Synthesis of metathesis catalysts with fluorinated unsymmetrical N,N’-diaryl imidazoline-based NHC ligands

Article abstract of DOI:10.1016/j.jfluchem.2017.06.004

New olefin metathesis catalysts bearing unsymmetrical fluorinated NHC ligands with hexafluoroisopropylmethoxy group in ortho-positions of N-aryl-substituent have been synthesized. The effects of mono-ortho-arylsubstitution and the replacement of para-meth

Full text of DOI:10.1016/j.jfluchem.2017.06.004

Accepted Manuscript
Title: Synthesis of Metathesis Catalysts with Fluorinated
Unsymmetrical N,N’-Diaryl Imidazoline-based NHC ligands
Authors: Salekh M. Masoud, Maxim A. Topchiy, Alexander S.
Peregudov, Thierry Roisnel, Pierre H. Dixneuf, Christian
Bruneau, Sergey N. Osipov
PII:
S0022-1139(17)30145-8
DOI:
Reference:
http://dx.doi.org/doi:10.1016/j.jfluchem.2017.06.004
FLUOR 8994
To appear in:
FLUOR
Received date:
Revised date:
Accepted date:
19-4-2017
2-6-2017
7-6-2017
Please cite this article as: Salekh M.Masoud, Maxim A.Topchiy, Alexander
S.Peregudov, Thierry Roisnel, Pierre H.Dixneuf, Christian Bruneau,
Sergey N.Osipov, Synthesis of Metathesis Catalysts with Fluorinated
Unsymmetrical N,N’-Diaryl Imidazoline-based NHC ligands, Journal of Fluorine
Chemistryhttp://dx.doi.org/10.1016/j.jfluchem.2017.06.004
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Synthesis of Metathesis Catalysts with Fluorinated Unsymmetrical
N,N’-Diaryl Imidazoline-based NHC ligands
Salekh M. Masouda,b, Maxim A. Topchiya, Alexander S. Peregudova, Thierry Roisnelc, Pierre H.
Dixneufb, Christian Bruneaub*, and Sergey N. Osipova*
a A.N. Nesmeyanov Institute of Organoelement compounds, Russian Academy of Sciences, Vavilov
str. 28, 119991, Moscow, Russia, e-mail: osipov@ineos.ac.ru
b
UMR 6226 CNRS-Universitꢀ de Rennes 1, Institut des Sciences Chimiques de Rennes,
Organométalliques: Matériaux et Catalyse, Centre for Catalysis and Green Chemistry, Campus
de Beaulieu, 35042 Rennes, France, e-mail: christian.bruneau@univ-rennes1.fr
c UMR 6226 CNRS-Universitꢀ de Rennes 1, Institut des Sciences Chimiques de Rennes, Centre de
Diffractomꢀtrie X, Campus de Beaulieu, 35042 Rennes, France.
Highlights

Fluorinated unsymmetrical N,N’-diaryl imidazolinium salts as new NHC ligand precursors for olefin
metathesis catalysts.


Synthesis of new ruthenium carbene complexes.
Investigation of catalytic activity of new fluorinated complexes in RCM and CM reactions.
Abstract: New olefin metathesis catalysts bearing unsymmetrical fluorinated NHC ligands with
hexafluoroisopropylmethoxy group in ortho-positions of N-aryl-substituent have been synthesized. The
effects of mono-ortho-arylsubstitution and the replacement of para-methyl N-aryl group with more
electron-donating methoxy group in unsymmetrical fluorinated NHC ligand on the activity of complexes
have been evaluated.
Introduction
Keywords: fluorinated NHC; ; ; , ruthenium complexes, olefin metathesis, catalysis.
N-heterocyclic carbenes (NHCs) have found widespread applications as important auxiliary
ligands in modern organometallic and coordination chemistry [1-7]. Their unique steric and
electronic properties have made possible the development of effective metal catalysts for various
applications with the most outstanding examples in the field of ruthenium-catalyzed olefin
metathesis [8-19]. Ruthenium complexes bearing NHC ligands usually demonstrate their
superiority over first generation catalysts containing classical phosphine ligands exhibiting higher
thermal stability, activity and selectivity (Figure 1) [4,20-23].
Figure 1. Commercially available olefin metathesis catalysts
A major advantage of this class of complexes is a possibility to perform a fine-tuning of their
catalytic properties by modifying the NHC stereoelectronics [24-28]. In this context, the

importance of unsymmetrical N-heterocyclic carbenes (uNHCs) as ligands in metal catalysis is
doubtless, as desymmetrization allows for further fine-tuning. The introduction of functionality,
chelation, chirality, and shielding effects can influence the catalyst stability, reactivity, and
selectivity, thus motivating the exploration of new tailor-made systems [29].
On the other hand, fluorinated compounds have found extensive applications in
pharmaceutical and medicinal chemistry [30-35] or crops [36,37] and material sciences [38,39],
due to the unique physicochemical features of fluorine atoms introduced in organic molecules [40].
In the field of ruthenium-alkylidene complexes, the influence of fluorine and fluorinated groups
on their catalytic properties has been mainly studied by usage of definitely modified phosphine
[41-44], benzylidene [45-56] ligands, as well as by the replacement of one or two chlorine atoms
at ruthenium, for example, with perfluoro-carboxylates [57-61] and -alkoxylates [62,63].
Meanwhile, the number of reports on metathesis catalysts decorated with fluorinated NHC ligands
is extremely limited [64-67]. For instance, Fürstner et al. described an unsymmetrical complex
with C6F13(CH2)2 group at one of the imidazolyl nitrogen to increase the solubility of the catalyst
in supercritical CO2 [68]. In 2006, Grubbs reported rate acceleration in RCM of diethyl
diallylmalonate arising from a Ru···F interaction between one ring of a N,N’-bis(2,6-
difluorophenyl)imidazol-2-ylidene and the metal center in the Grubbs II catalyst analogue [69,70].
This work has been further extended with studies of synthesis and catalytic activities of closely
related non-symmetrical analogues [71,72]. Consequently, the development of new tailor-made
NHCs, particularly fluorinated ones, is highly desirable to enable new transformations or to bring
established reactions into new reaction media.
At the same time, the variation of the substitution pattern in N-aryl moieties of the NHC ligand
led to extremely active catalysts for challenging transformations involving metathesis of hindered
substrates [4,73-76]. However, it is not always easy to predict how structural and electronic
changes at the NHC can affect the catalyst activity. For example, the presence of bulky substituents
on nitrogen has been shown to improve catalyst stability limiting decomposition pathways due to
C-H bond activation of N-aryl rings [77], whereas mono-ortho-substituted N-aryl groups of the
NHC ligand have been recognized as an important feature for successful ring-closing metathesis
(RCM) reactions [78]. On the other hand, N-para-methoxyaryl NHCs [79] have been found to be
excellent ligands for palladium catalysts for Buchwald-Hartwig coupling, compared to the
corresponding parent NHCs [80,81]. Plenio et. al. have recently established that para-
functionalized N-aryl NHC complexes did indeed affect the properties of the transition metal
centre [82]. Later Nolan et. al. have demonstrated that Ru metathesis catalysts bearing
imidazoline-based NHCs with N-para-methoxyaryl moieties were able to increase the initiation
rate in RCM reactions at very low catalyst loadings [83].

Based on our experience in metathesis of different unsaturated fluorine-containing molecules
[84-92], we have recently developed an efficient route to novel type of metathesis catalysts
comprising unsymmetrical imidazolinylidene ligand with hexafluoroisopropylmethoxy
[(CF3)2(OMe)C-] group in one of the N-aryl substituents and have demonstrated their good
performance in ring closing olefin metathesis [93] (1 and 2, Fig. 2). With the aim of evaluating the
effects of mono-ortho-arylsubstitution and the replacement of para-methyl N-aryl group with
more electron-donating methoxy group in unsymmetrical fluorinated NHC ligand on the activity
of the resulting precatalysts, we now want to disclose the synthesis of the corresponding ruthenium
carbene complexes (3-6, Fig. 2) and preliminary evaluation of their catalytic activity as well.
Figure 2
Results and discussion
First, we directed our efforts towards the synthesis of the mono-substituted anilines 10a,b
containing hexafluoroisopropylmethoxy group in the ortho-position. For this purpose the
commercially available para-toluidine and para-anisidine were heated with excess of
hexafluoroacetone (HFA) hydrate under acid catalysis according to previously elaborated for 2,4-
dimethyl derivative protocol [93] to give the corresponding anilines 7a,b in good to excellent
yields. To perform the selective O-methylation, they were first transformed into azides 8a,b via
successive treatments with sodium nitrite and azide, and then, 8a,b were methylated with methyl
iodide under basic conditions to afford O-protected azides 9a,b. Finally, the reduction of azido
group of 9 was performed with sodium borohydride under cobalt dichloride-catalysis in the

presence of cetyltrimethylammonium bromide to stabilize catalytic Co-species leading to excellent
yields of anilines 10a,b (Scheme 1).
(a) HFA·1.5H2O, pTSA, 100 °C, 8 h, (b) NaNO2, H2SO4, 0 °C, NaN3, H2O, rt, 1 h, (c) MeI, K2CO3,
MeCN, rt, 2 days, (d) NaBH4, CoCl2, CTABr, H2O/MeOH, rt, 1 h.
Scheme 1
The anilines 10a,b obtained were further used as the starting materials to construct the desired
imidazolinium salts 16a,b. The synthetic sequence included: (a,b) selective N-acylation with
chloroacetyl chloride with subsequent halogen exchange with NaI to give the iodides 12a,b in very
good yields for both steps; (c,d) condensation with mesitylamine followed by the reduction of the
resulting aminoamides 13a,b with BH3·SMe2 to afford the corresponding diamines 14a,b; and
finally (e,f) selective formylation at the more sterically accessible amino group using acetic-formic
mixed anhydride followed by heterocyclization via the treatment with stoichiometric amounts of
triflic acid (TfOH) and triflic anhydride (Tf2O) to give the target NHC precursors 16a and 16b in
85% and 83% yields, respectively (Scheme 2). The last two steps (e,f) were performed using a
slightly modified procedure previously developed by us for sterically demanding fluorinated
imidazolinium salts [93].

(a) ClCOCH2Cl, AcOH, AcONa, H2O, rt, 10 min, (b) NaI, acetone, rt, 1 day, (c) MesNH2, rt, 4
days, (d) BH3·SMe2, PhMe, 90 °C, 4 h, (e) AcOCHO, DCM, rt, 5 min., (f) 1. TfOH, rt, 2. Tf2O,
65 °C, 3. DIPEA, 80 °C, PhMe, 3 h.
Scheme 2
With these new fluorinated unsymmetrical NHC salts in hand, we prepared the new ruthenium
complexes 3-6 in moderate to good yields following the conventional route including the reactions
of in situ generated carbene with commercially available RuCl2(PCy3)2(=CHPh) G-I [94] and
RuCl2(PCy3)(=CH(o-iPrO-C6H4)) H-I [95]. Purification by silica gel chromatography and further
recrystallization from a DCM/n-pentane mixture afforded dark-brown (3, 4) and dark-green (5, 6)
air stable solids (Scheme 3).
Scheme 3

The complexes obtained were fully characterized by NMR spectroscopy and elemental
analysis. In 1H NMR spectra of both phosphine-containing 3, 4 and phosphine-free 5, 6 complexes
measured at room temperature the absorptions of intrinsic benzylidene protons are observed
around 19.6 ppm and 16.9 ppm, respectively, as two broad singlets in each case. The doubling of
19
the signals for CF3-groups takes place in F NMR spectra also. This phenomenon could be
attributed to the existence of two rotamers due to hindered rotation of bulky fluorinated aryl group
around C-N bond. These doublets come together at 60-70 °C under NMR experiment measured in
13
toluene-d8, which supports the existence of rotamers (see Experimental section). The C NMR
spectrum of the NHC at 60 °C displays a resonance at 220 ppm for the carbene center, which is in
the expected range for aryl-substituted imidazolylidenes (see Experimental section). In addition,
single crystals of good quality for X-ray analysis from complexes 5 and 6 (Fig. 3) were obtained
by slow diffusion of pentane into a concentrated dichloromethane solution.
<InlineShape1>
5
6
Figure 3. Molecular structure of complexes 5 and 6. Thermal ellipsoids are drawn at 30%
probability. Hydrogen atoms are omitted for clarity.
Catalytic activities of the prepared catalysts 3-6 were investigated in RCM reactions with
diethyl diallylmalonate (DEDAM) and in CM reaction of allylbenzene with 1,4-diacetoxybut-2-
ene following standard protocols for evaluation of olefin metathesis catalysts [71,72]. The
commercially available G-II and H-II catalysts along with previously obtained 1 and 2 were used
as reference catalysts to find out how modulating the electronic and steric changes of the
fluoroakyl-substituted aryl ring might affect the catalytic activity.
As a result, we found that initiation rates of the Grubbs type catalyst 3, 4 in RCM of DEDAM
were slightly higher as compared to G-II and 1 (Figure 4). On the other hand, the initiation rates
of Hoveyda type catalysts 5 and 6 have proved to be in between the corresponding H-II and 2 rates
(Figure 5), exhibiting some significant initiation period (about 10 min) before they could achieve
full conversion in longer reaction times (4 h).

In the cross metathesis of allylbenzene with an excess of 1,3-diacetoxybut-2-ene, the
phosphine-containing catalysts 3 and 4 revealed slightly higher reactivity as compared with the
ortho,ortho-disubstituted analogue 1 and close kinetic profiles to G-I catalyst (Figure 6). In the
case of phosphine-free complexes 5 and 6 these differences in catalytic activity did not exist and
the complexes allowed to reach an equilibrium at 70-80% conversion within 30 min (Figure 7).
as compared to 1, G-II and H-II
as compared to 2, G-II and H-II
In all studied reaction, no significant influence of para-methoxyaryl substitution on the
catalytic activity of complexes could be found.
Conclusions
In conclusion, the synthesis of new metathesis catalysts bearing unsymmetrical fluorinated
NHC ligands with hexafluoroisopropylmethoxy group in ortho-position of N-aryl-substituent have
been developed. The effects of mono-ortho-arylsubstitution and the replacement of para-methyl
N-aryl group with more electron-donating methoxy group in unsymmetrical fluorinated NHC
ligand on the activity of complexes have been evaluated. As a result, the performance of the new
Grubbs type catalysts in olefin metathesis has proved to be similar to the classical Grubbs second
generation catalyst. On the other hand, the new Hoveyda type catalysts demonstrate a short latent
character before reaching full conversion in RCM of diallylmalonate in longer period in
comparison to the commercially available Hoveyda-II catalyst equipped with symmetrical H2IMes
carbene ligand. In all cases, the absence of a methyl group at the other ortho-position of the
hexafluoroisopropylmethoxy ortho-substituted aryl group of the unsymmetrical NHC led to faster
initial rates with Grubbs type catalyst (3, 4 as compared to 1) and with Hoveyda type catalysts
after the initiation period was completed (5, 6 as compared to 2).
Acknowledgments
This work was financially supported by the Russian Scientific Foundation (grant RSF № 16-13-
10364). S.M. thanks the RAS and the French Embassy in Moscow for a Ph.D.
Experimental
4.1. General remarks.
All solvents were freshly distilled from appropriate drying agents before use. All other reagents
were recrystallized or distilled as necessary. Syntheses of ruthenium complexes were performed
under an argon atmosphere using a standard Schlenk technique. Analytical TLC was performed

with Merck silica gel 60 F254 plates. Visualization was accomplished by UV light (254 and
366 nm), spraying by Ce(SO4)2 solution in 5% H2SO4 or KMnO4 solution in water. Column
chromatography was carried out using Merck silica gel 60 (230-400 mesh ASTM) and ethyl
acetate/petroleum ether. NMR spectra were recorded, unless otherwise stated, at room temperature
on Bruker AV-300, AV-400, AV-500, AV-600 spectrometers operating at 300, 400, 500, and 600
MHz for 1H; 75, 101, 126, and 151 MHz for 13C; 282, 376, 471, and 564 MHz for 19F (CFCl3 as
reference), and 121, 162, 202, and 243 MHz for 31P (85% H3PO4 as reference). The chemical shifts
are frequency referenced relative to the residual undeuterated solvent peaks.
4.2. General procedure for synthesis of 7.
A mixture of 6-methylaniline or 6-methoxyaniline (46.7 mmol), hexafluoroacetone sesquihydrate
(18.6 g, 112.1 mmol), and PTSA (100 mg, 0.5 mmol) was heated at 100°C for 20 h. After cooling
to r.t., water (50 mL) was added and a resulting mixture was extracted with EtOAc (3×30 mL).
The combined organic layers were washed with H2O and brine and then dried over MgSO4. The
solvent was removed under reduced pressure, and the resulting solid was recrystallized from
petroleum ether to yield a dark solid.
4.2.1. 2-(2-Amino-5-methylphenyl)-1,1,1,3,3,3-hexafluoropropan-2-ol (7a).
1
Yield: 94%; brown solid; mp 110-113°C; H NMR (300 MHz, CDCl3) δ 7.37 (s, 1H), 7.16 (d,
3JH,H = 8.0 Hz, 1H), 6.97 (d, 3JH,H = 8.0 Hz, 1H), 5.57 (br.s, 3H), 2.35 (s, 3H); 13C NMR (75 MHz,
1
2
CDCl3) δ 138.8, 135.3, 131.3, 129.1, 127.4, 123.5 (q, JC,F = 288 Hz), 123.0, 80.0 (p, JC,F = 30
Hz), 21.2; 19F NMR (282 MHz, CDCl3) δ -75.14 (s). Anal. Calcd for C10H9F6NO (%) C, 43.97; H,
3.32; N, 5.13. Found: C, 43.92; H, 3.38; N, 4.90.
4.2.2. 2-(2-Amino-5-methoxyphenyl)-1,1,1,3,3,3-hexafluoropropan-2-ol (7b).
Yield: 71%; black solid; mp 104-107°C; 1H NMR (400 MHz, CDCl3) δ 7.13 (s, 1H), 7.04 (d, 3JH,H
= 8.7 Hz, 1H), 6.90 (dd, JH,H = 8.7, 2.7 Hz, 1H), 6.08 (br.s, 3H), 3.79 (s, 3H); 13C NMR (101 MHz,
1
CDCl3) δ 157.3, 133.6, 129.4, 125.0, 123.4 (q, JC,F = 289 Hz), 115.8, 114.5–114.3 (m), 81.0 –
19
79.0 (m), 55.7; F NMR (376 MHz, CDCl3) δ -75.33 (s). Anal. Calcd for C10H9F6NO2 (%) C,
41.53; H, 3.14; N, 4.84. Found: C, 41.57; H, 3.37; N, 4.65.
4.3. General procedure for synthesis of 8.
To a mixture of aniline 7 (20 mmol) in 60 ml of water concentrated sulfuric acid (10.7 mL,
200 mmol) was slowly added. The resulting mixture was cooled to 0°C and solution of NaNO2
(1.59 g, 23.0 mmol) in 6 mL of water was added dropwise and reaction mixture was stirred in an
ice bath for 30 min. Then solution of NaN3 (1.56 g, 24 mmol) in 6 mL of water was added
dropwise. After full addition the reaction mixture was allowed to stir at r.t. for 3 hours. Then the
reaction mixture was extracted with EtOAc (3×20 mL). Combined organic layer was washed with
brine (20 mL), dried over MgSO4 and concentrated under reduced pressure. The crude product was

purified by flash chromatography using EtOAc/petroleum ether (1:3) as eluent to yield yellowish
crystals.
4.3.1. 2-(2-Azido-5-methylphenyl)-1,1,1,3,3,3-hexafluoropropan-2-ol (8a).
Yield: 95%; mp 64-65°C; 1H NMR (400 MHz, CDCl3) δ 7.44 (s, 1H), 7.33 (d, 3JH,H= 8.2 Hz, 1H),
7.16 (d, 3JH,H = 8.3 Hz, 1H), 7.04 (br.s, 1H), 2.38 (s, 3H); 13C NMR (101 MHz, CDCl3) δ 135.9,
135.4, 132.3, 130.3 (m), 122.7 (q, 1JC,F= 289 Hz), 119.8, 119.7, 79.9 (p, 2JC,F = 30 Hz), 21.2; 19F
NMR (376 MHz, CDCl3) δ -74.88 (s). Anal. Calcd for C10H7F6N3O (%) C, 40.15; H, 2.36; N,
14.05. Found: C, 39.91; H, 2.39; N, 14.19.
4.3.2. 2-(2-Azido-5-methoxyphenyl)-1,1,1,3,3,3-hexafluoropropan-2-ol (8b).
Yield: 88%; mp 67-68°C; 1H NMR (400 MHz, CDCl3) δ 7.19 (d, J = 8.8 Hz, 2H), 7.19 (s, 1H),
7.07 (dd, J = 8.9, 2.7 Hz, 1H), 7.07 (br.s, 1H), 3.82 (s, 3H); 13C NMR (101 MHz, CDCl3) δ 157.1,
1
3
2
130.3, 122.7 (d, JC,F = 289 Hz), 121.0, 120.8, 116.9, 115.8 (p, JC,F = 3 Hz), 79.8 (p, JC,F = 30
Hz), 55.8; 19F NMR (376 MHz, CDCl3) δ -74.94 (s). Anal. Calcd for C10H7F6N3O2 (%) C, 38.11;
H, 2.24; N, 13.33. Found: C, 37.79; H, 2.32; N, 13.45.
4.4. General procedure for synthesis of 9.
A mixture of azide 8 (17.6 mmol), iodomethane (2.2 mL, 35.3 mmol) and anhydrous K2CO3 (4.88
g, 35.3 mmol) in 80 mL of acetonitrile was stirred at r.t. for 2 days. After reaction completion the
solvent was evaporated under reduced pressure, residual solid was dispersed in EtOAc and filtered.
The resulting filtrate was evaporated again and purified by flash chromatography using
EtOAc/petroleum ether (1:8) as eluent to yield yellow oil that was crystallized after complete
removal of solvent under high vacuum.
4.4.1. 1-Azido-2-(1,1,1,3,3,3-hexafluoro-2-methoxypropan-2-yl)-4-methylbenzene (9a).
Yield: 96%; mp 51-52°C; 1H NMR (400 MHz, CDCl3) δ 7.36 (s, 1H), 7.33 (d, 3JH,H = 8.3 Hz, 1H),
3
13
7.21 (d, JH,H = 8.2 Hz, 1H), 3.46 (s, 3H), 2.38 (s, 3H); C NMR (101 MHz, CDCl3) δ 137.2,
135.0, 132.6, 131.8, 122.6 (q, 1JC,F = 292 Hz), 120.7, 118.2, 84.3 (p, 2JC,F = 29 Hz), 54.6, 21.1; 19F
NMR (376 MHz, CDCl3) δ -69.86 (s). Anal. Calcd for C11H9F6N3O (%) C, 42.18; H, 2.90; N,
13.42. Found: C, 42.35; H, 3.11; N, 13.72.
4.4.2. 1-Azido-2-(1,1,1,3,3,3-hexafluoro-2-methoxypropan-2-yl)-4-methoxybenzene (9b).
Yield: 91%; mp 52-53°C; 1H NMR (400 MHz, CDCl3) δ 7.25 (d, 3JH,H = 8.8 Hz, 1H), 7.13 (s, 1H),
13
7.07 (dd, J = 8.8, 2.8 Hz, 1H), 3.83 (s, 3H), 3.48 (s, 3H); C NMR (101 MHz, CDCl3) δ 156.8,
132.2, 122.5 (q, 1JC,F = 291 Hz), 122.0, 119.6, 117.5-117.3 (m), 117.1, 84.9-83.4 (m), 55.8, 54.7;
19F NMR (376 MHz, CDCl3) δ -69.87 (s). Anal. Calcd for C11H9F6N3O2 (%) C, 40.13; H, 2.76; N,
12.76. Found: C, 40.41; H, 2.83; N, 12.97.
4.5. General procedure for synthesis of 10.

The azide 9 (13.8 mmol) was dissolved in 4.3 ml of methanol, then CoCl2·6H2O (290 mg, 1.4
mmol) and cetyltrimethylammonium bromide (CTABr) (426 mg, 1.4 mmol) were added with
stirring at r.t. Then a solution of NaBH4 (1.04 g, 27.6 mmol) in 26 ml of water was added dropwise.
After full addition the reaction mixture was stirred another 30 min and extracted with Et2O (3×15
ml). Combined organic layer was washed with 10 ml of water, filtered through cotton wool and
evaporated under reduced pressure to yield yellow crystals.
4.5.1. 2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methylaniline (10a).
Yield: 98%; mp 61-63°C; 1H NMR (400 MHz, CDCl3) δ 7.09 (s, 1H), 7.06 (d, 3JH,H = 8.3 Hz, 1H),
3
13
6.65 (d, JH,H = 8.2 Hz, 1H), 4.56 (br.s, 2H), 3.56 (s, 3H), 2.26 (s, 3H); C NMR (101 MHz,
3
1
CDCl3) δ 144.1, 132.1, 130.1 (p, JC,F = 2.1 Hz), 127.5, 123.0(q, JC,F = 292 Hz), 118.9, 109.4,
2
19
85.3 (p, JC,F = 28 Hz), 54.8, 20.7; F NMR (376 MHz, CDCl3) δ -69.84 (s). Anal. Calcd for
C11H11F6NO (%) C, 46.00; H, 3.86; N, 4.88. Found: C, 45.92; H, 3.97; N, 5.03.
4.5.2. 2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methoxyaniline (10b).
Yield: 92%; mp 51-53°C; 1H NMR (400 MHz, CDCl3) δ 6.88 (s, 1H), 6.88 (d, 3JH,H = 9.4 Hz, 1H),
3
13
6.69 (d, JH,H = 9.4 Hz, 1H), 4.42 (br.s, 2H), 3.75 (s, 3H), 3.57 (s, 3H); C NMR (101 MHz,
CDCl3) δ 152.1, 140.4, 123.0 (q, 1JC,F = 292 Hz), 120.0, 118.0, 115.3–115.1 (m), 110.3, 85.9–84.3
19
(m), 55.9, 54.9; F NMR (376 MHz, CDCl3) δ -69.87 (s). Anal. Calcd for C11H11F6NO2 (%) C,
43.57; H, 3.66; N, 4.62. Found: C, 43.89; H, 4.01; N, 4.64.
4.6. General procedure for synthesis of 11.
Aniline 10 (10.6 mmol) was added to 6 mL of glacial acetic acid in a round-bottomed flask
followed by chloroacetyl chloride (870 µL, 10.9 mmol) and 10.4 mL of half-saturated aqueous
sodium acetate. Precipitation of the amide was observed in 10 min. The product is stirred
thoroughly with 10 mL of cold water and isolated by filtration. Solid product was dissolved in
ethyl acetate and washed with saturated aqueous NaHCO3 and brine, dried above MgSO4. Then
solvent was removed under reduced pressure, resulting solid residue was recrystallized in
petroleum ether to yield a white solid.
4.6.1. 2-Chloro-N-[2-(1,1,1,3,3,3-hexafluoro-2-methoxypropan-2-yl)-4-methylphenyl]acetamide
(11a).
Yield: 87%; mp 70-71°C; 1H NMR (400 MHz, CDCl3) δ 9.78 (s, 1H), 8.43 (d, 3JH,H = 8.5 Hz, 1H),
7.32 (d, 3JH,H = 8.6 Hz, 1H), 7.29 (s, 1H), 4.19 (s, 2H), 3.54 (s, 3H), 2.37 (s, 3H); 13C NMR (101
MHz, CDCl3) δ 164.0, 134.9, 134.8, 132.2, 130.2 (m), 123.21 (s), 122.5 (q, 1JC,F = 290 Hz), 114.8,
85.1 (p, 2JC,F = 28.6 Hz), 54.7, 43.2, 21.2; 19F NMR (376 MHz, CDCl3) δ -69.57 (s). Anal. Calcd
for C13H12ClF6NO2 (%) C, 42.93; H, 3.33; N, 3.85. Found: C, 43.11; H, 3.67; N, 4.12.
4.6.2.
2-Chloro-N-[2-(1,1,1,3,3,3-hexafluoro-2-methoxypropan-2-yl)-4-
methoxyphenyl]acetamide (11b).

Yield: 99%; mp 101-102°C; 1H NMR (400 MHz, CDCl3) δ 9.62 (s, 1H), 8.41 (d, 3JH,H = 9.9 Hz,
1H), 7.05 (d, 3JH,H = 9.9 Hz, 1H), 7.06 (s, 1H), 4.19 (s, 2H), 3.82 (s, 3H), 3.54 (s, 3H); 13C NMR
1
(101 MHz, CDCl3) δ 163.9, 156.4, 130.1, 125.0, 122.5 (q, JC,F = 289 Hz), 116.7, 116.4–116.1
2
19
(m), 115.9, 84.9 (p, JC,F = 29 Hz), 55.7, 54.8, 43.1; F NMR (376 MHz, CDCl3) δ -69.63 (s).
Anal. Calcd for C13H12ClF6NO3 (%) C, 41.12; H, 3.19; N, 3.69. Found: C, 41.10; H, 3.22; N, 3.43.
4.7. General procedure for synthesis of 12.
Chloroacetamide 11 (9.18 mmol) was dissolved in acetone (90 mL), and then sodium iodide
(3.44 g, 23.0 mmol) was added. The reaction mixture was stirred at r.t. for 24 h. After filtration,
the mother liquor was concentrated, and the residue was dissolved in EtOAc (20 mL) and washed
with a 5% solution of Na2S2O3 (10 mL). The organic layer was separated, and the aqueous layer
was extracted with EtOAc (3 × 10 mL). Combined organic layers were dried over MgSO4, filtered,
and concentrated. The crude product was recrystallized from petroleum ether to yield a brown
solid.
4.7.1. N-[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methylphenyl]-2-iodoacetamide
(12a).
Yield: 78%; mp 98-99°C; 1H NMR (400 MHz, CDCl3) δ 9.04 (s, 1H), 8.33 (d, 3JH,H = 8.5 Hz, 1H),
7.31 (d, 3JH,H = 8.6 Hz, 1H), 3.84 (s, 2H), 3.58 (s, 3H), 2.36 (s, 3H); 13C NMR (101 MHz, CDCl3)
δ 164.8, 135.2, 134.7, 132.2, 130.1, 123.4, 122.6 (q, 1JC,F = 292 Hz), 114.6, 85.1 (p, 2JC,F = 28.6
Hz), 54.9, 21.2, 0.1; 19F NMR (376 MHz, CDCl3) δ -69.40 (s). Anal. Calcd for C13H12F6INO2 (%)
C, 34.31; H, 2.66; N, 3.08. Found: C, 34.03; H, 2.69; N, 2.78.
4.7.2. N-[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methoxyphenyl]-2-iodoacetamide
(12b).
Yield: 91%; mp 87-88°C; 1H NMR (400 MHz, CDCl3) δ 8.87 (s, 1H), 8.31 (d, 3JH,H = 8.9 Hz, 1H),
7.04 (d, J = 9.1 Hz, 1H), 7.03 (s, 1H), 3.84 (s, 2H), 3.81 (s, 3H), 3.57 (s, 3H); 13C NMR (101 MHz,
CDCl3) δ 164.7, 156.3, 130.5, 125.3, 122.5 (q, 1JC,F = 290. Hz), 116.6, 116.2, 115.9, 84.9 (p, 2JC,F
= 29 Hz), 55.7, 54.9, 0.1; 19F NMR (376 MHz, CDCl3) δ -69.46 (s). Anal. Calcd for C13H12F6INO3
(%) C, 33.14; H, 2.57; N, 2.97. Found: C, 33.10; H, 2.72; N, 3.18.
4.8. General procedure for synthesis of 13.
A mixture of 12 (4.4 mmol) and mesitylamine (9.3 mL, 65.9 mmol) was stirred at r.t. for 4 days.
After reaction completion, the mixture was treated with a 10% solution of NaHCO3 (60 mL) and
extracted with EtOAc (3×30 mL). Combined organic layers were washed with brine and water and
then dried over MgSO4 and concentrated under reduced pressure. The excess of MesNH2 was
removed at 70°C/0.05 mmHg. The residual solid was recrystallized from petroleum ether to yield
the corresponding aminoacetamide 7 as a white solid.

4.8.1. N-[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methylphenyl]-2-(mesitylamino)-
acetamide (13a).
Yield: 85%; mp 160-161°C; 1H NMR (400 MHz, acetone-d6) δ 10.12 (s, 1H), 8.58 (d, 3JH,H = 8.6
Hz, 1H), 7.40 (d, 3JH,H = 8.6 Hz, 1H), 7.33 (s, 1H), 6.82 (s, 2H), 4.25 (t, 3JH,H = 8.0 Hz, 1H), 3.74
(d, 3JH,H = 8.1 Hz, 2H), 3.59 (s, 3H), 2.38 (s, 3H), 2.30 (s, 6H), 2.19 (s, 3H); 13C NMR (101 MHz,
acetone-d6) δ 170.3, 143.6, 137.0, 134.5, 132.8, 132.5, 130.5, 130.4, 124.3, 123.6 (d, 1JC,F = 291
Hz), 114.9, 85.9 (p, 2JC,F = 28 Hz), 55.4, 53.8, 20.9, 20.6, 18.4; 19F NMR (376 MHz, acetone-d6)
δ -69.99 (s). Anal. Calcd for C22H24F6N2O2 (%) C, 57.14; H, 5.23; N, 6.06. Found: C, 57.17; H,
5.23; N, 5.71.
4.8.2. N-[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methoxyphenyl]-2-(mesitylamino)-
acetamide (13b).
Yield: 91%; mp 137-138°C; 1H NMR (400 MHz, acetone-d6) δ 9.93 (s, 1H), 8.53 (d, 3JH,H = 9.2
Hz, 1H), 7.21 (dd, J = 9.2, 2.8 Hz, 1H), 7.02 (s, 1H), 6.82 (s, 2H), 4.24 (t, 3JH,H = 7.8 Hz, 1H), 3.85
(s, 3H), 3.73 (d, 3JH,H = 7.9 Hz, 2H), 3.59 (s, 3H), 2.30 (s, 6H), 2.19 (s, 3H); 13C NMR (101 MHz,
1
acetone-d6) δ 170.1, 156.7, 143.7, 132.5, 132.2, 130.5, 130.4, 126.5, 123.5 (q, JC,F = 292 Hz),
116.8, 116.7, 116.3, 86.5–85.0 (m), 56.0, 55.5, 53.7, 20.6, 18.4; 19F NMR (376 MHz, acetone-d6)
δ -70.06 (s). Anal. Calcd for C22H24F6N2O3 (%) C, 55.23; H, 5.06; N, 5.86. Found: C, 55.42; H,
5.03; N, 5.96.
4.9. General procedure for synthesis of 14.
Aminoacetamide 13 (3.46 mmol) was dissolved in anhydrous toluene (30 mL), and BH3·SMe2
(15.6 mL of 1 M solution in THF, 15.6 mmol) was added dropwise under an argon atmosphere at
r.t. The resulting mixture was stirred at 90°C for 3 h. After cooling to r.t., MeOH was slowly added
until ceasing of gas evolution. Then, a 10% solution (60 mL) of HCl was added and resulting
mixture was extracted with EtOAc (2×20 mL). The aqueous layer was separated, treated with
NaHCO3, and extracted with EtOAc (2×20 mL). Combined organic layers were washed with a
saturated solution of NaHCO3, dried over MgSO4, and concentrated under reduced pressure. The
crude product was recrystallized from petroleum ether to yield a beige solid.
4.9.1. N1-[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methylphenyl]-N2-mesitylethane-
1,2-diamine (14a).
Yield: 90%; mp 53-54°C; 1H NMR (400 MHz, CDCl3) δ 7.13 (d, 3JH,H = 8.9 Hz, 1H), 7.11 (s, 1H),
6.86 (s, 2H), 6.72 (d, 3JH,H = 8.4 Hz, 1H), 5.70 (br.s, 1H), 3.54 (s, 3H), 3.46-3.39 (m, 2H), 3.20 (t,
3JH,H = 5.9 Hz, 2H), 2.30 (s, 6H), 2.27 (s, 3H), 2.25 (s, 3H); 13C NMR (101 MHz, CDCl3) δ 146.2,
132.2, 130.8, 130.7, 129.7, 125.6, 123.0 (q, 1JC,F = 293 Hz), 112.8, 108.7, 85.7 (p, 1JC,F = 28.3 Hz),
19
54.6, 48.1, 44.7, 20.7, 20.6, 18.2; F NMR (376 MHz, CDCl3) δ -69.46 (s). Anal. Calcd for
C22H26F6N2O (%) C, 58.92; H, 5.84; N, 6.25. Found: C, 58.81; H, 5.87; N, 5.96.

4.9.2.
N1-[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methoxyphenyl]-N2-
mesitylethane-1,2-diamine (14b).
Yield: 72%; mp 56-57°C; 1H NMR (400 MHz, CDCl3) δ 6.97 (d, 3JH,H = 8.9 Hz, 1H), 6.95 (s, 1H),
6.86 (s, 2H), 6.76 (d, 3JH,H = 8.8 Hz, 1H), 5.54 (s, 1H), 3.77 (s, 3H), 3.56 (s, 3H), 3.37 (dd, 3JH,H
=
10.9, 5.3 Hz, 2H), 3.19 (t, 3JH,H = 5.8 Hz, 2H), 2.93 (br.s, 1H), 2.29 (s, 6H), 2.26 (s, 3H); 13C NMR
1
(101 MHz, CDCl3) δ 150.8, 143.1, 142.9, 132.3, 130.7, 129.7, 122.9 (q, JC,F = 292 Hz), 117.5,
116.5, 113.9, 109.6, 85.6 (p, 2JC,F = 28 Hz), 56.0, 54.8, 48.1, 45.5, 20.7, 18.2; 19F NMR (376 MHz,
CDCl3) δ -69.50 (s). Anal. Calcd for C22H26F6N2O2 (%) C, 56.89; H, 5.64; N, 6.03. Found: C,
57.08; H, 5.65; N, 6.15.
4.10. General procedure for synthesis of 15.
Acetic formic anhydride (360 µL, 4.13 mmol) was added dropwise to the solution of 14 (2.06
mmol) in CH2Cl2 (13 mL). After homogenization, the reaction mixture was allowed to stir for 30
min at r.t. Then, 40 mL of water was added and the mixture was extracted with CH2Cl2 (2×30 mL).
Combined organic layers were washed with a saturated solution of NaHCO3 and water, dried over
MgSO4, filtered, and concentrated under reduced pressure. The crude product was purified by
column chromatography using EtOAc/petroleum ether (1:4) as eluent to yield colorless oil.
4.10.1. N-(2-{[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methylphenyl]amino}ethyl)-
N-mesitylformamide (15a).
Yield: 98%; mp 101-102°C; mixture of two rotamers 85:15, signals of major product are given: 1H
NMR (400 MHz, CDCl3) δ 8.06 (s, 1H), 7.13 (d, 3JH,H = 8.5 Hz, 1H), 7.10 (s, 1H), 6.97 (s, 2H),
6.75 (d, 3JH,H = 8.5 Hz, 1H), 5.80 (br.s, 1H), 3.81 (t, 3JH,H = 7.0 Hz, 2H), 3.52 (s, 3H), 3.37 (t, 3JH,H
= 7.0 Hz, 2H), 2.32 (s, 3H), 2.25 (s, 3H), 2.21 (s, 6H); 13C NMR (75 MHz, CDCl3) δ 164.2, 145.3,
138.7, 136.6, 136.0, 132.4, 130.6, 129.9, 126.2, 123.0 (q, 1JC,F = 292 Hz), 113.1, 109.3, 86.5–84.7
(m), 54.7, 45.7, 42.6, 21.0, 20.6, 18.3; 19F NMR (376 MHz, CDCl3) δ -69.55 (s). Anal. Calcd for
C23H26F6N2O2 (%) C, 57.98; H, 5.50; N, 5.88. Found: C, 57.69; H, 5.63; N, 6.04.
4.10.2. N-(2-{[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methoxyphenyl]amino}ethyl)-
N-mesitylformamide (15b).
Yield: 99%; mp 115-116°C; mixture of two rotamers 90:10, signals of major product are given: 1H
NMR (400 MHz, CDCl3) δ 8.06 (s, 1H), 6.97 (s, 2H), 6.95 (d, 3JH,H = 9.2 Hz, 1H), 6.91 (s, 1H),
6.81 (d, 3JH,H = 9.0 Hz, 1H), 5.84 (br.s, 1H), 3.80 (t, 3JH,H = 7.0 Hz, 2H), 3.74 (s, 3H), 3.52 (s, 3H),
3.36 (t, 3JH,H = 7.0 Hz, 2H), 2.31 (s, 3H), 2.21 (s, 6H); 13C NMR (75 MHz, CDCl3) δ 164.2, 151.2,
1
141.8, 138.7, 136.6, 136.0, 129.9, 122.9 (q, JC,F = 293 Hz), 117.6, 116.6, 114.3, 110.2, 85.5 (p,
2JC,F = 28 Hz), 56.0, 54.8, 45.8, 43.0, 21.0, 18.3; 19F NMR (376 MHz, CDCl3) δ -69.61 (s). Anal.
Calcd for C23H26F6N2O3 (%) C, 56.10; H, 5.32; N, 5.69. Found: C, 56.11; H, 5.55; N, 5.91.
4.11. General procedure for synthesis of 16.

Triflic acid (180 µL, 2.0 mmol) was added to the solution of 15 (2.0 mmol) in toluene (50 mL),
and the mixture was stirred at r.t. for 15 min. Then, triflic anhydride (340 µL, 2.0 mmol) was
added, and the reaction mixture was heated at 65°C for 1.5 h. DIPEA (1.04 mL, 6.0 mmol) was
added, and the reaction mixture was heated at 80°C for another 1.5 h. After cooling to r.t., 50 mL
of water was added and the mixture was extracted with CH2Cl2 (3×30 mL). The combined organic
layers were dried using MgSO4, filtered, and concentrated under reduced pressure. The crude
product was recrystallized from petroleum ether to yield a beige solid.
4.11.1.
1-[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methylphenyl]-3-mesityl-4,5-
dihydro-1H-imidazol-3-ium triflate (16a).
Yield: 85%; mp 167-169°C; 1H NMR (400 MHz, CDCl3) δ 8.08 (s, 1H), 7.74 (d, 3JH,H = 8.1 Hz,
1H), 7.53 (s, 1H), 7.46 (d, 3JH,H = 8.0 Hz, 1H), 6.95 (s, 2H), 4.64 (t, 3JH,H = 10.6 Hz, 2H), 4.40 (t,
13
3JH,H = 10.6 Hz, 2H), 3.61 (s, 3H), 2.44 (s, 3H), 2.34 (s, 6H), 2.29 (s, 3H); C NMR (101 MHz,
CDCl3) δ 159.7, 141.9, 141.0, 135.1, 133.9, 132.3, 132.0, 131.6, 130.2, 130.1, 125.0, 122.3 (q,
1
19
1JC,F = 290 Hz), 120.7 (q, JC,F = 320 Hz), 84.2–82.8 (m), 55.7, 55.1, 51.8, 21.6, 21.1, 17.7; F
NMR (376 MHz, CDCl3) δ -69.24 (s, 6F), -78.59 (s, 3F). Anal. Calcd for C24H25F9N2O4S (%) C,
47.37; H, 4.14; N, 4.60. Found: C, 47.61; H, 4.14; N, 4.58.
4.11.2.
1-[2-(1,1,1,3,3,3-Hexafluoro-2-methoxypropan-2-yl)-4-methoxyphenyl]-3-mesityl-4,5-
dihydro-1H-imidazol-3-ium triflate (16b).
Yield: 83%; mp 171-173°C; 1H NMR (400 MHz, CDCl3) δ 8.04 (s, 1H), 7.85 (d, 3JH,H = 8.7 Hz,
1H), 7.25 (s, 1H), 7.15 (dd, JH,H = 8.7, 2.6 Hz, 1H), 6.95 (s, 2H), 4.61 (t, 3JH,H = 10.5 Hz, 2H), 4.39
(t, 3JH,H = 10.4 Hz, 2H), 3.84 (s, 3H), 3.61 (s, 3H), 2.34 (s, 6H), 2.29 (s, 3H); 13C NMR (101 MHz,
CDCl3) δ 161.0, 159.9, 141.0, 135.1, 133.9, 130.2, 130.1, 126.9, 126.7, 122.3 (q, 1JC,F = 291 Hz),
120.7 (q, 1JC,F = 320 Hz), 118.3, 116.8, 84.2-82.6 (m), 56.0, 55.8, 55.1, 51.8, 21.1, 17.7; 19F NMR
(376 MHz, CDCl3) δ -69.27 (s, 6F), -78.55 (s, 3F). Anal. Calcd for C24H25F9N2O5S (%) C, 46.16;
H, 4.03; N, 4.49. Found: C, 46.21; H, 4.06; N, 4.51.
4.12. General procedure for synthesis of Grubbs-type catalysts 3 and 4.
In a flame-dried Schlenk flask, imidazolinium salt 16 (0.49 mmol) was mixed with 20 mL of
anhydrous toluene. The resulting mixture was cooled to 0°C and degassed three times, and then
KHMDS (1 mL of 0.5 M solution in toluene, 0.50 mmol) was added to the mixture under an argon
atmosphere. The reaction mixture was stirred for 30 min at r.t.; then Grubbs’ catalyst G-I (0.33 g,
0.40 mmol) was added and mixture was stirred for 2 h. During this time, the reaction mixture
changed color from violet to red-brown. Once complete (TLC-control), solvents were removed
from the reaction mixture under reduced pressure, and the resulting substance was purified by
column chromatography in a gradient manner using EtOAc/petroleum ether (1:8−1:3) as eluent

under an argon atmosphere. The resulting solid was recrystallized from MeOH to yield 11 as a
brown solid.
4.12.1.
Benzylidene(dichloro){1-[2-(1,1,1,3,3,3-hexafluoro-2-methoxypropan-2-yl)-4-
methylphenyl]-3-mesityl-4,5-dihydroimidazol-2-ylidene}(triphenylphosphine)ruthenium(II) (3).
1
Yield: 46%; mixture of two rotamers 4:1 at 60°C, signals of major product are given: H NMR
(400 MHz, toluene-d8, 60°C) δ 19.62 (s, 1H, CHAr), 9.47 (d, JH,H = 7.9 Hz, 1H, ArH), 8.25 (s, 1H,
ArH), 7.74 (s, 1H, ArH), 7.35 (d, JH,H = 7.5 Hz, 1H, ArH), 7.20-7.10 (m, 2H, ArH), 6.94-6.72 (m,
2H, ArH), 6.34 (br.s, 1H, ArH), 6.01 (m, 1H, ArH), 4.43 (s, 1H, CH2CH2), 4.12 (s, 3H,
C(CF3)2OCH3), 3.78 (s, 1H, CH2CH2), 3.39 (s, 1H, CH2CH2), 3.24 (s, 1H, CH2CH2), 2.48 (s, ,
13
CH3), 2.74-0.92 (m, 42H, PCy3, CH3); C NMR (126 MHz, toluene-d8, 60°C) δ 298.2, 223.4,
152.4, 139.6, 142.2, 138.9, 138.7, 137.0, 136.7, 135.4, 131.9 (br.s), 130.6, 130.4, 129.7, 129.5,
128.3, 123.6 (q, 1JC,F = 289 Hz), 123.4 (q, 1JC,F = 290 Hz), 117.6, 117.3, 85.6-84.1 (m), 58.5, 54.9,
52.2, 29.8, 29.5, 29.4, 28.1-28.0 (m), 26.8, 21.0, 19.3, 19.0; 19F NMR (376 MHz, toluene-d8, 60°C)
δ -65.29 (br.s, 3F), -71.15 (br.s, 3F); 31P NMR (202 MHz, toluene-d8, 60°C) δ 24.2 (s). Anal. Calcd
for C48H63Cl2F6N2OPRu (%) C, 57.60; H, 6.34; N, 2.80. Found: C, 57.39; H, 6.47; N, 2.84.
4.12.2.
Benzylidene(dichloro){1-[2-(1,1,1,3,3,3-hexafluoro-2-methoxypropan-2-yl)-4-
methoxyphenyl]-3-mesityl-4,5-dihydroimidazol-2-ylidene}(triphenylphosphine)ruthenium(II) (4).
1
Yield: 48%; mixture of two rotamers 4:1 at 50°C, signals of major product are given: H NMR
(400 MHz, toluene-d8, 50°C) δ 19.59 (s, 1H, CHAr), 9.62 (br.s, 1H, ArH), 9.47 (br.s, 1H, ArH),
7.61 (s, 1H, ArH), 7.21 (t, JH,H = 7.3 Hz, 1H, ArH), 7.12 (dd, JH,H = 8.8, 2.6 Hz, 1H, ArH), 7.08-
6.86 (m, 4H, ArH), 6.54 (br.s, 1H, ArH), 4.39 (br.s, 1H, CH2CH2), 4.10 (s, 3H, C(CF3)2OCH3),
3.76 (br.s, 1H, CH2CH2), 3.43 (s, 3H, ArOCH3), 3.38 (br.s, 1H, CH2CH2), 3.25 (s, 1H, CH2CH2),
13
2.77-0.81 (m, 42H, PCy3, CH3); C NMR (126 MHz, toluene-d8, 50°C) δ 298.2, 223.3, 159.3,
152.4, 139.8, 138.9, 138.7, 137.0, 136.7, 135.4, 132.0 (br.s), 130.6, 130.4, 129.7, 129.5, 128.3,
1
1
123.63 (q, JC,F = 284 Hz), 123.58 (q, JC,F = 288 Hz), 117.6, 117.3, 85.4-84.1 (m), 58.5, 56.3,
54.9, 52.2, 29.8, 29.4, 28.2-28.1 (m), 26.8, 21.0, 19.3, 18.9; 19F NMR (471 MHz, toluene-d8, 50°C)
31
δ -65.50 (br.s, 3F), -71.13 (br.s,, 3F); P NMR (202 MHz, toluene-d8, 50°C) δ 24.6 (s). Anal.
Calcd for C48H63Cl2F6N2O2PRu (%) C, 56.69; H, 6.24; N, 2.75. Found: C, 56.68; H, 6.42; N, 2.77.
4.13. General procedure for synthesis of Hoveyda-Grubbs-type catalysts 5 and 6.
In a flame-dried Schlenk flask, imidazolinium salt 16 (0.40 mmol) was mixed with 9 mL of
anhydrous toluene. The resulting mixture was cooled to 0°C and degassed three times; then
KHMDS (840 µL of 0.5 M solution in toluene, 0.42 mmol) was added to the mixture under an
argon atmosphere. The reaction mixture was stirred for 30 min at r.t.; then Hoveyda-Grubbs
catalyst first generation H-I (0.20 g, 0.30 mmol) was added and mixture was stirred for 40 min at
80°C. During this time, the reaction mixture changed color from brown to dark green. Once

complete, solvents were removed from the reaction mixture under reduced pressure, and the
resulting substance was purified by column chromatography using EtOAc/petroleum ether (1:3)
as eluent to yield. Hoveyda-type catalyst as a green solid. Suitable for X-ray crystals of 5 and 6
were grown by slow diffusion of hexane vapors in CH2Cl2 solution.
4.13.1.
Dichloro{1-[2-(1,1,1,3,3,3-hexafluoro-2-methoxypropan-2-yl)-4-methylphenyl]-3-
mesityl-4,5-dihydroimidazol-2-ylidene}(2-isopropoxybenzylidene)ruthenium(II) (5).
Yield: 74%; 1H NMR (500 MHz, toluene-d8, 80°C) δ 16.91 (s, 1H, CHAr), 9.14 (br.s, 1H, ArH),
7.78 (s, 1H, ArH), 7.21 (br.s, 1H, ArH), 7.10 (m, 1H, ArH), 6.94 (dd, JH,H = 7.5, 1.1 Hz, 1H, ArH),
3
3
6.89 (s, 1H, ArH), 6.82 (s, 1H, ArH), 6.59 (t, JH,H = 7.4 Hz, 1H, ArH), 6.43 (d, JH,H = 8.3 Hz,
3
1H, ArH), 4.56 (hept, JH,H = 6.3 Hz, 1H, OiPr, CH), 4.51 (m, 1H, H2I CH2CH2), 3.86 (s, 3H,
C(CF3)2OCH3), 3.69 (q, JH,H = 9.9 Hz, 1H, H2I CH2CH2), 3.48 (q, JH,H = 9.9 Hz, 1H, H2I CH2CH2),
3.42 (q, JH,H = 9.3 Hz, 1H, H2I CH2CH2), 2.51 (s, 3H, CH3), 2.37 (s, 3H, CH3), 2.21 (s, 3H, CH3),
2.16 (s, 3H, CH3), 1.39 (s, 3H, OiPr CH3), 1.31 (d, 3JH,H = 6.1 Hz, 3H, OiPr CH3); 13C NMR (126
MHz, toluene-d8, 80°C) δ 294.0, 216.8, 153.3, 145.6, 142.4, 138.8, 138.7, 137.8, 134.1 (br.s),
130.4, 130.1, 130.0, 129.5, 123.8 (q, 2JC,F = 289 Hz), 123.4 (q, 2JC,F = 289 Hz), 122.4, 122.3, 113.4,
85.4 (hept, 1JC,F = 27 Hz), 75.1, 58.0, 54.6 (br.s), 53.1 (br.s), 22.4, 22.2, 22.1, 21.9; 19F NMR (471
MHz, toluene-d8, 60°C) δ -65.6 (br.s, 3F), -71.7 (br.s, 3F). Anal. Calcd for C33H36Cl2F6N2O2Ru
(%) C, 50.90; H, 4.66; N, 3.60. Found: C, 50.78; H, 4.89; N, 3.42. CCDC 1543696 contains the
supplementary crystallographic data for this paper. These data can be obtained free of charge from
The Cambridge Crystallographic Data Centre via http://www.ccdc.cam.ac.uk.
4.13.2.
Dichloro{1-[2-(1,1,1,3,3,3-hexafluoro-2-methoxypropan-2-yl)-4-methoxyphenyl]-3-
mesityl-4,5-dihydroimidazol-2-ylidene}(2-isopropoxybenzylidene)ruthenium(II) (6).
Yield: 71%; 1H NMR (500 MHz, toluene-d8, 80°C) δ 16.92 (br.s, 1H, CHAr), 9.13 (br.s, 1H, ArH),
7.61 (s, 1H, ArH), 7.10 (m, 1H, ArH), 6.98 (dd, JH,H = 1.5, 7.4 Hz, 1H, ArH), 6.92 (br.s, 1H, ArH),
3
3
6.89 (s, 1H, ArH), 6.83 (s, 1H, ArH), 6.58 (t, JH,H = 7.4 Hz, 1H), 6.42 (d, JH,H = 8.3 Hz, 1H,
3
ArH), 4.56 (hept, JH,H = 6.1 Hz, 1H, OiPr CH), 4.48 (td, JH,H = 9.6, 3.2 Hz, 1H, H2I CH2CH2),
3.85 (s, 3H, C(CF3)2OCH3), 3.70 (m, 1H, H2I CH2CH2), 3.48 (m, 1H, H2I CH2CH2), 3.40 (m, 1H,
H2I CH2CH2), 3.38 (s, 3H, ArOCH3), 2.52 (s, 3H, CH3), 2.39 (s, 3H, CH3), 2.22 (s, 3H, CH3), 1.32
(d, 3JH,H = 6.1 Hz, 6H, OiPr CH3); 13C NMR (126 MHz, toluene-d8, 80°C) δ 294.0, 216.8, 159.7,
1
153.3, 145.7, 138.8, 138.7, 137.8, 134.7 (br.s), 130.4, 130.1, 129.5, 129.1, 123.8 (q, JC,F = 293
1
Hz), 123.4 (q, 1JC,F = 289 Hz), 122.4, 122.3, 113.4, 85.3 (hept, JC,F = 27 Hz), 75.1, 58.0, 55.4,
19
54.8 (br.s), 53.0 (br.s), 22.3, 22.2, 22.1, 21.9; F NMR (282 MHz, toluene-d8, 60°C) δ -65.89, -
70.73. Anal. Calcd for C33H36Cl2F6N2O3Ru (%) C, 49.88; H, 4.57; N, 3.53. Found: C, 49.91; H,
4.52; N, 3.27. CCDC 1543695 contains the supplementary crystallographic data for this paper.

These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via
http://www.ccdc.cam.ac.uk.
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Graphical abstract:
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Time [min.]
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<InlineImage1>
Figure 4. RCM of DEDAM with catalysts 3, 4 as compared to 1, G-II and H-II
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Time [min.]
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6
<InlineImage2>

Figure 5. RCM of DEDAM with catalysts 5, 6 as compared to 2, G-II and H-II
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Time [min.]
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<InlineImage3>
Figure 6. CM of allylbenzene with 1,3-diacetoxybut-2-ene with catalysts 3, 4
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Time [min.]
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<InlineImage4>
Figure 7. CM of allylbenzene with 1,3-diacetoxybut-2-ene with catalysts 5, 6