVis absorption data (λ_max/nm (10^–3ε/M^–1cm^–1)) in acetonitrile, infrared data (v/cm^–1), and redox potentials (E_1/2/V vs Fc/Fc⁺) in acetonitrile for cis-

NO and related compounds at room temperature.

complex

λ_max

v_N−O

1929

1957

1900

E_1/2(NO⁺/NO^•)

0.05

E_1/2(NO^•/NO⁻)

cis-NO^a

[Ru(trpy)(bpm)(NO)](PF₆)₃

trans(P,P)ꢀ[Ru(trpy)(PPh₃)₂(NO)](ClO₄)₃

383 (8.38), 329 (17.9), 323^d, 287 (23.7), 279^d

362 (5.12), 331^d, 312^d, 291 (8.93), 265 (10.8)

393^d, 330 (32)

–0.61^e

b

0.17

–0.47

c

f

0.12

[a] UVꢀVis absorption data and redox potentials in ethylene glycol and γꢀbutyrolactone, respectively. [b] Reference 25. [c] Reference 24 [d] Absorption

shoulder. [e] E_pcvalue for the irreversible process. [f] Data not collected.

This journal is © The Royal Society of Chemistry 2012

J. Name., 2012, 00, 1-3 | 5

Dalton Transactions

Page 6 of 13

Journal Name

ARTICLE

View Article Online

DOI: 10.1039/C5DT02994E

Figure 8 UV-Vis absorption spectra of cis-NO in ethylene glycol at room

temperature during photolysis using a Nd/YAG laser operating at 355 nm. “Times”

indicates the number of the laser pulses used to irradiate the sample.

S13 in the ESI), which suggests that the photodissociation of

NO and the isomerization of the complex from cis to trans form

proceeds in a stepꢀwise manner. The result is consistent with

the multiꢀstep spectral change shown in Figure 8. It should

further be noted that a Ru(II) complex, rather than the Ru(III)

species is obtained upon NO photodissociation from cis-NO

(ESI Figure S13). There are several possible explanations, one

being that the Ru(III) intermediate is readily reduced by the

solvent. Another is that the principal photoꢀreaction is release

of NO⁺rather than NO²⁷owing to phosphine stabilization of the

lowꢀvalent Ru(II) state. However, this question was not

explored in greater detail.

Scheme 3 Electrochemical behaviour of nitrito-κN complexes.

Cl), cis-NO₂, and cis-MeCN, respectively. This result indicated

the increase in the HOMO energy level by electron donation

from monodentate ligands and was consistent with the UVꢀvis

absorption spectroscopy.

Photostability of a Nitrosyl Complex

The photostability of cis-NO was investigated by UVꢀvis

absorption spectroscopy and by using a Sievers nitric oxide

analyser (NOA) to evaluate NO release. When a solution of cis

-

NO in ethylene glycol (0.05 mM) was irradiated at λ_irr= 355

nm, the slow spectral changes seen in Figure 8 were observed.

Substitution Lability of Nitrogen Oxide

The substitution lability of the monodentate ligand L in the

[Ru(TL)(BL)(L)]ⁿ⁺ꢀtype complexes is an important factor in

determining the reactivity of the complexes in various catalytic

and photoꢀinduced reactions. Several experimental results

described above enabled us to discuss in detail the lability of

the monodentate ligand in the complexes. First, the reaction of

cis-NO₂with HPF₆afforded the desired cis-NO. However, the

similar reactions of trans-NO₂and PP-NO₂resulted in the

The quantum yields of NO release,

Φ_NO, were quite low, 0.0048

in air saturated solution and 0.003 under helium (ESI Figures

S11ꢀ12). These Φ_NOvalues are about two orders of magnitude

smaller than that measured by Silva et al. for the photolysis of

the

analogous

ruthenium

nitrosyl

complex,

[Ru(tpy)(bpy)(NO)]³⁺(bpy

=

2,2'ꢀbipyridine).²⁷Notably,

exhaustive photolysis led to nearly quantitative conversion to a

spectrum analogous to that of trans-L (L = solvent, see Figure

Table 4. Redox potentials (V vs. Fc/Fc⁺) in acetonitrile for trans-NO₂, cis-NO₂, PP-NO₂, and related compounds at room temperature.

Red.

Ox.

complex

trans-NO₂

cis-NO₂

E(1)

−1.77^b

−1.70

E(2)

E(3)

−2.13^e,g

ꢀ

E(1)

0.79^c,f

0.79

E(2)

0.97^g

−1.99

ꢀ

PP-NO₂

−1.70^b,e

−2.49^g

0.95^c,f

1.27^g

trans-MeCN^a

cis-MeCN^a

PP-MeCN^a

−1.70

−1.77

−2.13

0.97

ꢀ

d

1.05

−1.50

−1.46

−2.49

1.27

[a] Reference 21. [b] These reductions induced the dissociation of NO₂⁻and the formation of MeCNꢀcoordinated species. [c] NO₂was released upon these

oxidation processes, and subsequent coordination of MeCN resulted in the formation of corresponding acetonitrile complexes. [d] cis-MeCN underwent

isomerization to trans-MeCN upon reduction. [e] E_pcvalues for the irreversible processes. [f] E_pavalues for the irreversible processes. [g] Redox processes

correspond to MeCNꢀcoordinated complexes.

6 | J. Name., 2012, 00, 1-3

This journal is © The Royal Society of Chemistry 2012

Page 7 of 13

Journal Name

Dalton Transactions

ARTICLE

of nitritoꢀκ

N

complexes; the bond distances between the

ruthenium and nitrogen atom of the nitrite ligand^Va^ier^we^A2^rt.^ic1^le4^O1ⁿ(3^lin)^e,

DOI: 10.1039/C5DT02994E

2.124 (2), and ca. 2.03 Å for trans-NO₂

respectively. Therefore, the transꢀisomers and PP complexes

exhibited greater lability compared with the corresponding cis

, PP-NO₂, and cis-NO₂,

ꢀ

isomers. Second, the electron donation from labile ligands can

stabilise RuꢀL bonds. The donating ability of labile ligands was

confirmed by the comparison of the HOMO energy levels

obtained from the electrochemical measurements of the cis

ꢀ

isomers and follows the order NO₂^–> MeCN > NO⁺and was in

accordance with the stability of the complexes. Third, oxidation

decreases the electron density of the Ru centre, and the π backꢀ

donating ability of Ru centres should be weakened. DFT

calculations revealed that π backꢀdonation from Ru to the

nitrito ligand occurs and stabilises the RuꢀL bond (Figure S6 in

the ESI). Finally, the reduction of the complexes stabilises the

fiveꢀcoordinated species, as rationalised for the Ru(II)ꢀMeCN

complexes in our previous report.²¹The formation of fiveꢀ

coordinated species in MeCN results in ligand exchange in

Scheme 4 Changes in lability with oxidation or reduction

trans-NO₂and PP-NO₂or isomerisation of cis-MeCN to trans

MeCN, whereas no observable chemical process exists in the

case of cis-NO₂trans-MeCN and PP-MeCN. These results

suggest that the (1) number and position of P atom(s), (2)

coordinating ability of the monodentate ligand, and (3)

oxidation state of the complexes are all factors in defining the

lability of complexes.

-

formation of trans-MeCN and PP-MeCN via the dissociation

cis-NO₂with HPF₆afforded the desired cis-NO. However, the

similar reactions of trans-NO₂and PP-NO₂resulted in the

formation of trans-MeCN and PP-MeCN via the dissociation

of a monodentate labile ligand, N(O)OH or NO⁺(probably the

former). Second, UVꢀvis absorption spectroscopy revealed that

,

the nitrito ligands of trans-NO₂, cis-NO₂, and PP-NO₂did not

dissociate, even in strongly coordinating solvents such as

acetonitrile, whereas ligand exchange reactions of trans-MeCN

and PP-MeCN easily occurred under analogous conditions

(Figure S14 in the ESI). cis-NO was not stable in coordinating

solvent and was easily converted to a solventꢀcoordinated form

(Figure S4 in the ESI).

The difference in lability of the oxidised and reduced state

can also be clarified by the results of the electrochemical

measurements. In the oneꢀelectron oxidised states, trans-NO₂

and PP-NO₂were labile and were converted to the solventꢀ

coordinated forms, trans-MeCN and PP-MeCN, respectively.

By contrast, cis-NO₂was inert during the oxidation process,

Conclusions

This study describes the syntheses, crystal structures and

spectroscopic and electrochemical properties of a series of

phosphineꢀsubstituted ruthenium(II) polypyridine complexes

with nitrogen oxides. Three nitritoꢀκ

cis-NO₂, and PP-NO₂were synthesised by the reaction of the

corresponding acetonitrile complex with NaNO₂in an

ethanol/water mixed solution, and a nitrosyl complex, cis-NO

was obtained by the reaction of cis-NO₂with HPF₆in acetone.

Crystallographic, spectroscopic, and electrochemical analyses

N complexes, trans-NO₂,

,

for these complexes revealed that the

accepting characters of the phosphine ligands clearly affected

the d and d orbitals of the ruthenium centre, respectively.

σꢀdonating and πꢀ

and

a

reversible redox wave was observed in the

σ

π

electrochemical measurement. Similarly, in the reduced states,

the nitrito ligands of trans-NO₂, and PP-NO₂easily dissociated,

although cis-NO₂was stable during the whole electrochemical

process. However, this stability of cis-NO₂was quite different

from that of cis-MeCN: the acetonitrile ligand of cis-MeCN

became labile upon reduction, and the dissociation of the ligand

The investigation of the substitution lability of the monodentate

ligand of each complex suggested that the (1) number and

position of the phosphine groups, (2) coordinating ability of

monodentate ligand, and (3) oxidation state of the metal centre

are all factors in determining the lability of the complex. As a

further extension of our studies, investigations on various

catalytic and photoꢀinduced reactions of the phosphineꢀ

substituted ruthenium(II) polypyridine complexes are in

progress in our laboratories.

resulted in the isomerisation of cis-MeCN to trans-MeCN ²¹

.

The stability of the monodentate labile site for each complex is

shown in Scheme 4.

The difference in the lability of these complexes can be

explained by considering the following factors. First, the σꢀ

donor character of phosphine group significantly elongates the

bond length between the ruthenium centre and the ligand trans

to the phosphine group. This trans influence of the phosphine

group was clearly observed in the Xꢀray structure for the series

Experimental

Materials

This journal is © The Royal Society of Chemistry 2012

J. Name., 2012, 00, 1-3 | 7

Dalton Transactions

Page 8 of 13

Journal Name

ARTICLE

NaNO₂was purchased from Kanto Chemical Co., Inc. NH₄PF₆NMR (CD₃CN):

and HPF₆were purchased from Wako Pure Chemical Industries, Hz), 7.14 (t, 2H,

δ

J

6.56 (t, 2H,

= 7.0 Hz), 7.21 (t, 2H,

= 8.0 Hz),_D7_O.9_I:1₁₀(_.m₁₀,₃^V₉3^ie_/H^w_C)₅^A,_D^rt8ⁱ_T^c.₀^le0₂^O3₉ⁿ₉(^li₄ⁿd_E^e,

= 7.5 Hz), 8.23 (d, 2H, = 8.0

= 7.0 Hz), 8.75 (d, 1H, = 8.0 Hz), 9.93 (d,

J

= 9.0 Hz), 6.98 (t, 4H,

J = 7.0

J

= 8.0 Hz), 7.65 (d,

Ltd. All solvents and reagents were of the highest quality 2H,

available and were used as received. trans(P,MeCN)ꢀ and 2H,

J

= 5.0 Hz), 7.80 (t, 2H,

= 8.0 Hz), 8.09 (t, 1H,

J

cis(P,MeCN)ꢀ[Ru(trpy)(Pqn)(MeCN)](PF₆)₂(trans-MeCN and Hz), 8.46 (d, 1H,

J

cis-MeCN), and [Ru(trpy)(dppbz)(MeCN)](PF₆)₂(PP-MeCN

were prepared following methods found in the literature.¹⁸

)

1H,

J

= 5.0 Hz). ³¹P{¹H} NMR (CD₃CN):

δ

53.10 (s). FTꢀIR:

ν

_s(NO₂) 1304,

ν

_as(NO₂) 1349 cm^–1. Anal. Found: C, 48.50; H,

3.59; N, 8.22. Calcd for C₃₆H₃₂F₆N₅O_4.5P₂Ru

NO₂·2.5H₂O): C, 48.93; H, 3.65; N, 7.93.

Synthesis of cis(P,NO₂)-[Ru(trpy)(Pqn)(NO₂)]PF₆

NO₂). This complex was prepared from cis-MeCN (26.0 mg,

0.0250 mmol) instead of trans-MeCN by a method similar to

that for trans-NO₂. Yield 19.5 mg (0.0221 mmol, 88%). ESIꢀ

(

trans

-

Measurements

(

cis-

¹H and ³¹P{¹H} NMR spectra were recorded at room

temperature on a JEOL JNMꢀLA500 spectrometer using

tetramethylsilane as an internal reference for the ¹H NMR

spectra and phosphoric acid as an external reference for the

³¹P{¹H} NMR spectra. UVꢀvis absorption spectra were

obtained on a Shimadzu UVꢀ2450SIM spectrophotometer at

room temperature. Elemental analyses were carried out on a

Yanagimoto MTꢀ5 elemental analyser. Infrared data were

TOF

([Ru(trpy)(Pqn)(NO₂)]⁺). H NMR (CD₃CN):

6.5 Hz), 7.06 (m, 1H), 7.4 1 (d, 2H,

MS

(positive

ion,

acetonitrile):

m/z

694

1

δ

6.81 (t, 2H, J =

J

= 5.5 Hz), 7.52 (m, 4H),

= 7.5 Hz), 7.73 (m, 4H), 7.84 (t, 2H, = 8.0 Hz),

= 5.5 Hz), 7.97 (t, 1H, = 7.5 Hz), 8.18 (d, 1H,

7.63 (t, 2H,

7.92 (d, 1H,

J

δ

obtained using

a

PerkinꢀElmer Spectrum 100 FTꢀIR

= 8.0 Hz), 8.23 (d, 1H,

= 8.0 Hz) 8.78 (t, 1H,

J

= 8.0 Hz), 8.36 (m, 3H), 8.55 (d, 2H,

= 8.0 Hz). ³¹P{¹H} NMR (CD₃CN):

spectrometer. ESIꢀTOF mass spectra were recorded on a JEOL

JMSꢀT100LC mass spectrometer. All the ESIꢀTOF mass

spectrometric measurements were recorded in the positive ion

mode at a cone voltage of 20 V. Typically, each sample

solution was introduced in the spectrometer at a flow rate of 10

mL/min using a syringe pump. Cyclic voltammograms were

measured at room temperature on a BAS ALS Model

650DKMP electrochemical analyser in acetonitrile ([complex]

= 0.5 mM; 0.1 M tetraethylammonium perchlorate (TEAP)). A

glassy carbon disk, platinum wire, and Ag/Ag⁺electrode (Ag /

0.01 M AgNO₃) were used as the working, auxiliary, and

reference electrodes, respectively. The redox potentials of the

samples were calibrated against the redox signal for the

ferrocene/ferrocenium (Fc/Fc⁺) couple. The photochemical

experiments shown in Figure 8 were made using a photolysis

apparatus consisting of a LSꢀ2134UTF Nd/YAG laser (Tokyo

Instruments, INC.) with excitation provided by the third

harmonic at λ = 355 nm. The pulse width was 5 ns, the beam

diameter incident on the sample was 6 mm, and the repetition

rate was 5 Hz.

54.06 (s). FTꢀIR:

ν

_s(NO₂) 1286,

ν

_as(NO₂) 1339 cm^–1. Anal.

Found: C, 50.38; H, 3.44; N, 8.19. Calcd for

C₃₆H₂₉F₆N₅O₃P₂Ru (cis-NO₂·H₂O): C, 50.47; H, 3.41; N, 8.18.

Synthesis of cis(P,NO₂)-[Ru(trpy)(Pqn)(NO₂)]BPh₄(cis

-

NO₂’). This complex was prepared by a method similar to that

for cis-NO₂with an excess of NaBPh₄instead of NH₄PF₆. The

product was recrystallised from dichloromethane and a small

amount of acetonitrile/diethyl ether to afford orangeꢀred

crystals of cis-NO₂’. Anal. Found: C, 70.54; H, 4.72; N, 6.92.

Calcd for C₆₀H₄₈BN₅O_2.5PRu (cis-NO₂’·0.5H₂O): C, 70.52; H,

4.73; N, 6.85.

Synthesis of cis(P,NO)-[Ru(trpy)(Pqn)(NO)](PF₆)₃(cis-

NO). cis-NO₂(22.4 mg, 0.0261 mmol) was dissolved in

acetone (1 cm³). An excess of 60% HPF₆acid solution was

added dropwise until the solution changed colour from red to

yellow in an iceꢀwater bath. The resulting yellow solution was

concentrated under reduced pressure, and 10 cm³of diethyl

ether was added to precipitate the product. Yield 27.4 mg

1

(0.0223 mmol, 85%). H NMR (acetoneꢀ

d

₆):

= 6.0 Hz), 7.86 (m, 4H),

= 7.5, 13.0 Hz), 8.42 (t,

= 7.5 Hz), 8.49 (m, 2H), 8.55 (m, 1H), 8.80 (d, 1H,

8.0 Hz), 9.01 (m, 3H), 9.10 (m, 1H) 9.22 (m, 3H),. ³¹P{¹H}

NMR (acetoneꢀ ₆): 54.23 (s). FTꢀIR:

_s(NO) 1929 cm^–1. Anal.

δ 7.47 (t, 2H, J =

7.0 Hz), 7.66 (m, 1H), 7.80 (d, 2H,

8.01 (t, 2H, = 7.5 Hz), 8.12 (dd, 4H,

1H,

J

Synthetic procedures

J

J =

Synthesis of trans(P,NO₂)-[Ru(trpy)(Pqn)(NO₂)]PF₆

(

trans-NO₂). A mixture of trans-MeCN (26.8 mg, 0.0252

d

δ

ν

mmol) and NaNO₂(38.8 mg, 0.562 mmol) in ethanol (4

cm³)/water (4 cm³) was heated at 100ºC for 3 hours and then

cooled to room temperature. Acetonitrile (2 cm³) and a NH₄PF₆

(188.4 mg, 1.16 mmol)/water (2 cm³) solution was added to the

abovementioned solution. The resulting red solution was

concentrated to ca. 5 cm³under reduced pressure. The red

product was collected by filtration and washed with water and

diethyl ether. Yield 19.1 mg (0.0216 mmol, 86%). Single red

crystals suitable for Xꢀray crystallography were grown by the

slow diffusion of diethyl ether into a mixture of methanol and a

few drops of acetonitrile solution of trans-NO₂. ESIꢀTOF MS

(positive ion, acetonitrile): m/z 694 ([Ru(trpy)(Pqn)(NO₂)]⁺). ¹H

Found: C, 35.03; H, 2.95; N, 5.59. Calcd for

C₃₆H₄₀F₁₈N₅O_7.5P₄Ru (cis-NO·6.5H₂O): C, 35.16; H, 3.28; N,

5.70.

Synthesis of [Ru(trpy)(dppbz)(NO₂)]PF₆(PP-NO₂). This

complex was prepared from PP-MeCN (31.5 mg, 0.0263

mmol) instead of trans-MeCN by a method similar to that for

trans-NO₂. Yield 22.9 mg (0.0227 mmol, 86%). Single orange

crystals suitable for Xꢀray crystallography were grown through

the slow diffusion of diethyl ether into a mixture of methanol

and a few drops of acetonitrile solution of PP-NO₂. ESIꢀTOF

MS

(positive

ion,

acetonitrile):

m/z

6.50 (m, 4H),

827

([Ru(trpy)(dppbz)(NO₂)]⁺). ¹H NMR (CD₃CN):

δ

8 | J. Name., 2012, 00, 1-3

This journal is © The Royal Society of Chemistry 2012

Page 9 of 13

Journal Name

Dalton Transactions

ARTICLE

6.78 (m, 2H), 6.88 (m, 4H), 7.08 (d, 2H,

J

= 5.5 Hz), 7.17 (m, simulated spectrum of each species, transition energies and

Gaussian

2H), 7.45 (t, 4H, = 7.5 Hz), 7.61 (m, 7H), 7.77 (m, 3H), 7.87 oscillator strengths were interpolated by

J

a

View Article Online

(t, 1H,

J

= 7.5 Hz), 8.03 (d, 2H, J = 8.0 Hz), 8.23 (m, 3H), 8.39 convolution with a common σ value of 0.2 eV.

DOI: 10.1039/C5DT02994E

= 7.5 Hz). ³¹P{¹H} NMR (CD₃CN):

δ

62.65 (d, ²J_P−P

_s(NO₂) 1311,

=

2

14.2 Hz), 68.59 (d, J_P−P= 14.2 Hz). FTꢀIR:

ν

Quantum Yield Measurements

ν

_as(NO₂) 1354 cm^–1. Anal. Found: C, 53.62; H, 4.05; N, 5.46.

Calcd for C₄₅H₃₉F₆N₄O₄P₃Ru (PP-NO₂·2H₂O): C, 53.63; H, Nitric oxide was detected and analysed using a GE Sievers

3.90; N, 5.56.

model 280i nitric oxide analyser (NOA).³⁸Known volumes of

the gases from the solution headspace were injected into the

NOA purge vessel, and these gases were entrained to the

detector using helium or medical grade air. The NO present in

the sample was quantiﬁed using a calibration curve generated

from the reaction of NaNO₂with acidic KI. Chemical

actinometry was performed with ferric oxalate solutions.³⁹The

photolysis source was the output from a 200 W highꢀpressure

mercury lamp passed through an IR filter and collimated with

lenses. An appropriate interference filter was used to select the

X-ray crystallography

The Xꢀray data collection and processing was performed on a

Kappa APEX II CCDC diffractometer by using graphiteꢀ

monochromated MoꢀKα radiation (0.71075 Å) for trans-NO₂

and PP-NO₂. Singleꢀcrystal Xꢀray diffraction measurement of

cis-NO₂’ was performed with a RAXISꢀRAPID Imaging Plate

diffractometer equipped with confocal monochromated MoꢀKα

(0.71075 Å) radiation, and the data were processed using

RAPIDꢀAUTO (Rigaku). The structure was solved by the direct

method using SIRꢀ92²⁸and refined on F²with the fullꢀmatrix

least squares technique using SHELXLꢀ2014.²⁹All nonꢀ

hydrogen atoms were refined anisotropically. Molecular

graphics were generated using ORTEPꢀ3 for Windows³⁰and

desired λ_irr. A shutter shielded the sample from the arc lamp. A

sample of known volume in a 1 cm square cuvette with a

magnetic stirring bar was irradiated for determined time

periods.⁴⁰The NO quantum yields (

Φ_NO) were calculated based

on the nitric oxide release measured using the NOA.

POVꢀRAY ³¹

structure refinement parameters is given in Table 1.

.

A summary of the crystallographic data and

Acknowledgements

The crystallographic data have been deposited at the Cambridge This work was supported by a GrantꢀinꢀAid for Young

Crystallographic Data Centre: Deposition numbers CCDC Scientists (A) (No. 25708011) (to S.M.), a GrantꢀinꢀAid for

1040452, 1040453, and 1040454 for trans-NO₂

, cis-NO₂’, and Challenging Exploratory Research (No. 26620160) (to S.M.),

PP-NO₂, respectively. Copies of the data can be obtained free and a GrantꢀinꢀAid for Young Scientists (B) (No. 24750140) (to

of charge via www.ccdc.cam.ac.uk/data_request/cif.

M.K) from the Japan Society for the Promotion of Science.

This work was also supported by a GrantꢀinꢀAid for Scientific

Research on Innovative Areas "AnApple" (No. 25107526).

DFT calculations

Calculations were performed using the DFT method Studies at UCSB were supported by a US National Foundation

implemented in the Gaussian 09 package.³²The structures were Grant (CHEꢀ1058794 and CHEꢀ1405062)

We thank Dr. Guang

.

fully optimised using the hybrid B3LYP method, which uses Wu of UCSB for the Xꢀray diffraction studies and Dr. John

Becke's threeꢀparameter exchange functional³³with the Garcia of UCSB for confirming photochemical results.

correlation energy functional of Lee, Yang, and Parr.³⁴All

calculations were performed using the standard doubleꢀζ type Notes and references

a

LANL2DZ basis set^35aꢀcor SDD basis set^35dimplemented in

Gaussian 09, without adding any extra polarisation or diffuse

Institute for Molecular Science (IMS), 5ꢀ1 Higashiyama, Myodaiji,

Okazaki, Aichi 444ꢀ8787, Japan. Eꢀmail: masaoka@ims.ac.jp; Fax: +81ꢀ

564ꢀ59ꢀ5589

b

functions. The LANL2DZ basis set also uses a relativistic

effective core potential (RECP) for the Ru atom to account for

the scalar relativistic effects of the inner 28 core electrons

([Ar]3d¹⁰). All calculations were performed using the

polarisable continuum model (PCM)³⁶to compute the

structures in acetonitrile media. All stationary points were

characterised as minima of the potential energy surface by their

harmonic vibrational frequencies. The free energies at 298 K

and 1 atm were obtained through thermochemical analysis of

the frequency calculation using the thermal correction to Gibbs

free energy as implemented in Gaussian 09. The excited states

were calculated using the TDDFT³⁷method within the Tammꢀ

Dancoff approximation as implemented in Gaussian 09. These

calculations employ the hybrid B3LYP functional along with

the basis sets described above. A minimum of 100 excited

states was computed in each calculation. To obtain the

Department of Structural Molecular Science, School of Physical

Sciences, SOKENDAI (The Graduate University for Advanced Studies),

Shonan Village, Hayamaꢀcho, Kanagawa 240ꢀ0193, Japan.

c

ACTꢀC, Japan Science and Technology Agency (JST), 4ꢀ1ꢀ8 Honcho,

Kawaguchi, Saitama, 332ꢀ0012, Japan.

^dResearch Center of Integrative Molecular Systems (CIMoS), Institute for

Molecular Science, 38 Nishigoꢀnaka, Myodaiji, Okazaki, Aichi 444ꢀ8585,

Japan.

e

Department of Chemistry and Biochemistry, University of California at

Santa Barbara, Santa Barbara, California 93106ꢀ9510, United States

†

Electronic Supplementary Information (ESI) available: [details of any

supplementary information available should be included here]. See

DOI: 10.1039/b000000x/

1. (a) N. Sutin, J. Photochem.

,

1979, 10

,

19–40; (b) K.

Kalyanasundaram, Coord. Chem. Rev., 1982, 46, 159–244; (c) E. S.

Dodsworth, A. B. P. Lever, Chem. Phys. Lett., 1986, 124, 152–158;

(d) A. Juris, V. Balzani, F. Barigelletti, S. Campagna, P. Belser, A.

J. Name., 2012, 00, 1-3 | 9

Dalton Transactions

Page 10 of 13

Journal Name

ARTICLE

von Zelewsky, Coord. Chem. Rev., 1988, 84, 85–277; (e) A. B. P.

Parella, J. BenetꢀBuchholz, M. Poyatos, A. Llobet, J. Am. Chem. Soc.

,

Lever, Inorg. Chem., 1990, 29, 1271–1285; (f) V. Balzani, A. Juris,

Coord. Chem. Rev., 2001, 211, 97–115; (g) D. W. Thompson, J. F.

2006, 128, 5306–5307; (c) Y. Shiota, J. M. Herrera, Gergely Juhász,

T. Abe, S. Ohzu, T. Ishizuka, T. Kojima, K. Yoshizawa,

^{View Article}I^Ono^nlrⁱⁿg^e.

DOI: 10.1039/C5DT02994E

Wishart, B. S. Brunschwig, N. Sutin, J. Phys. Chem. A, 2001, 105

,

Chem., 2011, 50, 6200–6209; (d) T. Kojima, K. Nakayama, K.

8117–8122. (h) S. Campagna, F. Puntoriero, F. Nastasi, G. Bergamini,

Ikemura, T. Ogura, S. Fukuzumi, J. Am. Chem. Soc., 2011, 133,

V. Balzani, Top. Curr. Chem., 2007, 280, 117–214; (i) T. P. Yoon, M.

11692–11700; (e) Z. Hu, H. Du, W.ꢀL. Man, C.ꢀF. Leung, H. Liang,

A. Ischay, J. Du, Nat. Chem., 2010,

2, 527–532; (j) Q. Sun, S.

T.ꢀC. Lau, Chem. Commun., 2012, 48, 1102–1104; (f) Z. Hu, L. Ma,

MosqueraꢀVazquez, Y. Suffren, J. Hankache, N. Amstutz, L. M. L.

J. Xie, H. Du, W. W. Y. Lam, T.ꢀC. Lau, New J. Chem., 2013, 37

,

Daku, E. Vauthey, A. Hauser, Coord. Chem. Rev., 2015, 282–283

,

1707–1710.

87–99.

7. (a) J. J. Concepcion, J. W. Jurss, J. L. Templeton, T. J. Meyer, J. Am.

2. (a) C. D. Clark, M. Z. Hoffman, Coord. Chem. Rev., 1997, 159, 359–

373; (b) L. De Cola, P. Belser, Coord. Chem. Rev., 1998, 177, 301–

346; (c) M. D. Ward, F. Barigelletti, Coord. Chem. Rev., 2001, 216–

217, 127–154; (d) M. H. V. Huynh, D. M. Dattelbaum, T. J. Meyer,

Coord. Chem. Rev., 2005, 249, 457–483. (d) H. Kon, K. Tsuge, T.

Imamura, Y. Sasaki, S. Ishizaka, N. Kitamura, M. Kato, Dalton

Trans., 2008, 1541–1543; (e) A. LavieꢀCambot, C. Lincheneau, M.

Chem. Soc., 2008, 130, 16462–16463; (b) H.ꢀW. Tseng, R. Zong, J. T.

Muckerman, R. P. Thummel, Inorg. Chem., 2008, 47, 11763–11773;

(c) S. Masaoka, K. Sakai, Chem. Lett., 2009, 38, 182–183; (d) M.

Yoshida, S. Masaoka, K. Sakai, Chem. Lett., 2009, 38, 702–703; (e)

S. Romain, L. Vigara, A. Llobet, Acc. Chem. Res., 2009, 42, 1944–

1953; (f) J. J. Concepcion, J. W. Jurss, M. K. Brennaman, P. G.

Hoertz, A. O. T. Patrocinio, N. Y. Murakami Iha, J. L. Templeton, T.

J. Meyer, Acc. Chem. Res., 2009, 42, 1954–1965; (g) L. Duan, L.

Cantuel, Y. Leydet, N. D. McClenaghan, Chem. Soc. Rev., 2010, 39

,

506–515; (f) O. Filevich, B. GarcíaꢀAcosta, R. Etchenique,

Photochem. Photobiol. Sci., 2012, 11, 843–847.

Tong, Y. Xu, L. Sun, Energy Environ. Sci., 2011,

4, 3296–3313; (h)

D. J. Wasylenko, R. D. Palmer, C. P. Berlinguette, Chem. Commun.

,

3. (a) F. G. Gao, A. J. Bard, J. Am. Chem. Soc., 2000, 122, 7426–7427;

(b) J. N. Demas, B. A. DeGraff, Coord. Chem. Rev., 2001, 211, 317–

2013, 49, 218–227; (i) M. D. Kärkäs, O. Verho, E. V. Johnston, B.

Åkermark, Chem. Rev., 2014, 114, 11863−12001.

351; (c) P. D. Beer, E. J. Hayes, Coord. Chem. Rev., 2003, 240, 167– 8. (a) H. Yamazaki, T. Hakamata, M. Komi, M. Yagi, J. Am. Chem.

189; (d) R. MartinezꢀMáñez, F. Sancenón, Chem. Rev., 2003, 103 Soc., 2011, 133, 8846–8849; (b) J. L. Boyer, D. E. Polyansky, D. J.

Szalda, R. Zong, R. P. Thummel, E. Fujita, Angew. Chem. Int. Ed.

,

4419−4476; (e) A. S. Polo, M. K. Itokazu, N. Y. M. Iha, Coord.

Chem. Rev., 2004, 248, 1343–1361; (f) M. S. Vickers, K. S.

Martindale, P. D. Beer, J. Mater. Chem., 2005, 15, 2784–2790; (g) N.

,

2011, 50, 12600–12604; (c) S. K. Padhi, R. Fukuda, M. Ehara, K.

Tanaka, Inorg. Chem., 2012, 51, 5386–5392; (d) M. Hirahara, M. Z.

Haddour, J. Chauvin, C. Gondran, S. Cosnier, J. Am. Chem. Soc.

2006, 128, 9693–9698; (h) H. Wei, E. Wang, Trends Anal. Chem.

,

Ertem, M. Komi, H. Yamazaki, C. J. Cramer, M. Yagi, Inorg. Chem.

2013, 52, 6354–6364.

,

2008, 27, 447–459; (i) J. L. Delaney, C. F. Hogan, J. Tian, W. Shen, 9. (a) K. Tanaka, D. Ooyama, Coord. Chem. Rev., 2002, 226, 211–218;

Anal. Chem., 2011, 83, 1300–1306.

(b) J.ꢀM. Savéant, Chem. Rev., 2008, 108, 2348–2378; (c) Y.

Tsukahara, T. Wada, K. Tanaka, Chem. Lett., 2010, 39, 1134–1135;

(d) K. Kobayashi, T. Kikuchi, S. Kitagawa, K. Tanaka, Angew. Chem.

Int. Ed., 2014, 52, 1–6.

4. (a) G. J. Wilson, A. Launikonis, W. H. F. Sasse, A. W.ꢀH. Mau, J.

Phys. Chem. A, 1997, 101, 4860–4866; (b) J. A. Simon, S. L. Curry,

R. H. Schmehl, T. R. Schatz, P. Piotrowiak, X. Jin, R. P. Thummel, J.

Am. Chem. Soc., 1997, 119, 11012–11022; (c) A. D. Guerzo, S. 10. (a) Z. Chen, C. Chen, D. R. Weinberg, P. Kang, J. J. Concepcion, D.

Leroy, F. Fages, R. H. Schmehl, Inorg. Chem., 2002, 41, 359–366;

(d) D. S. Tyson, C. R. Luman, X. Zhou, F. N. Castellano, Inorg.

Chem., 2001, 40, 4063–4071; (e) S. Bernhard, J. A. Barron, P. L.

Houston, H. D. Abruña, J. L. Ruglovksy, X. Gao, G. G. Malliaras, J.

Am. Chem. Soc., 2002, 128, 9693–9698; (f) S. Welter, K. Brunner, J.

W. Hofstraat, L. D. Cola, Nature, 2003, 421, 54–57; (g) H.

Shahroosvand, P. Abbasi, A. Faghih, E. Mohajerani, M. Janghouri, M.

P. Harrison, M. S. Brookhart, T. J. Meyer, Chem. Commun., 2011, 47

12607–12609; (b) Z. Chen, J. J. Concepcion, M. K. Brennaman, P.

Kang, M. R. Norris, P. G. Hoertz, T. J. Meyer, Proc. Natl. Acad. Sci.

,

USA, 2012, 109, 15606–15611; (c) Z. Chen, P. Kang, M.ꢀT. Zhang, T.

J. Meyer, Chem. Commun., 2014, 50, 335–337; (d) P. Kang, Z. Chen,

A. Nayak, S. Zhang, T. J. Meyer, Energy Environ. Sci., 2014, 7,

4007–4012.

Mahmoudi, RSC Adv., 2014,

5. (a) J. K. Barton, Science, 1986, 233, 727–734; (b) C. Turro, S. H.

Bossmann, Y. Jenkins, J. K. Barton, N. J. Turro, J. Am. Chem. Soc.

4

, 1150–1154.

11. (a) A. Kobayashi, R. Takatori, I. Kikuchi, H. Konno, K. Sakamoto, O.

Ishitani, Organometallics, 2001, 20, 3361–3363; (b) A. Kobayashi, H.

Konno, K. Sakamoto, A. Sekine, Y. Ohashi, M. Iida, O. Ishitani,

Chem. Eur. J., 2005, 11, 4219–4226; (c) M. Kimura, K. Tanaka,

Angew. Chem. Int. Ed., 2008, 47, 9768–9771; (d) Y. Matsubara, E.

Fujita, M. D. Doherty, J. T. Muckerman, C. Creutz, J. Am. Chem.

Soc., 2012, 134, 15743–15757; (e) Y. Matsubara, T. Kosaka, K.

Koga, A. Nagasawa, A. Kobayashi, H. Konno, C. Creutz, K.

Sakamoto, O. Ishitani, Organometallics, 2013, 32, 6162–6165; (f) J.

,

1995, 117, 9026–9032; (c) H. B. Gray, J. R. Winkler, Ann. Rev.

Biochem., 1996, 65, 537–561; (d) A. D. Guerzo, A. K.ꢀD. Mesmaeker,

Inorg. Chem., 2002, 41, 938–945; (e) S. Le Gac, M. Foucart, P.

Gerbaux, E. Defrancq, C. Moucheron A. KirschꢀDe Mesmaeker,

Dalton Trans., 2010, 39, 9672–9683; (f) H. Song, J. T. Kaiser, J. K.

Barton, Nat. Chem., 2012,

O’Sullivan, G. Winter, T. Sorensen, J. M. Kelly, C. J. Cardin, Nat.

Chem., 2012, , 621–628; (h) A. C. Komor, J. K. Barton, Chem.

4, 615–620; (g) H. Niyazi, J. P. Hall, K.

Huang, J. Chen, H. Gao, L. Chen, Inorg. Chem., 2014, 53

,

4

9570−9580.

Commun., 2013, 49, 3617–3630.

12. (a) R. W. Callahan, T. J. Meyer, Inorg. Chem., 1977, 574–581; (b) H.

Hadadzadeh, M. C. DeRosa, G. P. A. Yap, A. R. Rezvani, R, J.

Crutchley, Inorg. Chem., 2002, 41, 6521−6526; (c) M. G. Sauaia, R.

6. (a) T. J. Meyer, M. H. V. Huynh, Inorg. Chem., 2003, 42, 8140–

8160; (b) E. Masllorens; M. Rodriguez, I. Romero, A. Roglans, T.

10 | J. Name., 2012, 00, 1-3

Page 11 of 13

Journal Name

Dalton Transactions

ARTICLE

G. de Lima, A. C. Tedesco, R. S. da Silva, J. Am. Chem. Soc., 2003,

125, 14718–14719; (d) Z. N. da Rocha, M. S. P. Marchesi, J. C.

Molin, C. N. Lunardi, K. M. Miranda, L. M. Bendhack, P. C. Ford, R.

S. da Silva, Dalton Trans., 2008, 4282–4287; (e) A. C. Pereira,; P. C.

Ford, R. S. da Silva, L. M. Bendhack, Nitric Oxide, 2011, 24, 192–

198; (f) T. A. Heinrich, A. C. Tedesco, J. M. Fukuto, R. S. da Silva,

D. S. Peterka, R. Yuste, R. Etchenique, J. Inorg. Biochem., 2010, 104,

418–422. (i) S. V. Litke, A. Y. Ershov, T. J. Meyer, J. Phys. Chem. A

,

View Article Online

2011, 115, 14235–14242. (j) V. S. Miguel, M. Álvarez, O. Filevich,

DOI: 10.1039/C5DT02994E

R. Etchenique, A. del Campo, Langmuir, 2012, 28, 1217–1221. (k) R.

Araya, V. AndinoꢀPavlovsky, R. Yuste, R. Etchenique, ACS Chem.

Neurosci., 2013, 4, 1163–1167.

Dalton Trans., 2014, 43, 4021–4025; (g) R. G. de Lima, B. R. Silva, 20. (a) M. E. Marmion, K. J. Takeuchi J. Chem. Soc., Dalton Trans.

,

R. S. da Silva, L. M. Bendhack, Molecules, 2014, 19, 9628–9654.

1988, 2385–2391; (b) C. A. Bessel, R. A. Leising, K. J. Takeuchi, J.

13. (a) T. Kinoshita, J. T. Dy, S. Uchida, T. Kubo, H. Segawa, Nat.

Chem. Soc., Chem. Commun., 1991, 833–835; (c) N. D. Schley, G. E.

Dobereiner, R. H. Crabtree, Organometallics, 2011, 30, 4174–4179;

21. G. Nakamura, M. Okamura, M. Yoshida, T. Suzuki, H. D. Takagi, M.

Kondo, S. Masaoka, Inorg. Chem., 2014, 53, 7214–7226.

Photonics, 2013, 7, 535–539; (b) R. Katoh, A. Furube, J. Photochem.

Photobiol. C, 2014, 20, 1–16.

14. (a) R. Noyori, T. Ohkuma, Angew. Chem. Int. Ed., 2001, 40, 40–73;

(b) R. Noyori, Angew. Chem. Int. Ed., 2002, 41, 2008–2022; (c) R. 22. J. Heinecke, P. C. Ford, Coord. Chem. Rev., 2010, 254, 235–247.

Noyori, Adv. Synth. Catal., 2003, 345, 15–32; (d) S. E. Clapham, A. 23. M. T. Gladwin, A. N. Schechter, D. B. KimꢀShapiro, R. P. Patel, N.

Hadzovic, R. H. Morris, Coord. Chem. Rev., 2004, 248, 2201–2237;

(e) A. F. Trindade, P. M. P. Gois, C. A. M. Afonso, Chem. Rev., 2009,

109, 418–514. (f) R. Noyori, Angew. Chem. Int. Ed., 2013, 52, 79–92.

Hogg, S. Shiva, R. O. Cannon III, M. Kelm, D. A. Wink, M. Graham

Espey, E. H. Oldﬁeld, R. M. Pluta, B. A. Freeman, J. R. Lancaster Jr.,

M. Feelisch, J. O. Lundberg, Nat. Chem. Biol., 2005, 1, 308–314.

15. (a) P. Schwab, M. B. France, J. W. Ziller, R. H. Grubbs, Angew. 24. R. A. Leising, S. A. Kubow, K. J. Takeuchi, Inorg. Chem., 1990, 29

Chem. Int. Ed., 1995, 34, 2039–2041; (b) H. Clavier, S. P. Nolan, 4569–4574.

Chem. Eur. J., 2007, 13, 8029–8036; (c) G. C. Vougioukalakis, R. H. 25. P. Singh, J. Fiedler, S. Záliš, C. Duboc, M. Niemeyer, F. Lissner, T.

Grubbs, Chem. Rev., 2010, 110, 1746–1787; (d) J. S. M. Samec, B. K. Schleid, W. Kaim, Inorg. Chem., 2007, 46, 9254–9261.

Keitz, R. H. Grubbs, J. Organomet. Chem., 2010, 695, 1831–1837; 26. (a) D. W. Pipes, T. J. Meyer, Inorg. Chem., 1984, 23, 2466–2472; (b)

,

(e) S. P. Nolan, H. Clavier, Chem. Soc. Rev., 2010, 39, 3305–3316.

16. (a) C. M. Moore, N. K. Szymczak, Chem. Commun., 2013, 49, 400–

402; (b) K.ꢀN. T. Tseng, J. W. Kampf, N. K. Szymczak,

Organometallics, 2013, 32, 2046–2049; (c) K.ꢀN. T. Tseng, A. M.

Rizzi, N. K. Szymczak, J. Am. Chem. Soc., 2013, 135, 16352–16355.

17. (a) D. K. Dutta, B. Deb, Coord. Chem. Rev., 2011, 255, 1686–1712;

W. R. Murphy, Jr., K. J. Takeuchi, M. H. Barley, T. J. Meyer, Inorg.

Chem., 1984, 25, 1041–1053.

27. R. G. de Lima, M. G. Sauaia, D. Bonaventure, A. C. Tedesco, L. M.

Bendhack, R. S. da Silva, Inorg. Chim. Acta, 2006, 359, 2543–2549.

28. A. Altomare, G. Cascarano, C. Giacovazzo, A. J. Guagliardi, J. Appl.

Cryst., 1993, 26, 343–350.

(b) C. S. Yi, J. Organomet. Chem., 2011, 696, 76–80; (c) I. Mellone, 29. G. M. Sheldrick, Acta Crystallogr. Sect. A, 2008, 64, 112–122.

M. Peruzzini, L. Rosi, D. Mellmann, H. Junge, M. Beller, L. 30. L. J. Farrugia, J. Appl. Crystallogr., 1997, 30, 565–566.

Gonsalvi, Dalton Trans., 2013, 42, 2495–2501.

31. T. D. Fenn, D. Ringe, G. A. Petsko, J. Appl. Crystallogr., 2003, 36,

18. (a) R. A. Leising, J. J. Grzybowski, K. J. Takeuchi, Inorg. Chem.,

944–947.

1988, 27, 1020–1025. (b) B. J. Coe, D. W. Thompson, C. T. 32. M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A.

Culbertson, J. R. Schoonover, T. J. Meyer, Inorg. Chem., 1995, 34

,

Robb, J. R. Cheeseman, G. Scalmani, V. Barone, B. Mennucci, G. A.

Petersson, H. Nakatsuji, M. Caricato, X. Li, H. P. Hratchian, A. F.

Izmaylov, J. Bloino, G. Zheng, J. L. Sonnenberg, M. Hada, M. Ehara,

K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y.

Honda, O. Kitao, H. Nakai, T. Vreven, J. A. Montgomery, Jr. J. E.

Peralta, F. Ogliaro, M. Bearpark, J. J. Heyd, E. Brothers, K. N. Kudin,

V. N. Staroverov, T. Keith, R. Kobayashi, J. Normand, K.

Raghavachari, A. Rendell, J. C. Burant, S. S. Iyengar, J. Tomasi, M.

Cossi, N. Rega, J. M. Millam, M. Klene, J. E. Knox, J. B. Cross, V.

Bakken, C. Adamo, J. Jaramillo, R. Gomperts, R. E. Stratmann, O.

Yazyev, A. J. Austin, R. Cammi, C. Pomelli, J. W. Ochterski, R. L.

Martin, K. Morokuma, V. G. Zakrzewski, G. A. Voth, P. Salvador, J.

J. Dannenberg, S. Dapprich, A. D. Daniels, O. Farkas, J. B. Foresman,

3385–3395. (c) L. F. Szczepura, S. A. Kubow, R. A. Leising, W. J.

Perez, M. H. V. Huynh, C. H. Lake, D. G. Churchill, M. R. Churchill,

K. J. J. Takeuchi, Chem. Soc., Dalton Trans.: Inorg. Chem., 1996, 7,

1463–1470. (d) W. J. Perez, C. H. Lake, R. F. See, L. M. Toomey, M.

R. Churchill, K. J. Takeuchi, C. P. Radano, W. J. Boyko, C. A.

Bessel, J. Chem. Soc., Dalton Trans., 1999, 2281–2292. (e) S. B.

Billings, M. T. Mock, K. Wiacek, M. B. Turner, W. S. Kassel, K. J.

Takeuchi, A. L. Rheingold, W. J. Boyko, C. A. Bessel, Inorg, Chim.

Acta, 2003, 355, 103–115. (f) S. Sharma, S. K. Singh, M. Chandra, D.

S. Pandey, J. Inorg. Biochem., 2005, 99, 458–466. (g) C. M. Moore,

N. K. Szymczak, Chem. Commun., 2013, 49, 400–402.

19. (a) B. P. Sullivan, D. J. Salmon, T. J. Meyer, Inorg. Chem., 1978, 17

,

3334–3341. (b) B. P. Sullivan, D. Conrad, T. J. Meyer, Inorg. Chem.,

1985, 24, 3640–3645. (c) J. P. Otruba, G. A. Neyhart, W. J. Dressick,

J. V. Ortiz, J. Cioslowski, D. J. Fox, Gaussian 09 (Revision C.01),

Gaussian, Inc. Wallingford CT, 2010.

J. L. Marshall, B. P. Sullivan, P. A. Watkins, T. J. Meyer, J. 33. A. D. Becke, J. Chem. Phys., 1993, 98, 5648–5652;

Photochem., 1986, 35, 133–153. (d) R. A. Leising, K. J. Takeuchi, 34. C. Lee, W. Yang, R. G. Parr, Phys. Rev. B, 1988, 37, 785–789.

Inorg. Chem., 1987, 26, 4391–4393. (e) R. A. Leising, J. S. Ohman, 35. (a) T. H. Dunning, Jr. P. J. Hay, in Modern Theoretical Chemistry, ed.

K. J. Takeuchi, Inorg. Chem., 1988, 27, 3804–3809. (f) C. A. Bessel,

J. A. Margarucci, J. H. Acquaye, R. S. Rubmo, J. Crandall, A. J.

Jircitano, K. J. Takeuchi, Inorg. Chem. 1993, 32, 5779–5784. (g) M.

R. Churchill, L. M. Krajkowski, M. H. V. Huynh, K. J. Takeuchi, J.

Chem. Crystallogr., 1997, 27, 589–597. (h) M. Salierno, E. Marceca,

H. F. Schaefer, III, Plenum, New York, 1976; (b) P. J. Hay, W. R.

Wadt, J. Chem. Phys., 1985, 82, 270–283; (c) P. J. Hay, W. R. Wadt,

J. Chem. Phys., 1985, 82, 299–310. (d) D. Andrae, U. Haeussermann,

M. Dolg, H. Stoll, H. Preuss, Theor Chim Acta 1990, 77, 123.

J. Name., 2012, 00, 1-3 | 11

Dalton Transactions

Page 12 of 13

Journal Name

ARTICLE

36. M. Cossi, G. Scalmani, N. Rega, V. Barone, J. Chem. Phys., 2002,

117, 43–54.

View Article Online

37. (a) M. E. Casida, C. Jamorski, K. C. Casida, D. R. Salahub, J. Chem.

Phys., 1998, 108, 4439–4449; (b) R. E. Stratmann, G. E. Scuseria, M.

DOI: 10.1039/C5DT02994E

J. Frisch, J. Chem. Phys.

, 1998, 109, 8218–8224; (c) R.

Bauernschmitt, R. Ahlrichs, Chem. Phys. Lett., 1996, 256, 454–464.

38. P. T. Burks, J. V. Garcia, R. GonzalezIrias, J. T. Tillman, M. Niu, A.

A. Mikhailovsky, J. Zhang, F. Zhang, P. C. Ford, J. Am. Chem. Soc.,

2013, 135, 18145−18152.

39. (a) J. G. Calvert, J. N. Pitts, Photochemistry; J. Wiley & Sons: New

York, 1967; pp 783−786. (b) G. Malouf, P. C. Ford, J. Am. Chem.

Soc., 1977, 99, 7213−7221.

40. C. F. Works, C. J. Jocher, G. D. Bart, X. Bu, P. C. Ford, Inorg.

Chem., 2002, 41, 3728−3739.

12 | J. Name., 2012, 00, 1-3

Page 13 of 13

Dalton Transactions

Journal Name

RSCPublishing

View Article Online

DOI: 10.1039/C5DT02994E

ARTICLE

Graphical Abstract

Four novel phosphineꢀsubstituted ruthenium(II)

polypyridine complexes with nitrogen oxides were

synthesised and structurally characterized by singleꢀ

crystal Xꢀray structural analysis. The substitution

lability of the nitrogen oxide ligand of each complex

is discussed in comparison with that of the

corresponding acetonitrile complexes.

J. Name., 2013, 00, 1-3 | 13

Article Doi

Syntheses and properties of phosphine-substituted ruthenium(II) polypyridine complexes with nitrogen oxides

DOI: 10.1039/c5dt02994e

Source and publish data:

Authors:

Article abstract of DOI:10.1039/c5dt02994e

Full text of DOI:10.1039/c5dt02994e

Products guided by the article

R&D Labs maybe for 10102-43-9

Relevant to this article

Hot Product