Oxidation studies on mustard gas, and the first crystal structure of a metal-mustard gas complex

Article abstract of DOI:10.1016/j.ica.2018.05.012

Attempts to selectively oxidize mustard gas [(ClCH₂CH₂)₂S, abbreviated as BCES] to the non-toxic sulfoxide using a trans-Ru(TMP)(O)₂/O₂ catalyst (TMP = porphyrin dianion of 5,10,15,20-tetramesitylporphyrin) have led to isolation and characterization, including an X-ray structure, of trans-Ru(TMP)(BCES)₂, the first such report of a metal-mustard gas complex.

Full text of DOI:10.1016/j.ica.2018.05.012

Accepted Manuscript
Research paper
Oxidation studies on mustard gas, and the first crystal structure of a metal-mus-
tard gas complex
Nimal Rajapakse, Shahram Mehraban, Andrew Pacheco, Brian O. Patrick, Brian
R. James
PII:
S0020-1693(18)30485-7
https://doi.org/10.1016/j.ica.2018.05.012
ICA 18263
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Please cite this article as: N. Rajapakse, S. Mehraban, A. Pacheco, B.O. Patrick, B.R. James, Oxidation studies on
mustard gas, and the first crystal structure of a metal-mustard gas complex, Inorganica Chimica Acta (2018), doi:
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Oxidation studies on mustard gas, and the first crystal structure of a
metal-mustard gas complex
Nimal Rajapakse, Shahram Mehraban, Andrew Pacheco, Brian O. Patrick, Brian R. James*
Department of Chemistry, University of British Columbia, Vancouver, BC, Canada V6T 1Z1
ABSTRACT
Attempts to selectively oxidize mustard gas [(ClCH2CH2)2S, abbreviated as BCES] to the non-
toxic sulfoxide using a trans-Ru(TMP)(O)2/O2 catalyst (TMP = porphyrin dianion of 5,10,15,20-
tetramesitylporphyrin) have led to isolation and characterization, including an X-ray structure, of
trans-Ru(TMP)(BCES)2, the first such report of a metal-mustard gas complex.
Keywords: Mustard Gas; Ruthenium porphyrins; Oxidations; X-ray structure
1. Introduction
About 30 years ago, reports from our group [1,2] presented studies on the catalyzed O2-
oxidation of thioethers to the sulfoxide, an industrial important process [3]. RuII-porphyrins were
used as catalysts, and two very different mechanistic pathways were established depending on
the porphyrin used, specifically OEP and TMP (the respective dianions of 2,3,7,8,12,13,17,18-
octaethylporphyrin, and 5,10,15,20-tetramesitylporphyrin) [1,2,4,5]. The mechanism using the
bis(thioether) species, Ru(OEP)(R2S)2 [6], involves a suggested initial 1e, ‘outer-sphere’
activation of O2, with formation of RuIII and superoxide that with acid (either added or present as
impurity H2O) forms the HO2 radical that disproportionates into H2O2 and O2; the H2O2 oxidizes
the thioether to sulfoxide and the co-product H2O then reduces the RuIII back to RuII with co-
production of the sulfoxide and the regeneration of the H+ co-catalyst [1,2]. The use of TMP (or
OCP, the 5,10,15,20-tetra(2,6-dichlorophenyl)porphyrin dianion  see Fig.1) allowed for more
’sterically hindered’ species, including formation (using O2) of the corresponding trans-dioxo
species RuVI(porp)(O)2 [4,5] rather than the relatively inert, catalytically inactive, RuIV-O-RuIV
species readily generated from OEP species [2]. These dioxo species are unique in being able to
transfer catalytically both oxo ligands as O-atoms to organic substrates, including some
thioethers [4]; such oxygenations have been well reviewed [7].
*Corresponding author. Tel.: +1 604 822 6645; fax: +1 604 822 2847.
E-mail address: brj@chem.ubc.ca (B.R. James).
1

During our studies on the oxidation of thioethers to sulfoxides [1,2,4], we were contacted by
the Canadian Department of Defence, and received contract grants to investigate whether such
chemistry was applicable to ‘Mustard Gas’ [bis(-chloroethyl) sulfide, abbreviated as BCES];
this is a treacle-like liquid, whose vapour is toxic. The key factor is that the sulfoxide
(ClCH2CH2)2SO is crystalline and as such is essentially non-toxic, while further oxidation
generates the vesicant toxic sulphone [8]. Our studies ended in 1993, and reviews and new
studies on reactivity of BCES, the simulant 2-chloroethyl(ethyl)sulfide (CEES), and other
models, continue to appear [9,10]; metal-organic framework systems are becoming increasingly
involved [10a,b], and include studies on catalyzed selective oxidations to the sulfoxides [10b].
Our paper here describes attempted oxidations of
BCES and CEES using the RuVI(porp)(O)2
Y
species, and includes the first X-ray structure of a
X
transition metal coordination compound with
X
X
BCES, namely Ru(TMP)(BCES)2; this structure
has been mentioned, but only in a short sentence
within two reviews [7a,7c]. As well as the
originality of our structure, the crystal data could
be of value in MOF work. The general types of
Ru-species discussed are shown in Fig.1, where L
= oxo, thioether, or sulfoxide; for TMP, X = Y =
Me, and for OCP, X = Cl, Y = H.
Y
N
L
Ru
L
N
X
X
N
N
X
X
Y
X
Y
Fig.1. Ru(porp)L2 species
2. Experimental
2.1. General
The thioethers Et2S and CEES, thiodiglycol, SOCl2, acetone, acetonitrile, and other common
chemicals (all Aldrich products), and the deuterated solvents acetone-d6 and C6D6 (from MSD
Isotopes), were used as received. The Ru source was obtained on loan from Johnson, Matthey
Ltd. as RuCl3•3H2O (~40% Ru), and the H2(TMP) and H2(OCP) porphyrins were kindly
provided by D. Dolphin of this department.
1H and 13C{H} NMR spectra were measured on a Varian XL-300 or a Bruker AC200F
spectrometer, with residual solvent peaks being used as internal standards.
2.2. BCES (Mustard Gas)
Small amounts of BCES (~1-2 mL) were prepared as needed, by updating an early procedure
[11], and handled with extreme care in a fume-hood. The 2-stage synthesis is shown in Eq. (1);
2

thiodiglycol (2 mL, 2 x 10-2 mol) was stirred with SOCl2 (3 mL, 4 x 10-2 mol) at r.t. (room
temperature, ~20C) for ~15 min., the completion of reaction being checked by 1H NMR. The
-SO2
-2 HCl
S[CH2)2OH]2 + 2 SOCl2
S[CH2)2OS(O)Cl]2
S[(CH2)2Cl]2
(1)
crude product mixture was then placed under vacuum for 15 min to remove gaseous by-products
and any remaining SOCl2; a GC trace in CH2Cl2, showed no impurities in the resulting oily
1
13
BCES. H NMR data in C6D6, and in (CD3)2CO, are given in Table 1; C{1H} (C6D6):  34.4
(C-Cl), 43.0 (C-S). All glass-wear contaminated with BCES was soaked in a bleach solution
(2.5% NaOCl) for at least 24 h before washing; the gloves used were soaked overnight in bleach
and then discarded.
2.3. Sulfoxides and sulfones
BCESO and CEESO. H2O2 (5 mL of 30% aq.) was stirred with BCES (1 mL) in acetone (10
mL) at r.t. for 20 min; on removal of the acetone under reduced pressure, BCESO precipitated as
1
a white crystalline solid (~ 0.7 g, ~ 40% yield; m.pt. 110-111C). H NMR data are given in
Table 1; 13C(1H} (C6D6):  36.8 (C-Cl), 54.5 (C-S). CEESO was made the same way using
1
CEES (1 mL), the product being a liquid at r.t. H NMR data are given in Table 1; 13C{1H}
(C6D6): 43.2 (Cl-C), 33.9 (Cl-C-C), 26.1 (C-CH3), 14.8 (CH3).
BCESO2 and CEESO2. BCES was added to 1.0 mL of acetone-d6 to a concentration of about
5 x 10-2 M), in a 2 mL screw-cap vial, and an ozone/dioxygen mixture (~2-3 % in O3) from a
ozonator (Welsbach Model T-23) was bubbled through the solution at 0.57 L min-1, using a
disposable, 15 cm pasture capillary pipette (attached to the outlet tube of the ozonator); the
pipette was inserted to reach the bottom of the vial to maintain a constant flow. The
compositions of the resultant mixtures (sulfide, sulfoxide, and sulfone) were readily determined
1
by a sampling technique using the ratio of integration intensities of H NMR signals; the same
procedure was used for O3-oxidation of CEES. The 1H NMR data for both sulfones are given in
Table 1. Further kinetic details on the ozone oxidation of BCES and CEES, as well as dibenzyl-
and methyl-p-tolyl sulfides, are available [12].
2.4. Ruthenium complexes
The crystallographically characterized Ru(TMP)(MeCN)2 was made as reported by photolysis
of Ru(TMP)CO in MeCN [4b]; heating the MeCN species under vacuum generates the 4-
coordinate Ru(TMP) that under O2 then forms the isolable Ru(TMP)(O)2 [4a,5b,13]. Various
3

Ru(TMP)L2 species were readily made in situ by addition of excess L (thioethers and their
respective sulfoxides) to the bis-MeCN precursor at NMR concentrations (~10-2 M) in C6D6
1
under either N2. H NMR data for the in situ species are given in Table 2; assignments for the
Ru(TMP)L2 species, where L = thioether, or S- and O-bonded sulfoxide (written as S- and O-),
are based on those established for the L = Et2S, nBu2S, (decylmethyl)2S, and Ph2S systems [2,4].
A small amount (~10 mg) of Ru(TMP)(CEESO)2 (Table 2) was also isolated on one occasion by
treatment of Ru(TMP)(MeCN)2 with excess CEESO in C6H6 solution, followed by column
chromatography to remove excess sulfoxide. Calc.(found) : C, 66.08(66.2); H, 6.06 (6.1); N,
4.82 (4.7); S, 5.51 (5.5).
Crystals of Ru(TMP)(BCES)2 were grown by slow diffusion of CH2Cl2, layered on the C6H6
solution of the in situ species that, like the CEES analogue, was stable toward O2.
2.5. Reactions of BCES and CEES with Ru(porp)(O)2 species
To a C6D6 solution of Ru(TMP)(O)2 (3 x 10-3 M) under 1 atm O2 at r.t. was added excess
1
CEES or BCES (~5 x 10-2 M), and changes were monitored by H NMR; the solutions were
sometimes heated to 35C. The corresponding reactions were carried out using Ru(OCP)(O)2.
1
The H NMR data for Ru(OCP)L2 species (L = BECSO, CEESO), listed in Table 3, were
similarly recorded from reactions of the thioethers with Ru(OCP)(O)2 (see Results and
discussion).
2.6. X-Ray Crystallographic analysis
The crystallographic data for Ru(TMP)(BCES)2 were collected at r.t. on a Rigaku AFC6S
diffractometer with graphite monochromated Cu-K radiation. The intensities of the standard
reflections, taken every 400 reflections, remained constant, and thus no decay correction was
applied. The structure was solved by conventional heavy atom methods [14] and expanded using
Fourier techniques [15]. Refinements were carried out using teXsan [16]. All non-H-atoms were
refined anisotropically, while all H-atoms were fixed in calculated positions with CH = 0.98 Å.
The material crystallizes with two crystallographically independent half-molecules in the
asymmetric unit, with each Ru-atom residing on a different inversion center. Additionally, the
material crystallized as a 1:1 solvate with CH2Cl2. Further details of the structure analysis are
given in a supplementary attachment (SI-1), while all the crystallographic data are available free
of charge as the CCDC number 1585855 from The Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/data_request/cif.
4

3. Results and discussion
BCES (Mustard) was synthesized in small amounts by the reaction shown in Eq.(1), and is of
1
high purity based on H and 13C{1H} NMR data. Only one previous publication in 1988 has
1
reported H data, the  values being given as 3.68 (Cl-CH2) and 2.92 (CH2-S) for the neat
compound in the absence of solvent [17]: the multiplicities were not noted but our triplets
measured in acetone-d6 (Table 1) are in excellent agreement and, as expected, are significantly
downfield (~2.5 ppm) from the CH3 triplet of Et2S (Table 1). Our measured two 13C{1H} signals
in acetone-d6 ( 34.4 and 43.0) are within 2 ppm of those reported for neat BCES [17], and for
BCES in DMSO solution [8b]. NMR data are readily available for the simulant CEES (e.g. in
CDCl3 [8a] and in CD3OD [9]), and our 1H data in C6D6 and in acetone-d6 solution (Table 1) are
comparable; the ClCH2 triplet of CEES is again similarly downfield from the CH3 triplet of Et2S.
The exciting finding, an accidental one, was isolation of crystals of Ru(TMP)(BCES)2, whose
structure is illustrated in Fig.2. The structure is the first to show binding of BCES to a transition
Fig. 2. Structure diagram of Ru(TMP)(BCES)2, one centrosymmetric molecule of two in the asymmetric
unit. Selected bond lengths and angles. Bond lengths (Å): Ru1S1, 2.374(1); Ru1N1, 2.040(3);
Ru1N2, 2.057(3); S1C29, 1.794(5); S1C31, 1.807(5); Cl1C30, 1.783(7); C29C30, 1.512(8);
C31C32, 1.467(8); N1C4, 1.375(4); C4C5, 1.406(5); C3C4, 1.439(5); C2C3, 1.350(5); C5C11,
1.502(5); C11C12, 1.398(5); C12C17, 1.511(7). Bond angles (): S1Ru1N1, 94.47(9); S1Ru1N2,
89.86(9); N1Ru1N2, 89.8(1); Ru1S1C29, 108.9(2); Ru1S1C31, 107.3(2); C29S21C31,
101.1(3); Ru1N1C1, 126.6(2); C1N1C4, 106.6; N1C1C2, 109.5; N1C1C10’, 125.7(3);
C2C1C10’, 124.8(3); C1C2C3, 107.2(4); N1C4C3, 109.2(3); N1C4C5, 125.8(3); C3C4C5,
125.0(3); C4C5C11, 116.6(3); C5C11C12, 121.1(4); C11C12C13, 119.8(4).
5

metal; selected bond lengths and angles are given in the figure legend. No other
Ru(TMP)(thioether)2 crystal structure has been reported, structures containing Ru(TMP) being
limited to species with the axial ligands (MeCN)2 [4b], (OCHMe2)2 [18], and (THF)(N2) [13].
Averaged bond lengths and angles for the Ru(TMP) moiety within all these complexes show no
unusual features, with the Ru being in an essentially non-distorted porphyrin plane. The
geometry details are similar to those established for other Ru(porp) species with two axial S-
bonded ligands [2,19,20]: the Ru is again in an non-distorted porphyrin plane, and the SRuS
axes are within 5 of orthogonality to this plane. The RuS bond lengths within the BCES
ligands are 2.374 Å, and are essentially the same as those found for the axial thioether ligands in
the Ru(OEP)L2 complexes (L = DecMS and Ph2S), where it was noted that this distance is
exactly the sum of the covalent radii for Ru and S [2]. Axial RuS bond lengths in porphyrin
complexes appear to vary little with substituents on the S-atom (e.g. even within the S-bonded
sulfoxide Ru(OEP)(Et2SO), RuS is 2.319 Å) [19], and even with oxidation state of the Ru (e.g.
in [Ru(OEP)(decMS)2][BF4], where RuS is 2.337 Å [20].
The synthetic oxidations of BCES and CEES to the respective sulfoxides were carried at
using aqueous H2O2 at r.t., the use of H2O2 in acetic acid being noted 100 years ago [21].
Oxidations using O3 in acetone-d6 generated the sulfones in situ, a well-established process [22].
1
The sulfoxides and sulfones are readily identified by H NMR data shown in Table 1 together
with corresponding data for the Et2S species [4a,4b]. The data for the sulfoxides sometimes
reveal the magnetic inequivalence of the CH2 protons, first described for Et2SO [23].
The white crystalline BCESO on storage at r.t. in an N2 glove-box turned (over ~3 months)
into a liquid that contained BCES as the major product (1H NMR data); a minor component was
not identified, but was not the sulfone. When stored in air, BCESO again decomposed to mainly
BCES but much slower than the N2-stored sulfoxide; a similar decomposition to non-specified
products has been noted previously [24], and a BCESO sample heated under vacuum has been
reported to contain BCES and BCESO, but again no sulfone [25]. To the best of our knowledge,
such observations on CEESO, a colourless liquid, have not been reported.
Catalytic O2-oxidations of alkyl and aryl thioethers (without Cl substituents) to the sulfoxides
by O-atom transfer from Ru(porp)(O)2 species are well documented; also well-known are the
methodologies for synthesizing the sulfoxides (R2SO) and sulfones (R2SO2), and the respective
Ru(porp)L2 complexes where L is the O- or S-bonded sulfoxide or sulfone [4,7]. Kinetic and
spectroscopic studies have established the mechanism of Scheme 1 for the stoichiometric
oxidation (under N2) of thioethers by the dioxo species (1) to products of types 2, 3 and 4 [4]. In
the presence of excess R2S under O2, catalysis occurs via reaction of 2 with O2 (at 1 atm), this
6

SR2
fast
SR2
k2
k3
Ru(O)2
Ru(O)(OSR2)
Ru(OSR2)2
Ru(OSR2)(OSR2)
Ru(OSR2)2
k1
1
2
3
4
Scheme 1. Ru = Ru(TMP) (1a) or Ru(OCP) (1b) ; R2 = Et2, nBu2, Me(ndecyl); k1 is a measured 2nd-order rate
constant; k2, k3 are non-measured 1st-order rate constants; O means oxygen-bonded, and S is sulfur-bonded [4,6].
regenerating 1 and free sulfoxide that was present in 2 as labile, oxygen-bonded ligands;
however, the total turn-overs (t.o.) are limited. For example, with Ru(TMP)(O)2, Et2S and 1 atm
O2 at 20 C, the t.o. for formation of Et2SO is ~5 after 20 min, but at this stage the substitution-
inert, S-bonded species 4 is present; at 65 C, a higher t.o. of ~15 is observed, but the porphyrin
ligand within Ru(TMP)(O)2 undergoes degradation [4]. The corresponding OCP system provides
effective catalysis, but again the porphyrin dianion slowly degrades [4b].
The Ru(porp)(O)2 systems were tested as catalysts with CEES and BCES as substrates, using
conditions (in C6D6 solution at r.t. under 1 atm O2) similar to those used for the Et2S systems
[4a], the reactions being monitored by1H NMR. For CEES with 1a, after 24 h only
Ru(TMP)(CEESO)2 (type 2) and Ru(TMP)(CEESO)(CEESO) (type 3) in a 2:1 ratio were seen,
with 2 (also isolated) isomerizing slowly to 3, and after 3 weeks >95% 3 was present. Heating to
35 C for a further week revealed further increase in 3, while type 4, the bis(S-bonded sulfoxide)
made in situ independently from Ru(TMP)(MeCN)2, was never detected (Table 2); about one
equiv. of free CEESO (based on [Ru]) was also observed at this stage. The thioether complex
Ru(TMP)(CEES)2 (Table 2), similarly made in situ, was unreactive toward 1 atm O2 at r.t. over 3
weeks; addition of benzoic acid to this system also did not produce detectable amounts of
CEESO, implying no reactivity via the ‘outer sphere’ mechanism evident in the corresponding
Et2S system (see Introduction).
The reaction of BCES with 1a was also studied. After ~50 h at r.t., NMR data revealed a
composition mixture of 25% 1a, 35% 2, and 40% 3; after ~4 days, 1a was no longer present and
2 and 3 were seen in a 2:3 ratio, the isomerization of 2 to 3 then continuing slowly to a 3:5 ratio
over 20 days. As in the CEES system, Ru(TMP)(BCES)2 and Ru(TMP)(BCESO)2 species (Table
2) were not observed, as proven by their in situ syntheses from Ru(TMP)(MeCN)2.
Ru(TMP)(BCES)2 was also unreactive toward 1 atm O2.
Addition of BCESO to a C6D6 solution of Ru(TMP)(BCES)2 did establish the equilibria
shown in Eqs. (2) and (3), with 1H NMR integration intensities allowing for calculation of K2 as
0.34 (at 20 C). This equilibrium is readily shifted in either direction by changing the
[BCES]/[BCESO] ratio; K1 is too large (> 10) to calculate a more precise value.
7

K1
Ru(TMP)(BCES)2 + BCESO
Ru(TMP)(BCES)(BCESO) + BCES
K2
(2)
(3)
Ru(TMP)(BCES)(BCESO) + BCESO
Ru(TMP)(BCESO)2 + BCES
The Ru(OCP)(O)2 complex (1b in Scheme 1) also reacts with CEES and BECS, but under the
same r.t. conditions used for 1a, only the bis(O-bonded-sulfoxide) complexes (type 2) were
detected after 3h (Table 3). The only change on heating the CEES reaction to 50 C for 48 h was
formation of a trace amount of free CEESO. With the BCES system, 1b was completely
consumed after ~12 h at r.t., and no further changes were observed after heating to 50 C. The
presence of chlorine in BCES and CEES clearly decreases the nucleophilicity of the S-atom to
the extent that no O-atom transfer occurs from the trans-Ru-dioxo species to these thioethers.
Acknowledgements
We thank the Natural Sciences and Engineering Council of Canada for funding, and the
Department of National Defence, Canada, for a contract grant (W7702-9-R152/01-XSG) in
1990-1992; the manuscript is the responsibility of the authors and does not reflect an official
position of the Department of National Defence. We also thank Johnson, Matthey Ltd for the
loan of RuCl3•3H2O.
Appendix A. Supplementary material
SI-1 presents an X-ray Structure Report for trans-Ru(TMP)(BECS)2, and all the
crystallographic data are available free of charge as the CCDC number 1585855 from The
Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
Supplementary data associated with this article can be found, in the online version, at http:…
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(c) S. Popiel, J. Nawala, D. Dziedzic, D. Gordon, B. Dawidziuk, Int. J. Chem. Kinet.
50 (2018) 75-89, and refs. therein.
[11] W. Steinkopf, J. Herold, J.Stohr, Ber. 53 (1920) 1007.
[12] S. Mehraban, B.Sc. thesis, University of British Columbia, Canada, 1992.
[13] M.J. Camenzind, B.R. James, D.Dolphin, J.W. Sparany, J.A. Ibers, Inorg. Chem. 27 (1988)
3054.
[14] PHASE (Patterson Heavy Atom Solution Extractor). J.C. Calbrese, Univ. of Wisconsin-
Madison, Ph.D. Thesis (1972).
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1984/1 Crystallography Laboratory, Toernooiveld, 6525 Ed Nijmegen, Netherlands.
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2669 (1994).
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9

[24] E.E. Reid, Ed. Chemistry of Bivalent Sulfur; Chemical Publishing Co.: New York.1960,
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[25] O.B. Helfrich, E.E. Reid, J. Am. Chem. Soc. 42 (1920) 1208.
10

Graphical Abstract
(CH2)2Cl
Cl(H2C)2
S
N
Ru
N
N
N
S
(CH2)2Cl
Cl(H2C)2
S(CH2CH2Cl)2 = mustard gas
N
N
=
N
dianion of 5,10,15,20-tetramesitylporphyrin
N
11

Highlights : Crystal Structure of Ru-Mustard Gas complex
12

Table 1
1H NMR data (, ppm) at r.t. (~20 C) for some organo-sulfur compounds: (ClCH2CH2)2S
(BCES), ClCH2CH2SCH2CH3 (CEES), (CH3CH2)2S and their sulfoxides and sulfones. 1H signals
are assigned in the order shown in the formulae (i.e. from left to right).
Compound
(ClCH2CH2)2S
(ClCH2CH2)2SO
in C6D6
in (CD3)2CO
3.75 t, 2.98 t
4.00 m, 3.26 m
3.00 t, 2.20 t
3.45 m, 2.15m
3.20 m, 2.05 m
(ClCH2CH2)2SO2
4.05 t, 3.71 t
Compound
ClCH2CH2SCH2CH3
ClCH2CH2S(O)CH2CH3
in C6D6
3.22 t, 2.48 t, 2.05 q, 0.95 t
3.70 m, 2.40 m, 2.00 m, 0.85 t 3.98 m, 3.10 m, 2.75 m, 1.28 t
3.40 m, 2.20m
in (CD3)2CO
3.70 t, 2.87 t, 2.62 q, 1.24 t
ClCH2CH2S(O)2CH2CH3
3.95 t, 3.55 t, 3.18 q, 1.34 t
Compound in (CD3)2CO
(CH3CH2)2S
1.20 t, 2.52 q
(CH3CH2)2SO 1.23 t, 2.72 m and 2.60 m
(CH3CH2)2SO2 1.30 t, 3.02 q
Table 2
1H NMR data in C6D6 at r.t. (~20 C) for axial ligands of Ru(TMP)L2.a
L2
ClCH2
0.82 t
ClCH2CH2
1.44 t
CH2CH3
1.90 q
1.76 m
2.16 m
CH3
(CEESO)2
(CEESO)(CEESO)
0.96 t
1.08 t
1.12 t
(CEESO)2
(CEES)2
(BCESO)2
0.90 t
1.22 t
1.13 t
1.05 m, 1.58 m 1.75 m, 2.05 m 1.00 t
1.40 t
1.88 q
0.96 t
1.68 t
(BCESO)(BCESO) 1.24 t, 1.04 t
1.99 t, 0.97 m,
1.42 m
(BCESO)2
(BCES)2
1.15 t
1.08 t
1.20 m, 1.65 m
1.62 t
a  ranges of 1H singlets for the TMP are: pyrrole-H (8.43-8.60); m-H, 7.2-7.3;
p-Me, 2.43-2.60; o-Me, 1.95-2.20.
13

Table 3
1H NMR data in C6D6 at r.t. (~20 C) for the L ligands of Ru(OCP)L2.a
L
ClCH2 ClCH2CH2 CH2CH3 CH3
CEESO 1.25 t
BCESO 1.14 t
1.18 t
1.40 t
1.66 q 0.90 t
a  1H signals for the OCP are:  8.32 (s, pyrrole), 7.36 (d m-H),
6.92/6.90 (t, p-Me) for CEESO/BCESO species.
14