Nano-dispersed platinum(0) in organically modified silicate matrices as sustainable catalysts for a regioselective hydrosilylation of alkenes and alkynes

Article abstract of DOI:10.1039/c8nj01889h

Nano-dispersed platinum(0) particles stabilized in a range of organically modified silicate (ORMOSIL) matrices are investigated as sustainable catalysts for the hydrosilylation of alkenes and alkynes. In this study, five different siloxane matrices including triethoxysilane (HTEOS), methyltriethoxysilane (MTES), ethyltriethoxysilane (ETES), triethoxyvinylsilane (TEVS) and propyltriethoxysilane (PTES) are investigated, and the distribution of the metal particles in these materials analyzed by transition electron microscopy (TEM). The particles appeared to be generally of a small size, with a diameter of ca. 2-5 nm in each of these catalysts, however the distribution is not equally uniform from one matrix to the other. HTEOS, MTES and ETES that respectively carry a hydrogen, a methyl and an ethyl group on the triethoxysilane moiety, displayed a more uniform distribution, while particles appeared to be more scattered in the remaining matrices. Catalysts with a uniform particles distribution produced higher and consistent yields, while those with poor particles distribution produced lower and almost random yields, suggesting that the uniformity in particle distribution, and by extension the nature of the siloxane matrix, are important for the catalytic properties of these materials. The scope of the reaction was broadened to a range of olefins, with a goal of investigating the tolerability of the reaction toward a number of reactive functional groups, resulting in the preparation of 28 compounds. This catalytic system also enabled the hydrosilylation of a limited number of alkynes under the optimized reaction conditions.

Full text of DOI:10.1039/c8nj01889h

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Nano-dispersed platinum(0) in organically modified silicate matrices as sustainable
catalysts for a regioselective hydrosilylation of alkenes and alkynes
Brett J. Duke, Evan N. Akeroyd, Shreeja V. Bhatt, Chibueze I. Onyeagusi, Shreya V. Bhatt, Brandy R.
Adolph and Jean Fotie*
Nano-dispersed platinum(0) particles stabilized in a range of organically modified silicate (ORMOSIL)
matrices are investigated as sustainable catalysts for the hydrosilylation of alkenes and alkynes. In this
study, five different siloxane matrices including triethoxysilane (HTEOS), methyltriethoxysilane (MTES),
ethyltriethoxysilane (ETES), triethoxyvinylsilane (TEVS) and propyltriethoxysilane (PTES) are
investigated, and the distribution of the metal particles in these materials analyzed by transition
electron microscopy (TEM). The particles appeared to be generally of a small size, with a diameter of
ca 2 – 5 nm in each of these catalysts, however the distribution is not equally uniform from one matrix
to the other. HTEOS, MTES and ETES that respectively carry a hydrogen, a methyl and an ethyl group
on the triethoxysilane moiety, displayed a more uniform distribution, while particles appeared to be
more scattered in the remaining matrices. Catalysts with a uniform particles distribution produced
higher and consistent yields, while those with poor particles distribution produced lower and almost
random yields, suggesting that the uniformity in particle distribution, and by extension the nature of
the siloxane matrix, are important for the catalytic properties of these materials. The scope of the
reaction was broadened to a range of olefins, with a goal of investigating the tolerability of the reaction
toward a number of reactive functional groups, resulting in the preparation of 28 compounds. This
catalytic system also enabled the hydrosilylation of a limited number of alkynes under the optimized
reaction conditions.
_________________________________________________________________________________
Department of Chemistry and Physics, Southeastern Louisiana University
SLU 10878, Hammond, LA 70402-0878, United States.
*E-mail: jean.fotie@southeastern.edu
†Electronic supplementary informaꢀon (ESI) available (1H NMR, 13C NMR, HRMS (ESI/Q-TOF) and GC-MS)
1

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1. Introduction
Silicon is the second most abundant element in the Earth's crust (about 28% by mass) after oxygen,
and as such, it is only natural for silicon-based materials to be widely used in a large number of
consumer goods and commodity chemicals including polymers (adhesives, coatants, sealants, gels,
foams, aerosols, encapsulants and preservatives),1-5 semi-conductors,6-10 agrochemical and biomedical
agents.11-13 In recent years, chiral organosilanes have gradually established their importance in organic
synthesis,14-16 material science17-21 and medicinal chemistry,22, 23 as a result of the involvement of silane
intermediates in diverse chemical transformations including silicon-based cross-coupling reactions,24-
28 silanol hydrogen bond donor catalysis,29, 30 and as directing groups for C–H functionalization,31-37 to
name just a few. Furthermore, silasubstitution of bioactive molecules, also known as “silicon switch”,
has become a growing practice in medicinal chemistry, especially in the preparation of silicon-based
peptidomimetic analogues.22, 23, 38, 39 This trend has rejuvenated hydrosilylation reactions as a strategic
approach to access a large diversity of key silane intermediates.32, 40-43
Although a number of metal catalysts have been used to enable these reactions,32, 40-43 the constant
need for more selective, cleaner and sustainable transformations has inspired the development of
alternative hydrosilylation reactions. With the emergence of the continuous flow industrial processes,
which offer many advantages over traditional batch reactors, including a high surface-to-volume ratio,
better heat and mass transfer, and more control over the reaction conditions,44-46 there is a need for
the development of a new generation of catalysts compatible with these processes. The
heterogenization of homogeneous catalytic methods through the dispersion or encapsulation of
metallic nanoparticles in porous matrices is one of the approaches compatible with continuous flow
processes.45-50 This approach, in addition to offering a unique high specific surface area and large pore
volume, in conjunction with the tunability of pore size, also enables an easy separation of the product,
and the reusability of the catalyst.45-52 Because silica-based sol−gels are extremely porous materials
with high specific area, nano-dispersed and stabilized metallic catalysts in organically modified silicates
(ORMOSILs) have been investigated as potential catalysts for continuous flow processes.48, 49, 52
Ciriminna et al.,45 reported that Pt(0) dispersed in a methyltriethoxysilane matrix could catalyze the
hydrosilylation of a number of terminal alkenes. However, in this initial study, only a very limited
number of alkenes was investigated, triethoxysilane was the only silylating agent investigated, and all
the yields were determined by GC-MS. This study explores and compares the catalytic properties of
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nano-dispersed and stabilized Pt(0) in a series of sol-gel siloxane matrices on the hydrosilylation of a
wide range of olefins, using the Speier’s catalyst as a control. The scope of the reaction is expanded to
include the variation of substituents on a core aromatic system, with a goal of investigating the
tolerability of a number of functional groups by the reaction. Other silylating agents are investigated,
and a limited number of alkynes were also hydrosilylated under the optimal reaction conditions.
2. Results and discussion
The preparation of a highly dispersed metal and stabilized in the form of sol-gel using organically
53, 54
modified silicates is routine.45-47,
Pt@MTES was prepared by dispersing potassium
tetrachloroplatinate (K2PtCl4) in methyltriethoxysilane, then reduced it to Pt(0) with NaBH4 as
previously described.45 A quick optimization of the hydrosilylation reaction conditions using 1-
octadecene as a substrate was undertaken, as illustrated in Table 1.
No reaction was observed with 0.01% Pt in MTES at 100 oC for 6 h in toluene (entry 1), and only traces
of product were observed when 0.05% Pt in MTES was used (entry 2). Under the same conditions, the
yield of the reaction improved as the catalyst load increases, however when going from 1% Pt to 2%
(entries 4 and 5), the yield decreased substantially. A full conversion was achieved with 1.2 eqv of
triethoxysilane and 1 mol% Pt in toluene in 18 h at 100 oC (entry 7), but the yield did not improve when
o
o
o
the temperature was increased to 140 C (entry 8) or lowered to 60 C (entry 9). At 140 C, the
competitive hydrogenation of the alkene through a hydrogen-transfer reaction appeared to
accelerate. Furthermore, coordinating solvents such as THF, THF/H2O (1:1), H2O, CH3CN or isopropanol
failed to produced any product as indicated by GC-MS, and only dioxane was able to produce the
expected product, with a very poor yield (entry 14). As a result, the conditions in entry 7 were selected
for the exploration of the scope of the reaction.
With the optimal reaction conditions at hand, a comparative analysis between Pt@MTES and the
Speier’s catalyst (widely used for hydrosilylation in industrial settings as a homogeneous catalyst)32, 55,
56 was undertaken, and the obtained results are summarized in Figure 1. The reaction with Pt@MTES
o
was set up using the conditions in entry 7 (temperature 100 C), while the reaction with the Speier’s
catalyst (H2PtCl6.6H2O) was set up based on the original report by Speier et al.57, 58 (temperature 140
oC). Due to the low boiling point of the commercially available alkenes, which makes it difficult to
isolate and characterize the resulting hydrosilylated products, a number of terminal alkenes were
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quickly prepared either through a Williamson etherification reaction (for ethers)59-61 or by
esterification of the acyl chloride (for esters).
Table 1. Hydrosilylation of 1-octadecene with triethoxysilane using Pt@MTES as a catalyst
Entry Triethoxysilanea
(eqv)
Solvent
Pt@MTESb Time (h)
(Pt, mol%)
Temp
(oC)
Yieldc
(%)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
1
1
1
1
1
1
1.2
1.2
1.2
1.2
1.2
1.2
1.2
1.2
1.2
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
THF
0.01
0.05
0.5
1
2
1
1
1
1
1
6
6
6
6
100
100
100
100
100
100
100
60
140
reflux
reflux
reflux
reflux
100
N.Rd
traces
38
62
53
70
73e
54
66e
N.R
N.R
N.R
traces
34
6
18
18
18
18
18
18
18
18
18
18
THF/H2O (1:1)
H2O
CH3CN
Dioxane
Isopropanol
1
1
1
1
1
reflux
N.R
Each reaction was setup under nitrogen environment, using 1 mmol of 1-octadecene. aThe equivalence is related to the number of moles
of 1-octadecene. bThe percent mole is related to the number of moles of 1-octadecene. c The yield of the reaction was determined by
GC-MS using tridecane as an internal standard. N.R. = No Reaction. No 1-octadecene was present in the mixture at the end of the
reaction as indicated by GC-MS.
d
e
Under these conditions, the two catalysts apeared to behave amazingly in a very analogous manner,
producing similar yields for a number of starting materials. Both catalytic systems selectively produced
the anti-Markonikov product. The yields appeared to be higher for substrates with saturated carbon
chains than with those bearing an aromatic ring. Ether and ester functional groups were well tolerated
under these conditions, while the substrate bearing an amine functional group produced a very poor
yield, although Pt@MTES generated a better yield than the Speier’s catalyst in this latter case
(compound 6). Unfortunately, both catalytic systems systematically failed to produce the expected
product when an alkene with an internal double bond (trans-stibene or cyclooctene) was used as a
substrate.
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Figure 1: Comparative analysis between the Speier’s and Pt@MTES (*these are isolated yields from gram-scale reactions)
5

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Since substrates bearing a benzene ring appeared to produce a much lower yield than their saturated
counterparts, it became interesting to investigate whether substituents on the ring will have any
effect on the reaction’s outcome (Scheme 1). The collected results are summarized in Table 2. The
reaction produced comparable and quantitative yields under both the Pt@MTES and the Speier’s
catalytic systems. The substituents on the aromatic ring did not appear to be affecting the outcome
of the reaction in any meaningful way, which is not surprising given how far away the ring is to the
site of the reaction.
Scheme 1: Hydrosilylation of substituted allyloxybenzenes using Pt@MTES and Speier’s catalytic
systems.
Table 2: Percent yields obtained from the hydrosilylation of substituted allyloxybenzenes.
Compounds
12a
R1
H
H
Cl
H
H
H
H
H
H
H
H
R2
R3
H
% Yield for Speier’sa
% Yield for Pt@MTES a
H
H
62
59
65
56
46
57
54
58
54
62
39
55
62
57
58
58
60
63
64
56
61
58
12b
Cl
12c
H
H
12d
H
Br
12e
Cl
Cl
12f
H
Me
i-Pr
H
12g
H
12h
OMe
Me
CO2Me
H
12i
Me
H
12j
12k
CO2Me
aIsolated yields from gram-scale reactions
The collected data unambiguously showed that Pt@MTES was equally effective as the Speier’s
catalyst in the hydrosilylation of alkenes, making the heterogenization of homogeneous catalytic
systems a viable approach for industrial application. Considering that sustainability (relationships

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between manufacturing system and ecosystems, and economic viability) and process intensification
(running reactions under continuous conditions that speed up conversion rates, while maintaining
selectivity) are becoming more and more relevant in the chemical industry, this catalytic system might
even be preferable if well integrated into a continue flow process.
In order to investigate whether the lipophilic carbon chain on the silicate matrix can impact the
catalytic effect, Pt(0) was nano-dispersed in a range of matrices, including triethoxysilane (HTEOS),
ethyltriethoxysilane (ETES), triethoxyvinylsilane (TEVS) and propyltriethoxysilane (PTES). The catalytic
effect of the resulting materials on the hydrosilylation of alkenes was compared to that of Pt@MTES,
and the obtained results are summarized in Table 3. The percent yields obtained with Pt@HTEOS and
Pt@ETES were consistent and similar to those obtained with Pt@MTES, while the percent yields were
more inconsistent and scattered with Pt@PTES and Pt@TEVS.
Table 3: Comparative analysis of the catalytic effects of Pt@MTES, Pt@HTEOS, Pt@ETES, Pt@PTES
and Pt@TEVS.
Compounds
Pt@MTES
Pt@HTEOS
Pt@ETES
Pt@PTES
Pt@TEVS
(% yield)
61
(% yield)
64
(% yield)
42
(% yield)
26
(% yield)
40.
50
4
5
69
68
42
33
9
54
64
63
38
46
12a
12b
12e
12h
12i
55
48
43
38
46
62
55
57
39
38
58
58
51
58
44
64
53
54
48
32
56
44
47
40
17
*
yields are isolated from gram-scale reactions
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To rationalize the observed trend, the particle distribution in Pt@MTES, Pt@HTEOS, Pt@ETES,
Pt@PTES and Pt@TEVS were analyzed with a Transition Electron Microscope (TEM). The particles
appeared to be generally of a small size in each of the catalysts, with a diameter mostly between 2 –
5 nm (Figure 2). However, the distribution was not equally uniform from one matrix to the other. In
the catalysts that produced more consistent percent yields during the comparative analysis, namely
Pt@HTEOS, Pt@MTES and Pt@ETES (Figure 2, (a), (b) and (c) respectively), the distribution was more
uniform, while particles appeared to be more scattered in Pt@TEVS and Pt@PTES (Figure 2, (d) and
(e), respectively), the catalysts that produced inconsistent percent yields.
(a)
(b1)
(b2)
(c)
(d)
(e)
Figure 2: TEM pictures of (a) Pt@HTEOS, (b1 and b2) Pt@MTES, (c) Pt@ETES, (d) Pt@TEVS and (e)
Pt@PTES
This was not surprising since HTEOS, MTES and ETES formed a gel quite easily during the preparation
of these catalysts, while PTES and TEVS slowly produced rubber-like films, resulting in the poor
particles distribution observed by TEM. These observations suggest that the uniformity in particle
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distribution is responsible for the catalytic trend observed. It is not sure whether (or how) the
lipophilic carbon chain on the silicate matrix impact the catalytic effect of these materials, but it is
obvious that the silane derivative used to generate a given catalyst and the nature of the resulting
matrix has a significant impact on the particle size as well as on the uniformity of their distribution.
As a result, all these parameters appeared to be interconnected, and each of them has an effect on
the catalytic properties of the resulting material.
In order to determine whether other silylating agents could be used under this catalytic system,
phenylsilane, diethylsilane, triethylsilane, methyldiethoxysilane and diphenylsilane were
investigated, using Pt@HTEOS as the catalyst under entry 7’s reaction conditions. Phenylsilane and
diphenylsilane failed to produce the expected product probably because of steric hindrance
generated by the benzene ring(s), and the starting materials were collected every time. However, the
remaining hydrogensilanes produced the expected product in quantitative yields, as illustrated with
compounds 13 – 16.
To investigate whether alkynes could be hydrosylilated under these condition, four symmetrical
alkynes, namely diphenylacetylene, hex-3-yne, 1,4-bis(benzyloxy)but-2-yne and 1,4-bis(4-
methylbenzyloxy)but-2-yne, together with two terminal alkynes namely (prop-2-ynyloxy)benzene and
1-chloro-4-(prop-2-ynyloxy)benzene were individually reacted with triethoxysilane under the
conditions shown in entry 7, Table 1. All these starting materials were efficiently hydrosilylated, with
diphenylacetylene
and
hex-3-yne producing
inseparable
mixtures
of
(E/Z)-(1,2-
diphenylvinyl)triethoxysilane (17, 70%) and (E/Z)-triethoxy(hex-3-en-3-yl)silane (18, 58%) in
quantitative yields, respectively (Scheme 2). The GC-MS analysis (see supplemental data) of these
mixtures showed that they contain an excess of the Z isomer (the compound with a trans double
bond), with roughly 70% (Z) versus 30% (E) for (1,2-diphenylvinyl)triethoxysilane, and 75% (Z) versus
25% (E) for triethoxy(hex-3-en-3-yl)silane, respectively. The low boiling point for triethoxy(hex-3-en-
3-yl)silane might be responsible for the low yield obtained for this compound, as some of the product
was lost during the evaporation of the solvent.
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Scheme 2: Hydrosilylation of diphenylacetylene and hex-3-yne.
Interestingly, the two other symmetrical alkynes, namely, 1,4-bis(benzyloxy)but-2-yne and 1,4-bis(4-
methylbenzyloxy)but-2-yne produced almost exclusively the Z isomer of (1,4-bis(benzyloxy)but-2-en-
2-yl)triethoxysilane (19) and (1,4-bis(4-methylbenzyloxy)but-2-en-2-yl)triethoxysilane (20),
respectively, in quantitative yields. Furthermore, the two terminal alkynes produced almost
exclusively the anti-Markonikov E isomers (the compounds with a trans double bond) of the
hydrosilylated product (21 and 22).
The reusability of the catalyst was study with Pt@MTES, using allyl glycidyl ether as a substrate in the
preparation of 5, under the optimized conditions (entry 7, Table 1). The catalyst was recovered from
the reaction mixture by centrifugation followed by the removal of the supernatant by decantation at
the end of each cycle. The catalyst was then sonicated for about 45 minutes in THF, washed and air-
dried before the next run. It should be noted that the amount of substrate was adjusted for each run
in order to make up for the catalyst loss during each recovery. The obtained results (Figure 3) show
about a 10% loss in yield from one cycle to another, up to four runs before the amount of the catalyst
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recovered become too small to be used for another cycle. The decrease in yield appeared to be
primarily associated with the pores blockage in the sol-gel material, rather than to the loss in catalytic
activity. In fact, the reduction in yield appeared to be more dramatic when the catalyst is not sonicated
between cycles. It is noteworthy to mention that a previous study with Pt@MTES under similar
conditions have shown only very low levels of Pt (4-6 ppm) leaching.45 The authors of that study also
found that the higher level of leaching was associated with molecules bearing functional groups
capable to coordinate the Pt nanoparticles.45 Even so, it should be noted that this level of leaching is
marginal when compared to the level observed with homogeneous Pt-catalyzed hydrosilylation
applications.62, 63
69
70
57
60
44
50
40
30
20
10
0
32
1
2
3
4
Number of cycles
Figure 3: Study of the reusability of Pt@MTES using allyl glycidyl ether as a substrate in the
preparation of 5.
3. Conclusion
Nano-dispersed platinum(0) particles stabilized in five organically modified silicate (ORMOSIL)
matrices have been investigated for their catalytic effects on the hydrosilylation of alkenes and
alkynes. The Transition Electron Microscopy (TEM) analysis of these material revealed that particles
were mostly of a small size. However, the distribution was not equally uniform in each of the matrices.
Pt@MTES, Pt@HTEOS and Pt@ETES that displayed a more uniform particle distribution, also
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produced higher and consistent yields. However, catalysts with uneven particles distribution resulting
from the obtained poor gel-material produced low and inconsistent results. These observations
suggest that the uniformity in particle distribution, which is directly linked to the quality of the xerogel
obtained, is very important for the catalytic properties of these materials. Moreover, while internal
alkenes failed to produce the expected product during this study, the reaction proceeded well with
internal and terminal alkynes, producing a mixture of cis/trans isomers for some symmetrical alkynes,
and an anti-Markovnikov selectivity for terminal alkenes and alkynes. Considering that sustainability
and process intensification are becoming more and more relevant in the chemical industry, the
catalytic system investigated in this report appeared to be equally robust and could be more
sustainable than the current industrial practices, if well integrated into a continue flow process.
4. Experimental section
4.1. General information and chemicals
1
NMR data were collected on a Bruker AscendTM 400 spectrometer operating at 400 MHz for H and
100 MHz for 13C. The concentration of all samples was 20 mg / 0.5 mL of CDCl3. The NMR data were
recorded at 300 K, with chemical shifts (δ) reported in parts per million (ppm) relative to TMS (δH
0.00 and δC 0.0) used as the internal standard, or residual chloroform (δH 7.28 and δC 77.2), and
coupling constants (J) in hertz. The multiplicity listed as follow: s = singlet, d = doublet, t = triplet, q =
quartet, q* = quintet, m = multiplet. Structures were confirmed based on NMR data including proton
and DEPTQ135. The High Resolution Electrospray Ionization Mass Spectrometry (HR-ESIMS) for
molecular weights was performed on a Q-TOF mass spectrometer, with 1 µl of each sample solution
injected onto an HPLC ProtoID-Chip-43 (43mm x 75 µm; Zorbax 300SB-18). The mobile phase
consisted of H2O/CH3CN mixture at 0.6 µl/min, with the initial concentration of 3% CH3CN increased
to 80% CH3CN over a 15 minute period. Data were collected in MS only mode, with reference
compounds (322.048121 and 1221.990637 Da) continually introduced into the system. Mass Hunter
Data Analysis software (Version B 06.00) was used to analyze the data and to determine molecular
weights. Reaction mixtures were monitored using a 200-MS GC/MS ion trap mass spectrometer or by
TLC silica gel 60 F254 plates. Gravity and flash column chromatography were performed using type
60A silica gel (60-230 mesh). Transmission Electron Microscopy (TEM) images were recorded on a FEI
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Tecnai G2 F30 Twin 300 kV / FEG Transmission Electron Microscope, equipped with Gatan cryogenic
TEM system with FEI low dose capability, total solution for 3D imaging, FEI Eagle 4 k high sensitivity
CCD camera, with a Point Resolution of 0.24 nm, Line Resolution of 0.144 nm, and information limit
of 0.15 nm.
All chemicals and solvents were purchased from major chemical suppliers, and were used without
further purification unless stated otherwise.
4.2. Methods
4.2.1 Preparation of the nano-dispersed catalysts
The general preparation procedure for the catalysts was based on a modified version of previously
reported methods,45, 53 and consisted in stirring vigorously a given alkoxysilane to be used as a matrix
in about 10 mL of 0.05 M HCl until the solution become homogeneous. Then potassium
tetrachloroplatinate (K2PtCl4, 0.02 equiv) dissolved in 30 mL of isopropanol: H2O (1: 4) is added, and
the mixture stirred until a light-orange homogeneous solution is obtained. About 6 to 10 mL of 1 M,
NaOH (0.05 eqv) was added to the mixture and stirred until gelation (which was fast for MTES, HTEOS
and ETES, but took up to an hour for TEVS and PTES). The resulting light-orange homogeneous and
transparent gel was allowed to air dry for 4 days. The dark-blue xerogel obtained was reduced with a
solution of sodium borohydride in 50 mL THF: H2O (1:1). Pt: NaBH4 = 1: 10, the resulting material was
washed with 2 portions of 100 mL of distilled water, and one portion of 100 mL THF, air-dried at room
temperature, and was ready to be used.45
Preparation of the Pt@MTES catalyst
A mixture of methyltriethoxysilane (MTES: 30 g, 168.3 mmol) and 10 mL of 0.05 M HClaq was stirred
until the solution became homogeneous, and K2PtCl4 (n = 3.37 mmol, m = 1.40 g) dissolved in 30 mL
of isopropanol: H2O (1: 4) was added. The mixture was stirred until a complete homogeneity is
achieved, 8.4 mL of 1 M NaOH was added, and the mixture was further stirred until gelation. The light-
orange xerogel obtained was air-dried for 4 days, reduced with a solution of sodium borohydride,
washed and air-dried at room temperature as above described.
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Preparation of the Pt@HTEOS catalyst
A mixture of triethoxysilane (HTEOS: 30 g, 182.6 mmol) and 10 mL of 0.05 M HClaq was stirred until
the solution became homogeneous, and K2PtCl4 (n = 3.65 mmol, m = 1.52 g) dissolved in 30 mL of
isopropanol: H2O (1: 4) was added. The mixture was stirred until a complete homogeneity is achieved,
9.1 mL of 1 M NaOH was added, and the mixture was further stirred until gelation. The light-orange
xerogel obtained was air-dried for 4 days, reduced with a solution of sodium borohydride, washed
and air-dried at room temperature as above described.
Preparation of the Pt@ETES catalyst
A mixture of ethyltriethoxysilane (ETES: 30 g, 156.0 mmol) and 10 mL of 0.05 M HClaq was stirred until
the solution became homogeneous, and K2PtCl4 (n = 3.12 mmol, m = 1.29 g) dissolved in 30 mL of
isopropanol: H2O (1: 4) was added. The mixture was stirred until a complete homogeneity is achieved,
7.8 mL of 1 M NaOH was added, and the mixture was further stirred until gelation. The light-orange
xerogel obtained was air-dried for 4 days, reduced with a solution of sodium borohydride, washed
and air-dried at room temperature as above described.
Preparation of the Pt@TEVS catalyst
A mixture of triethoxyvinylsilane (TEVS: 30 g, 157.6 mmol) and 10 mL of 0.05 M HClaq was stirred until
the solution became homogeneous, and K2PtCl4 (n = 3.15 mmol, m = 1.31 g) dissolved in 30 mL of
isopropanol: H2O (1: 4) added. The mixture was stirred until a complete homogeneity is achieved, 7.9
mL of 1 M NaOH was added, and the mixture was further stirred until gelation. The light-orange
xerogel obtained was air-dried for 4 days, reduced with a solution of sodium borohydride, washed
and air-dried at room temperature as above described.
Preparation of the Pt@PTES catalyst
A mixture of propyltriethoxysilane (PTES: 30 g, 145.4 mmol) and 10 mL of 0.05 M HClaq was stirred
until the solution became homogeneous, and K2PtCl4 (n = 2.91 mmol, m = 1.21 g) dissolved in 30 mL
of isopropanol: H2O (1: 4) was added. The mixture was stirred until a complete homogeneity is
achieved, 7.3 mL of 1 M NaOH was added, and the mixture was further stirred until gelation. The light-
orange xerogel obtained was air-dried for 4 days, reduced with a solution of sodium borohydride,
washed and air-dried at room temperature as above described.
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4.2.2 Preparation and characterization of compounds
Most reactions were setup in a gram-scale, using 1 g of the olefins, 1.2 eqv. of triethoxysilane and
either 1 mol% of the nano-dispersed catalyst or 10-4 eqv of the Speier’s catalyst, under a nitrogen
saturated environment. The reaction with the Speier’s catalyst was run under neat condition, and
heated at 140 oC for 18 h, while toluene was used as a solvent for the reaction with the nano-dispersed
o
catalyst, and heated at 100 C for 18 h. Each reaction mixture was analyzed by GC-MS and TLC, and
purified on a CombiFlash apparatus using a gradient elution of hexane and ethyl acetate, or by column
chromatography.
4.2.2.1. Triethoxy(octadecyl)silane (1)
Octadecene (1g, 3.96 mmol) and triethoxysilane (0.78 g, 4.75 mmol) were stirred and heated in the
presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (87.6 mg, 3.96
10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol (7.33
μL, 3.96 10-7 mol) under neat conditions at 140 oC, both under a nitrogen environment. The reaction
mixture, after the removal of the solvent under a reduced pressure on a rotavap (if applicable) was
then purified on a silica gel column using a mixture of hexanes – ethyl acetate (95: 5), to produce the
1
expected compound as a clear oil. Pt@MTES (1.05 g, 64%), Speier’s catalyst (1.12 g, 68%). H NMR
(400 MHz, CDCl3): δ (ppm) 0.63 (2H, t, J = 8.0 Hz), 0.88 (3H, t, J = 6.8 Hz), 1.22 (9H, t, J = 6.8 Hz), 1.26
(30H, m), 1.41 (2H, m), 3.81 (6H, q, J = 6.8 Hz). 13C NMR (100 MHz, CDCl3): δ (ppm) 10.5, 14.2, 18.3,
22.8, 22.9, 29.4, 29.5, 29.7, 29.8, 29.9, 32.0, 33.3, 58.3. HRMS (ESI/Q-TOF): [M + H]+ Calcd for
C24H53O3Si, 417.3758; Found 417.3757.
4.2.2.2. Triethoxy[3-(octadecyloxy)propyl]silane (2)
1-Allyloxyoctadecane (1 g, 3.22 mmol) (obtained through a Williamson reaction59-61 between 1-
bromooctadecane and allyl alcohol) and triethoxysilane (0.63 g, 3.86 mmol) were stirred and heated
in the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (71.2
mg, 3.21 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(5.96 μL, 3.22 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a silica gel column using a mixture of hexanes – ethyl acetate (97.5:
2.5), to produce the expected compound as a clear oil. Pt@MTES (1.04 g, 68%), Speier’s catalyst (1.07
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g, 70%). 1H NMR (400 MHz, CDCl3): δ (ppm) 0.67 (2H, t, J = 8.0 Hz), 0.88 (3H, t, J = 7.2 Hz), 1.22 (9H, t,
J = 7.2 Hz), 1.26 (30H, m), 1.56 (2H, m), 1.70 (2H, m), 3.38 (4H, q, J = 6.4 Hz), 3.82 (6H, q, J = 6.8 Hz).
13C NMR (100 MHz, CDCl3): δ (ppm) 6.5, 14.2, 18.4, 22.7, 23.0, 26.2, 29.4, 29.5, 29.6, 29.7, 29.8, 31.9,
58.3, 70.9, 73.1. HRMS (ESI/Q-TOF): [M + Na]+ Calcd for C27H58NaO4Si 497.3997; Found 497.3999.
4.2.2.3. [10-(Decyloxy)decyl]triethoxysilane (3)
10-Decyloxydec-1-ene (1 g, 3.37 mmol) (obtained through a Williamson reaction59-61 between 1-
bromodecane and dec-9-en-1-ol) and triethoxysilane (0.66 g, 4.05 mmol) were stirred and heated in
the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (74.6 mg,
o
3.37 10-5 mol) in toluene at 100 C, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(6.24 μL, 3.37 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a silica gel column using a mixture of hexanes – ethyl acetate (97: 3),
to produce the expected compound as a clear oil. Pt@MTES (1.02 g, 65%), Speier’s catalyst (0.99 g,
64%). 1H NMR (400 MHz, CDCl3): δ (ppm) 0.62 (2H, t, J = 8.0 Hz), 0.88 (3H, t, J = 7.2 Hz), 1.23 (9H, t, J
= 7.2 Hz), 1.27 (28H, m), 1.56 (4H, m), 3.86 (4H, t, J = 6.8 Hz), 3.81 (6H, q, J = 6.8 Hz). 13C NMR (100
MHz, CDCl3): δ (ppm) 10.4, 14.2, 18.4, 22.7, 22.8, 26.3, 29.3, 29.5, 29.6, 29.7, 29.9, 32.0, 33.2, 58.3,
71.0. HRMS (ESI/Q-TOF): [M + H]+ Calcd for C26H57O4Si 461.4021; Found 461.4019.
4.2.2.4. [3-(cyclohexyloxy)propyl]triethoxysilane (4)
Allyloxycyclohexane (1 g, 7.13 mmol) (obtained through a Williamson reaction59-61 between
cyclohexanol and allylbromide) and triethoxysilane (1.41 g, 8.56 mmol) were stirred and heated in the
presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (156 mg, 7.13
10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol (13.2
μL, 7.13 10-7 mol) under neat conditions at 140 oC, both under a nitrogen environment. The reaction
mixture, after the removal of the solvent under a reduced pressure on a rotavap (if applicable) was
then purified on a silica gel column using a mixture of hexanes – ethyl acetate (97.5: 2.5), to produce
the expected compound as a clear oil. Pt@MTES (1.33 g, 61%), Speier’s catalyst (1.46 g, 67%). 1H NMR
(400 MHz, CDCl3): δ (ppm) 0.64 (2H, t, J = 8.4 Hz), 1.22 (9H, t, J = 7.2 Hz), 1.24 (5H, m), 1.54 (1H, m),
1.70 (4H, m), 1.89 (2H, m), 3.21 (1H, m), 3.41 (2H, t, J = 7.2 Hz), 3.82 (6H, q, J = 7.2 Hz). 13C NMR (100
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MHz, CDCl3): δ (ppm) 6.6, 18.4, 23.5, 24.3, 25.9, 32.4, 58.3, 70.2, 77.4. HRMS (ESI/Q-TOF): [M + Na]+
Calcd for C15H32NaO4Si 327.1962; Found 327.1973.
4.2.2.5. Triethoxy[3-(oxiran-2-ylmethoxy)propyl]silane (5)
Allyl glycidyl ether (1 g, 8.76 mmol) and triethoxysilane (1.73 g, 10.5 mmol) were stirred and heated
in the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (194
mg, 8.76 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(16.2 μL, 8.76 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a silica gel column using a mixture of hexanes – ethyl acetate (97.5:
2.5), to produce the expected compound as a clear oil. Pt@MTES (1.68 g, 69%), Speier’s catalyst (1.61
g, 66%). 1H NMR (400 MHz, CDCl3): δ (ppm) 0.65 (2H, t, J = 8.0 Hz), 1.22 (9H, t, J = 7.2 Hz), 1.71 (2H,
m), 2.61 (1H, dd, J = 5.2 and 6.3 Hz), 2.79 (1H, dd, J = 5.2 and 6.3 Hz), 3.14 (1H, m), 3.40 (1H, dd, J =
5.6 and 6.0 Hz), 3.48 (2H, m), 3.71 (1H, dd, J = 11.6 and 3.2 Hz), 3.84 (6H, q, J = 7.6 Hz) . 13C NMR (100
MHz, CDCl3): δ (ppm) 6.5, 18.3, 23.0, 44.4, 50.9, 58.4, 71.4, 73.8. HRMS (ESI/Q-TOF): [M + Na]+ Calcd
for C12H26NaO5Si 301.1442; Found 301.1457.
4.2.2.6. 4-[2-(triethoxysilyl)ethyl]aniline (6)
4-Vinylaniline (1 g, 8.39 mmol) and triethoxysilane (1.65 g, 10.07 mmol) were stirred and heated in
the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (185.6
mg, 8.39 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(15.5 μL, 8.39 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the
polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (9: 1). The compound came
out in 12 minutes as a clear oily material. Pt@MTES (944 mg, 40%), Speier’s catalyst (438 mg, 18%).
1H NMR (400 MHz, CDCl3): δ (ppm) 0.95 (2H, t, J = 8.8 Hz), 1.23 (9H, t, J = 6.8 Hz), 2.63 (2H, t, J = 8.8
Hz), 3.54 (2H, brs), 3.81 (6H, q, J = 7.2 Hz), 6.61 (2H, d, J = 8.0 Hz), 7.00 (2H, d, J = 8.0 Hz). 13C NMR
(100 MHz, CDCl3): δ (ppm) 12.7, 18.3, 27.9, 58.2, 115.3, 128.5, 134.8, 144.1. HRMS (ESI/Q-TOF): [M +
H]+ Calcd for C14H26NO3Si 284.1676; Found 284.1676.
4.2.2.7. Phenethyl 4-(triethoxysilyl)butanoate (7)
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Phenethyl but-3-enoate (1 g, 5.26 mmol) (obtained through the esterification of but-3-enoyl chloride
with Phenethyl alcohol) and triethoxysilane (1.04 g, 6.31 mmol) were stirred and heated in the
presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (116 mg, 5.27
10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol (9.73
μL, 5.27 10-7 mol) under neat conditions at 140 oC, both under a nitrogen environment. The reaction
mixture, after the removal of the solvent under a reduced pressure on a rotavap (if applicable) was
then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the polarity ranging
from pure hexane to a mixture of hexane-ethyl acetate (9: 1). The compound came out in 6.1 minutes
1
as a clear oily material. Pt@MTES (1.04 g, 56%), Speier’s catalyst (990 mg, 53%). H NMR (400 MHz,
CDCl3): δ (ppm) 0.64 (2H, t, J = 8.1 Hz), 1.22 (9H, t, J = 6.8 Hz), 1.74 (2H, m), 2.34 (2H, t, J = 7.2 Hz),
2.92 (2H, t, J = 7.2 Hz), 3.81 (6H, q, J = 6.8 Hz), 4.28 (2H, t, J = 7.2Hz), 7.22 (2H, m), 7.29 (3H, m). 13
C
NMR (100 MHz, CDCl3): δ (ppm) 10.1, 18.3, 18.6, 35.2, 37.2, 58.2, 64.7, 126.5, 128.5, 128.9, 137.9,
173.4. HRMS (ESI/Q-TOF): [M + H]+ Calcd for C18H31O5Si 355.1935; Found 355.1952.
4.2.2.8. Phenethyl 11-(triethoxysilyl)undecanoate (8)
Phenethyl undec-10-enoate (1 g, 3.47 mmol) (obtained through the esterification of undec-10-enoyl
chloride with Phenethyl alcohol) and triethoxysilane (0.68 g, 4.16 mmol) were stirred and heated in
the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (76.7 mg,
o
3.47 10-5 mol) in toluene at 100 C, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(6.42 μL, 3.47 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the
polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (9: 1). The compound came
out in 6.0 minutes as a clear oily material. Pt@MTES (859 mg, 55%), Speier’s catalyst (866 mg, 55%).
1H NMR (400 MHz, CDCl3): δ (ppm) 0.63 (2H, t, J = 8.0 Hz), 1.22 (9H, t, J = 6.8 Hz), 1.26 (12H, m), 1.40
(2H, m), 1.58 (2H, m), 2.27 (2H, t, J = 7.6 Hz), 2.93 (2H, t, J = 6.8 Hz), 3.81 (6H, t, J = 7.2 Hz), 4.28 (2H,
t, J = 7.2 Hz), 7.21 (2H, m), 7.29 (3H, m). 13C NMR (100 MHz, CDCl3): δ (ppm) 10.4, 18.5, 22.8, 25.0,
29.1, 29.3, 29.4, 29.5, 33.2, 34.1, 34.3, 35.2, 58.3, 64.7,126.5, 128.5, 128.9, 137.9, 173.8. HRMS (ESI/Q-
TOF): [M + H]+ Calcd for C25H45O5Si 453.3031; Found 453.3021.
4.2.2.9. Triethoxy(3-phenethoxypropyl)silane (9)
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[2-(Allyloxy)ethyl]benzene (1 g, 6.16 mmol) (obtained through a Williamson reaction59-61 between 2-
phenylethanol and allyl bromide), and triethoxysilane (1.22 g, 7.40 mmol) were stirred and heated in
the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (136 mg,
o
6.16 10-5 mol) in toluene at 100 C, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(11.4 μL, 6.16 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the
polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came
out in 6.3 minutes as a clear oily material. Pt@MTES (1.09 g, 54%), Speier’s catalyst (1.16 g, 58%). 1H
NMR (400 MHz, CDCl3): δ (ppm) 0.63 (2H, t, J = 8.0 Hz), 1.22 (9H, t, J = 7.2 Hz), 1.69 (2H, m), 2.88 (2H,
t, J = 7.2 Hz), 3.42 (2H, t, J = 6.8 Hz), 3.63 (2H, t, J = 7.2 Hz), 3.80 (6H, q, J = 6.8 Hz), 7.26 (5H, m). 13C
NMR (100 MHz, CDCl3): δ (ppm) 6.4, 18.3, 23.1, 36.6, 58.4, 71.7, 73.2, 124.3, 126.1, 128.9, 139.3.
HRMS (ESI/Q-TOF): [M + Na]+ Calcd for C17H30NaO4Si 349.1806; Found 349.1811.
4.2.2.10. [3-(benzyloxy)propyl]triethoxysilane (10)
(Allyloxymethyl)benzene (1 g, 6.75 mmol) (obtained through a Williamson reaction59-61 between
benzyl chloride and allyl alcohol) and triethoxysilane (1.33 g, 8.10 mmol) were stirred and heated in
the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (149 mg,
o
6.75 10-5 mol) in toluene at 100 C, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(12.50 μL, 6.75 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the
polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came
out in 6.2 minutes as a clear oily material. Pt@MTES (1.11 g, 53%), Speier’s catalyst (1.16 g, 55%). 1H
NMR (400 MHz, CDCl3): δ (ppm) 0.67 (2H, t, J = 8.0 Hz), 1.22 (9H, t, J = 6.8 Hz), 1.74 (2H, m), 3.50 (2H,
t, J = 6.8 Hz), 3.81 (6H, q, J = 7.2 Hz), 4.50 (2H, s), 7.26 (5H, m). 13C NMR (100 MHz, CDCl3): δ (ppm)
6.6, 18.3, 23.0, 58.4, 72.6, 127.0, 127.5, 128.3, 138.8. HRMS (ESI/Q-TOF): [M + H]+ Calcd for C16H27O4Si
313.1830; Found 313.1843.
4.2.2.11. Triethoxy[3-(naphthalen-2-yloxy)propyl]silane (11)
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2-(Allyloxy)naphthalene (1 g, 5.43 mmol) (obtained through a Williamson reaction59-61 between 2-
naphthol and allyl bromide) and triethoxysilane (1.07 g, 6.51 mmol) were stirred and heated in the
presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (120 mg, 5.43
10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol (10.1
μL, 5.43 10-7 mol) under neat conditions at 140 oC, both under a nitrogen environment. The reaction
mixture, after the removal of the solvent under a reduced pressure on a rotavap (if applicable) was
then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the polarity ranging
from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came out in 5.5 minutes
1
as a clear oily material. Pt@MTES (1.01 g, 53%), Speier’s catalyst (1.02 g, 54%). H NMR (400 MHz,
CDCl3): δ (ppm) 0.81 (2H, t, J = 8.4 Hz), 1.23 (9H, t, J = 6.8 Hz), 1.98 (2H, m), 3.84 (6H, q, J = 6.8 Hz),
4.06 (2H, t, J = 6.8 Hz), 7.14 (2H, m), 7.32 (1H, m), 7.41 (1H, m), 7.72 (3H, m). 13C NMR (100 MHz,
CDCl3): δ (ppm) 6.9, 18.3, 22.9, 58.6, 70.0, 106.7, 119.0, 123.5, 126.3, 126.7, 127.7, 129.3, 134.8,
157.2. HRMS (ESI/Q-TOF): [M + Na]+ Calcd for C19H28NaO4Si 371.1649; Found 371.1660.
4.2.2.12.Triethoxy(3-phenoxypropyl)silane (12a)
Allyloxybenzene (1 g, 7.45 mmol) (obtained through a Williamson reaction59-61 between phenol and
allyl bromide) and triethoxysilane (1.47 g, 8.94 mmol) were stirred and heated in the presence of
either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (165 mg, 7.45 10-5 mol) in
toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol (13.8 μL, 7.45 10-7
mol) under neat conditions at 140 oC, both under a nitrogen environment. The reaction mixture, after
the removal of the solvent under a reduced pressure on a rotavap (if applicable) was then purified on
a CombiFlash using a gradient of hexane – ethyl acetate, with the polarity ranging from pure hexane
to a mixture of hexane-ethyl acetate (95: 5). The compound came out in 5.3 minutes as a clear oily
material. Pt@MTES (1.22 g, 55%), Speier’s catalyst (1.37 g, 62%). 1H NMR (400 MHz, CDCl3): δ (ppm)
0.77 (2H, t, J = 8.0 Hz), 1.23 (9H, t, J = 7.2 Hz), 1.90 (2H, m), 3.83 (6H, q, J = 7.2 Hz), 3.94 (2H, t, J = 6.8
Hz), 6.91 (3H, m), 7.25 (2H, m). 13C NMR (100 MHz, CDCl3): δ (ppm) 6.8, 18.3, 22.9, 58.6, 69.8, 114.5,
120.5, 129.4, 159.1. HRMS (ESI/Q-TOF): [M + H]+ Calcd for C15H27O4Si 299.1673; Found 299.1675.
4.2.2.13. [3-(4-chlorophenoxy)propyl]triethoxysilane (12b)
1-(Allyloxy)-4-chlorobenzene (1 g, 5.93 mmol) (obtained through a Williamson reaction59-61 between
4-chlorophenol and allyl bromide) and triethoxysilane (1.17 g, 7.12 mmol) were stirred and heated in
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the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (131 mg,
5.93 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(11.0 μL, 5.93 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the
polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came
out in 6.1 minutes as a clear oily material. Pt@MTES (1.23 g, 62%), Speier’s catalyst (1.17 g, 59%). 1H
NMR (400 MHz, CDCl3): δ (ppm) 0.75 (2H, t, J = 8.0 Hz), 1.22 (9H, t, J = 7.2 Hz), 1.87 (2H, m), 3.82 (6H,
q, J = 6.8 Hz), 3.90 (2H, t, J = 6.8 Hz), 6.81 (2H, d, J = 9.2 Hz), 7.20 (2H, d, J = 8.8 Hz). 13C NMR (100 MHz,
CDCl3): δ (ppm) 6.5, 18.2, 22.7, 58.4, 70.2, 115.9, 125.3, 129.5, 157.7. HRMS (ESI/Q-TOF): [M + H]+
Calcd for C15H26ClO4Si 333.1283; Found 333.1280.
4.2.2.14. [3-(2-chlorophenoxy)propyl]triethoxysilane (12c)
1-(Allyloxy)-2-chlorobenzene (1 g, 5.93 mmol) (obtained through a Williamson reaction59-61 between
4-chlorophenol and allyl bromide) and triethoxysilane (1.17 g, 7.12 mmol) were stirred and heated in
the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (131 mg,
5.93 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(11.0 μL, 5.93 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the
polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came
1
out in 6.4 minutes as a clear oily material. Pt@MTES (1.12 g, 57%), Speier’s catalyst (1.29 g, 65%). H
NMR (400 MHz, CDCl3): δ (ppm) 0.75 (2H, t, J = 8.0 Hz), 1.21 (9H, t, J = 7.2 Hz), 3.83 (6H, q, J = 6.8 Hz),
3.92 (2H, t, J = 6.8 Hz), 6.78 (1H, d, J = 7.2 Hz), 6.90 (2H, m), 7.14 (1H, t, J = 7.6 Hz). 13C NMR (100 MHz,
CDCl3): δ (ppm) 6.5, 18.3, 22.7, 58.4, 70.1, 113.0, 114.9, 120.6, 130.2, 134.8, 159.9. HRMS (ESI/Q-TOF):
[M + H]+ Calcd for C15H25ClO4Si 333.1283; Found 333.1271.
4.2.2.15. [3-(4-bromophenoxy)propyl]triethoxysilane (12d)
1-(Allyloxy)-4-bromobenzene (1 g, 4.69 mmol) (obtained through a Williamson reaction59-61 between
4-bromphenol and allyl bromide) and triethoxysilane (0.93 g, 5.63 mmol) were stirred and heated in
the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (104 mg,
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o
4.69 10-5 mol) in toluene at 100 C, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(8.69 μL, 4.69 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the
polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came
out in 6.5 minutes as a clear oily material. Pt@MTES (1.03 g, 58%), Speier’s catalyst (0.983 g, 56%). 1H
NMR (400 MHz, CDCl3): δ (ppm) 0.76 (2H, t, J = 8.0 Hz), 1.23 (9H, t, J = 7.2 Hz), 1.88 (2H, m), 3.85 (6H,
q, J = 6.8 Hz), 3.91 (2H, t, J = 6.8 Hz), 6.77 (2H, d, J = 8.8 Hz), 7.35 (2H, d, J = 8.8 Hz). 13C NMR (100 MHz,
CDCl3): δ (ppm) 6.5, 18.2, 22.7, 58.4, 70.1, 112.6, 116.4, 132.2, 158.2. HRMS (ESI/Q-TOF): [M + Na]+
Calcd for C15H25BrNaO4Si 399.0598; Found 399.0595.
4.2.2.16. [3-(3,4-dichlorophenoxy)propyl]triethoxysilane (12e)
4-(Allyloxy)-1,2-dichlorobenzene (1 g, 4.92 mmol) (obtained through a Williamson reaction59-61
between 3,4-dichlorophenol and allyl bromide) and triethoxysilane (0.97 g, 5.91 mmol) were stirred
and heated in the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum
content (109 mg, 4.92 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O
o
in isopropanol (9.12 μL, 4.92 10-7 mol) under neat conditions at 140 C, both under a nitrogen
environment. The reaction mixture, after the removal of the solvent under a reduced pressure on a
rotavap (if applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate,
with the polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The
compound came out in 7.4 minutes as a clear oily material. Pt@MTES (1.05 g, 58%), Speier’s catalyst
(836 mg, 46%). 1H NMR (400 MHz, CDCl3): δ (ppm) 0.75 (2H, t, J = 8.0 Hz), 1.23 (9H, t, J = 7.2 Hz), 1.89
(2H, m), 3.83 (6H, q, J = 7.2 Hz), 3.86 (2H, t, J = 6.8 Hz), 6.74 (1H, dd, J = 9.2 and 2.8 Hz), 6.98 (1H, d, J
= 2.8Hz), 7.29 (1H, d, J = 9.2 Hz). 13C NMR (100 MHz, CDCl3): δ (ppm) 6.6, 18.3, 22.9, 58.6, 70.5, 114.6,
116.3, 123.8, 130.6, 132.9, 158.3. HRMS (ESI/Q-TOF): [M + Na]+ Calcd for C15H24Cl2NaO4Si 389.0713;
Found 389.0714.
4.2.2.17. Triethoxy[3-(p-tolyloxy)propyl]silane (12f)
1-(Allyloxy)-4-methylbenzene (1 g, 6.75 mmol) (obtained through a Williamson reaction59-61 between
1-bromooctadecane and allyl alcohol) and triethoxysilane (1.33 g, 8.10 mmol) were stirred and heated
in the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (149
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mg, 6.75 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O in isopropanol
o
(12.5 μL, 6.75 10-7 mol) under neat conditions at 140 C, both under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap (if
applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the
polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came
out in 6.0 minutes as a clear oily material. Pt@MTES (1.27 g, 60%), Speier’s catalyst (1.21 g, 57%). 1H
NMR (400 MHz, CDCl3): δ (ppm) 0.77 (2H, t, J = 8.0 Hz), 1.23 (9H, t, J = 7.2 Hz), 1.88 (2H, m), 2.28 (3H,
s), 3.83 (6H, q, J = 7.2 Hz), 3.91 (2H, t, J = 6.4 Hz), 6.79 (2H, d, J = 8.8 Hz), 7.06 (2H, d, J = 8.8 Hz). 13C
NMR (100 MHz, CDCl3): δ (ppm) 6.5, 18.5, 20.6, 22.8, 58.4, 70.0, 114.6, 129.8, 130.0, 157.0. HRMS
(ESI/Q-TOF): [M + Na]+ Calcd for C16H28NaO4Si 335.1649; Found 335.1645.
4.2.2.18. Triethoxy[3-(4-isopropylphenoxy)propyl]silane (12g)
1-(Allyloxy)-4-isopropylbenzene (1 g, 5.67 mmol) (obtained through a Williamson reaction59-61
between 1-bromooctadecane and allyl alcohol) and triethoxysilane (1.12 g, 6.81 mmol) were stirred
and heated in the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum
content (125 mg, 5.67 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O
o
in isopropanol (10.5 μL, 5.68 10-7 mol) under neat conditions at 140 C, both under a nitrogen
environment. The reaction mixture, after the removal of the solvent under a reduced pressure on a
rotavap (if applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate,
with the polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The
compound came out in 6.3 minutes as a clear oily material. Pt@MTES (1.21 g, 63%), Speier’s catalyst
(1.04 g, 54%). 1H NMR (400 MHz, CDCl3): δ (ppm) 0.76 (2H, t, J = 8.0 Hz), 1.22 (9H, t, J = 6.8 Hz), 1.23
(6H, d, J = 7.2 Hz), 1.89 (2H, m), 2.85 (1H, m), 3.84 (6H, q, J = 7.2 Hz), 3.92 (2H, t, J = 6.4 Hz), 6.82 (2H,
d, J = 8.4 Hz), 7.12 (2H, d, J = 8.8 Hz). 13C NMR (100 MHz, CDCl3): δ (ppm) 6.6, 18.3, 23.1, 24.2, 33.3,
58.6, 70.2, 114.4, 127.2, 141.0, 157.3. HRMS (ESI/Q-TOF): [M + H]+ Calcd for C18H33O4Si 341.2143;
Found 341.2149.
4.2.2.19. Triethoxy[3-(3-methoxyphenoxy)propyl]silane (12h)
1-(Allyloxy)-3-methoxybenzene (1 g, 6.09 mmol) (obtained through a Williamson reaction59-61
between 3-methoxyphenol and allyl bromide) and triethoxysilane (1.20 g, 7.31 mmol) were stirred
and heated in the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum
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content (135 mg, 6.09 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O
o
in isopropanol (11.3 μL, 6.09 10-7 mol) under neat conditions at 140 C, both under a nitrogen
environment. The reaction mixture, after the removal of the solvent under a reduced pressure on a
rotavap (if applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate,
with the polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The
compound came out in 6.3 minutes as a clear oily material. Pt@MTES (1.27 g, 64%), Speier’s catalyst
(1.16 g, 58%). 1H NMR (400 MHz, CDCl3): δ (ppm) 0.76 (2H, t, J = 8.0 Hz),1.23 (9H, t, J = 6.8 Hz), 1.90
(2H, m), 3.78 (3H, s), 3.83 (6H, q, J = 6.8 Hz), 3.92 (2H, t, J = 7.2 Hz), 6.47 (3H, m), 7.16 (1H, dd, J = 8.0
and 8.4 Hz). 13C NMR (100 MHz, CDCl3): δ (ppm) 6.5, 18.4, 22.8, 55.2, 58.4, 69.9, 101.0, 106.2, 106.7,
129.9, 160.4, 160.8. HRMS (ESI/Q-TOF): [M + Na]+ Calcd for C16H28NaO5Si 351.1598; Found 351.1597.
4.2.2.20. [3-(3,4-dimethylphenoxy)propyl]triethoxysilane (12i)
4-(Allyloxy)-1,2-dimethylbenzene (1 g, 6.16 mmol) (obtained through a Williamson reaction59-61
between 3,4-dimethylphenol and allyl bromide) and triethoxysilane (1.22 g, 7.40 mmol) were stirred
and heated in the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum
content (136 mg, 6.16 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O
o
in isopropanol (11.4 μL, 6.16 10-7 mol) under neat conditions at 140 C, both under a nitrogen
environment. The reaction mixture, after the removal of the solvent under a reduced pressure on a
rotavap (if applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate,
with the polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The
compound came out in 5.7 minutes as a clear oily material. Pt@MTES (1.12 g, 56%), Speier’s catalyst
(1.09 g, 54%). 1H NMR (400 MHz, CDCl3): δ (ppm) 0.77 (2H, t, J = 8.0 Hz), 1.22 (9H, t, J = 6.8 Hz), 1.88
(2H, m), 2.18 (3H, s), 2.22 (3H, s), 3.82 (6H, q, J = 7.2 Hz), 3.90 (2H, t, J = 6.8 Hz), 6.63 (1H, dd, J = 8.0
and 2.8 Hz), 6.70 (1H, d, J = 2.8 Hz), 7.00 (1H, d, J = 8.0 Hz). 13C NMR (100 MHz, CDCl3): δ (ppm) 6.6,
18.8, 20.0, 22.7, 58.4, 59.3, 69.9, 111.5, 116.2, 128.5, 130.2, 137.5, 157.5. HRMS (ESI/Q-TOF): [M +
Na]+ Calcd for C17H30NaO4Si 349.1806; Found 349.1809.
4.2.2.21. Methyl 3-[3-(triethoxysilyl)propoxy]benzoate (12j)
Methyl 3-(allyloxy)benzoate (1 g, 5.20 mmol) (obtained through a Williamson reaction59-61 between
methyl 3-hydroxybenzoate and allyl bromide) and triethoxysilane (1.03 g, 6.24 mmol) were stirred
and heated in the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum
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content (115 mg, 5.20 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O
o
in isopropanol (9.63 μL, 5.20 10-7 mol) under neat conditions at 140 C, both under a nitrogen
environment. The reaction mixture, after the removal of the solvent under a reduced pressure on a
rotavap (if applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate,
with the polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (9: 1). The compound
came out in 6 minutes as a clear oily material. Pt@MTES (1.13 g, 61%), Speier’s catalyst (1.15 g, 62%).
1H NMR (400 MHz, CDCl3): δ (ppm) 0.78 (2H, t, J = 8.4 Hz), 1.23 (9H, t, J = 7.2 Hz), 1.92 (2H, m), 3.85
(6H, q, J = 6.8 Hz), 3.91 (3H, s), 3.99 (2H, t, J = 6.8 Hz), 7.10 (1H, dd, J = 8.4 and 1.6 Hz), 7.32 (1H, t, J =
8.0 Hz), 7.55 (1H, d, J = 1.6 Hz), 7.62 (1H, d, J = 7.6 Hz). 13C NMR (100 MHz, CDCl3): δ (ppm) 6.5, 18.6,
22.7, 52.3, 58.4, 70.1, 115.0, 129.0, 121.9, 129.4, 131.4, 159.1, 167.0. HRMS (ESI/Q-TOF): [M + Na]+
Calcd for C17H28NaO6Si 379.1547; Found 379.1543.
4.2.2.22. Methyl 4-[3-(triethoxysilyl)propoxy]benzoate (12k)
Methyl 4-(allyloxy)benzoate (1 g, 5.20 mmol) (obtained through a Williamson reaction59-61 between
methyl 4-hydroxybenzoate and allyl bromide) and triethoxysilane (1.03 g, 6.24 mmol) were stirred
and heated in the presence of either 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum
content (115 mg, 5.20 10-5 mol) in toluene at 100 oC, or 10-4 eqv of a 0.054 M solution of H2PtCl6.6H2O
o
in isopropanol (9.63 μL, 5.20 10-7 mol) under neat conditions at 140 C, both under a nitrogen
environment. The reaction mixture, after the removal of the solvent under a reduced pressure on a
rotavap (if applicable) was then purified on a CombiFlash using a gradient of hexane – ethyl acetate,
with the polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The
compound came out in 8 minutes as a clear oily material. Pt@MTES (1.07 g, 58%), Speier’s catalyst
(720 mg, 39%). 1H NMR (400 MHz, CDCl3): δ (ppm) 0.77 (2H, t, J = 8.4 Hz), 1.23 (9H, t, J = 6.8 Hz), 1.93
(2H, m), 3.85 (6H, q, J = 7.2 Hz), 3.88 (3H, s), 4.00 (2H, t, J = 6.8 Hz), 6.90 (2H, d, J = 8.8 Hz), 7.96 (2H,
d, J = 8.4Hz). 13C NMR (100 MHz, CDCl3): δ (ppm) 6.5, 18.3, 22.7, 52.0, 58.5, 70.0, 114.2, 122.3, 131,8,
162.9, 166.9. HRMS (ESI/Q-TOF): [M + H]+ Calcd for C17H28NaO6Si 379.1547; Found 379.1548.
4.2.2.23. Diethoxy(methyl)(3-phenoxypropyl)silane (13)
Allyloxybenzene (0.5 g, 3.73 mmol) (obtained through a Williamson reaction59-61 between phenol and
allyl bromide) and diethoxymethyllsilane (600 mg, 4.47 mmol) were stirred and heated in the
presence of 1 mol% of the Pt@HTEOS catalyst having c.a. 6.5% platinum content (112 mg, 3.73 10-5
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mol) in toluene at 100 oC, under a nitrogen environment. The reaction mixture, after the removal of
the solvent under a reduced pressure on a rotavap, was then purified on a CombiFlash using a gradient
of hexane – ethyl acetate, with the polarity ranging from pure hexane to a mixture of hexane-ethyl
acetate (95: 5). The compound came out in 7.0 minutes as a clear oily material (547 mg, 55%). 1H NMR
(400 MHz, CDCl3): δ (ppm). 0.15 (3H, s), 0.75 (2H, t, J = 8.4Hz), 1.22 (6H, t, J = 6.8 Hz), 1.86 (2H, m),
3.78 (4H, q, J = 6.8 Hz), 3.94 (2H, t, J = 6.8 Hz), 6.92 (3H, m), 7.25 (2H, t, J = 8.2 Hz). 13C NMR (100 MHz,
CDCl3): δ (ppm) 5.6, 10.1, 18.4, 23.0, 58.1, 70.0, 114.5, 120.5, 129.4, 159.1. HRMS (ESI/Q-TOF): [M +
H]+ Calcd for C14H24NaO3Si 291.1387; Found 291.1391.
4.2.2.24. Diethyl(3-phenethoxypropyl)silane (14)
[2-(Allyloxy)ethyl]benzene (0.5 g, 3.08 mmol) (obtained through a Williamson reaction59-61 between
2-phenylethanol and allyl bromide) and diethylsilane (326 mg, 3.70 mmol) were stirred and heated in
the presence of 1 mol% of the Pt@HTEOS catalyst having c.a. 6.5% platinum content (92.5 mg, 3.08
10-5 mol) in toluene at 100 oC, under a nitrogen environment. The reaction mixture, after the removal
of the solvent under a reduced pressure on a rotavap, was then purified on a CombiFlash using a
gradient of hexane – ethyl acetate, with the polarity ranging from pure hexane to a mixture of hexane-
ethyl acetate (95: 5). The compound came out in 6.3 minutes as a clear oily material (515 g, 67%). 1H
NMR (400 MHz, CDCl3): δ (ppm). 0.59 (6H, m), 0.97 (6H, t, J = 8.0 Hz), 1.60 (2H, m), 2.91 (2H, t, J = 7.2
Hz), 3.41 (2H, t, J = 6.8 Hz), 3.63 (2H, t, J = 7.2 Hz), 7.21 – 7.28 (5H, m). 13C NMR (100 MHz, CDCl3): δ
(ppm) 2.8, 6.7, 8.4, 24.8, 36.4, 71.8, 73.6, 126.3, 128.2, 129.0, 139.1. HRMS (ESI/Q-TOF): [M-H]+ Calcd
for C15H25Osi 249.1675; Found 249.1674.
4.2.2.25. [3-(cyclohexyloxy)propyl]diethylsilane (15)
Allyloxycyclohexane (0.5 g, 3.57 mmol) (obtained through a Williamson reaction59-61 between phenol
and allyl bromide) and diethylsilane (377 mg, 4.28 mmol) were stirred and heated in the presence of
1 mol% of the Pt@HTEOS catalyst having c.a. 6.5% platinum content (107 mg, 3.57 10-5 mol) in toluene
at 100 oC, under a nitrogen environment. The reaction mixture, after the removal of the solvent under
a reduced pressure on a rotavap, was then purified on a CombiFlash using a gradient of hexane – ethyl
acetate, with the polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The
compound came out in 5.5 minutes as a clear oily material (327 mg, 33%). 1H NMR (400 MHz, CDCl3):
δ (ppm) 0.60 (6H, m), 0.98 (6H, t, J = 8.0 Hz), 1.26 (5H, m), 1.61 (1H, m), 1.67 (2H, m), 1.73 2H, q, J =
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6.9 Hz), 1.90 (2H, q, J = 7.0 Hz), 3.21 (1H, m), 3.41 (2H, t, J = 6.8 Hz), 3.66 (1H, m). 13C NMR (100 MHz,
CDCl3): δ (ppm) 2.8, 6.7, 8.2, 24.3, 25.3, 25.9, 32.4, 70.6, 77.6. HRMS (ESI/Q-TOF): [M - H]+ Calcd for
C13H27OSi 227.1831; Found 227.1835.
4.2.2.26. Triethyl(3-phenoxypropyl)silane (16)
Allyloxybenzene (0.5 g, 3.73 mmol) (obtained through a Williamson reaction59-61 between phenol and
allyl bromide) and triethylsilane (520 mg, 4.47 mmol) were stirred and heated in the presence of 1
mol% of the Pt@HTEOS catalyst having c.a. 6.5% platinum content (112 mg, 3.73 10-5 mol) in toluene
at 100 oC, under a nitrogen environment. The reaction mixture, after the removal of the solvent under
a reduced pressure on a rotavap, was then purified on a CombiFlash using a gradient of hexane – ethyl
acetate, with the polarity ranging from pure hexane to a mixture of hexane-ethyl acetate (95: 5). The
compound came out in 6.5 minutes as a clear oily material (421 mg, 45%). 1H NMR (400 MHz, CDCl3):
δ (ppm) 0.53 (6H, q, J = 8.0 Hz), 0.62 (2H, t, J = 6.9 Hz), 0.94 (9H, t, J = 8.0 Hz), 1.74 – 1.80 (2H, m), 3.90
(2H, t, J = 6.8 Hz), 6.92 (3H, m), 7.25 (2H, m). 13C NMR (100 MHz, CDCl3): δ (ppm) 3.3, 7.3, 7.9, 23.8,
70.8, 114.6, 116.5, 120.5, 129.6, 159.1. HRMS (ESI/Q-TOF): [M + H]+ Calcd for C15H27OSi 251.1826;
Found 251.1832.
4.2.2.27. (E/Z)-(1,2-diphenylvinyl)triethoxysilane (17)
Diphenylacetylene (500 mg, 2.81 mmol) and triethoxysilane (553 mg, 3.37 mmol) were stirred and
heated in the presence of 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (62
mg, 2.81 10-5 mol) in toluene at 100 oC, under a nitrogen environment. The reaction mixture, after the
removal of the solvent under a reduced pressure on a rotavap, was then purified on a CombiFlash
using a gradient of hexane – ethyl acetate, with the polarity ranging from pure hexane to a mixture of
hexane-ethyl acetate (97.5: 2.5). The compound came out in 5.7 minutes as a yellowish oily material
(669 mg, 70%). 1H NMR (400 MHz, CDCl3): δ (ppm) 1.03 (6H, t, J = 7.2 Hz), 1.19 (3H, t, J = 7.2 Hz), 3.65
(4H, q, J = 7.2 Hz), 3.83 (2H, q, J = 7.2 Hz), 7.02 – 7.20 (9H, m), 7.57 (2H, d, J = 8.2 Hz). 13C NMR (100
MHz, CDCl3): δ (ppm) 17.9, 18.2, 58.5, 58.8, 126.1, 127.7, 127.9, 128.0, 128.3, 128.5, 129.0, 129.9,
137.3, 138.4, 142.5, 145.5, 149.2. HRMS (ESI/Q-TOF): [M + H]+ Calcd for C20H27O3Si 343.1724; Found
343.1723.
4.2.2.27. (E/Z)-triethoxy(hex-3-en-3-yl)silane (18)
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Hex-3-yne (500 mg, 6.09 mmol) and triethoxysilane (1.20 g, 7.30 mmol) were stirred and heated in
the presence of 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (135 mg, 6.09
10-5 mol) in toluene at 100 oC, under a nitrogen environment. The reaction mixture, after the removal
of the solvent under a reduced pressure on a rotavap, was then purified on a CombiFlash using a
gradient of hexane – ethyl acetate, with the polarity ranging from pure hexane to a mixture of hexane-
ethyl acetate (97.5: 2.5). The compound came out in 3.7 minutes as a yellowish oily material (1.73 g,
58%). 1H NMR (400 MHz, CDCl3): δ (ppm) 0.92 (6H, m), 1.16 (9H, t, J = 6.8 Hz), 2.07 (4H, m), 3.74 (6H,
m), 6.01 (1H, t, J = 6.8 Hz). 13C NMR (100 MHz, CDCl3): δ (ppm) 12.9, 13.4, 17.2, 20.5, 21.1, 57.1, 57.4,
132.6, 146.2. GC-MS: m/z 246 (5%), 217 (3%), 200 (67%) and 163 (100%).
4.2.2.28. (Z)-(1,4-bis(benzyloxy)but-2-en-2-yl)triethoxysilane (19)
1,4-Bis(benzyloxy)but-2-yne (500 mg, 1.88 mmol) (obtained through a Williamson reaction59-61
between but-2-yne-1,4-diol and benzyl bromide) and triethoxysilane (370 mg, 2.25 mmol) were
stirred and heated in the presence of 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum
o
content (41.5 mg, 1.88 10-5 mol) in toluene at 100 C, under a nitrogen environment. The reaction
mixture, after the removal of the solvent under a reduced pressure on a rotavap, was then purified
on a CombiFlash using a gradient of hexane – ethyl acetate, with the polarity ranging from pure
hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came out in 7.4 minutes as a clear
oily material (612 mg, 76%). 1H NMR (400 MHz, CDCl3): δ (ppm) 1.98 (9H, t, J = 7.2 Hz), 3.83 (6H, q, J
= 6.8 Hz), 4.09 (2H, s), 4.18 (2H, s), 4.49 (4H, d, J = 6.8 Hz), 6.46 (1H, m), 7.2 – 7.23 (10H, m). 13C NMR
(100 MHz, CDCl3): δ (ppm) 18.3, 58.7, 67.6, 67.7, 72.6, 72.7, 127.5, 127.7, 127.8, 127.9, 128.3, 128.4,
132.9, 138.2, 138.5, 145.1. HRMS (ESI/Q-TOF): [M + H]+ Calcd for C24H35O5Si 431.2248; Found
431.2239.
4.2.2.29. (Z)-(1,4-bis(4-methylbenzyloxy)but-2-en-2-yl)triethoxysilane (20)
1,4-Bis(4-methylbenzyloxy)but-2-yne (500 mg, 1.70 mmol) (obtained through a Williamson reaction59-
61 between but-2-yne-1,4-diol and 4-methylbenzyl bromide) and triethoxysilane (335 mg, 2.04 mmol)
were stirred and heated in the presence of 1 mol% of the Pt@MTES catalyst having c.a. 8.82%
o
platinum content (37.6 mg, 1.70 10-5 mol) in toluene at 100 C, under a nitrogen environment. The
reaction mixture, after the removal of the solvent under a reduced pressure on a rotavap, was then
purified on a CombiFlash using a gradient of hexane – ethyl acetate, with the polarity ranging from
pure hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came out in 6.4 minutes as
28

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New Journal of Chemistry
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DOI: 10.1039/C8NJ01889H
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a clear oily material (548 mg, 70%). H NMR (400 MHz, CDCl3): δ (ppm) 1.21 (9H, t, J = 6.8 Hz), 2.33
(6H, s), 3.83 (6H, q, J = 6.8 Hz), 4.06 (2H, s), 4.15 (2H, d, J = 5.2 Hz), 4.44 (4H, d, J = 5.2 Hz), 6.44 (1H,
m), 7.13 (4H, d, J = 7.6 Hz), 7.20 (4H, d, J = 7.6 Hz). 13C NMR (100 MHz, CDCl3): δ (ppm) 18.2, 21.2, 58.6,
67.4, 67.5, 72.4, 72.5, 127.8, 128.0, 128.9, 129.1, 132.8, 135.1, 135.4, 137.1, 137.3, 145.2. GC-MS: m/z
458 (1%), 336 (1.5%), 290 (5.6%), 163 (100%).
4.2.2.30. (E)-triethoxy(3-phenoxyprop-1-enyl)silane (21)
(Prop-2-ynyloxy)benzene (500 mg, 3.78 mmol) (obtained through a Williamson reaction59-61 between
phenol and propargyl bromide) and triethoxysilane (370 mg, 4.54 mmol) were stirred and heated in
the presence of 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum content (83.7 mg, 3.78
10-5 mol) in toluene at 100 oC, under a nitrogen environment. The reaction mixture, after the removal
of the solvent under a reduced pressure on a rotavap, was then purified on a CombiFlash using a
gradient of hexane – ethyl acetate, with the polarity ranging from pure hexane to a mixture of hexane-
ethyl acetate (95: 5). The compound came out in 5.6 minutes as a clear oily material (811 mg, 72%).
1H NMR (400 MHz, CDCl3): δ (ppm) 1.23 (9H, t, J = 7.2 Hz), 3.86 (6H, q, J = 7.2 Hz), 4.61 (2H, m), 5.86
(1H, m), 6.01 (1H, s), 6.57 (3H, m), 7.25 (2H, m). 13C NMR (100 MHz, CDCl3): δ (ppm) 17.4, 57.7, 69.2,
113.9, 119.8, 128.5, 128.7, 138.1, 157.7. GC-MS: m/z 295 (25%), 267 (46%), 252 (100%), 163 (63%)
4.2.2.30. (E)-(3-(4-chlorophenoxy)prop-1-enyl)triethoxysilane (22)
1-chloro-4-(prop-2-ynyloxy)benzene (500 mg, 3.00 mmol) (obtained through a Williamson reaction59-
61
between 4-chlorophenol and propargyl bromide) and triethoxysilane (370 mg, 3.60 mmol) were
stirred and heated in the presence of 1 mol% of the Pt@MTES catalyst having c.a. 8.82% platinum
o
content (66.4 mg, 3.00 10-5 mol) in toluene at 100 C, under a nitrogen environment. The reaction
mixture, after the removal of the solvent under a reduced pressure on a rotavap, was then purified
on a CombiFlash using a gradient of hexane – ethyl acetate, with the polarity ranging from pure
hexane to a mixture of hexane-ethyl acetate (95: 5). The compound came out in 6.3 minutes as a clear
oily material (1.42 g, 72%). 1H NMR (400 MHz, CDCl3): δ (ppm) 1.23 (9H, t, J = 7.2 Hz), 3.86 (6H, q, 7.2
Hz), 4.58 (2H, m), 5.84 (1H, m), 6.52 (1H, m), 6.82 (2H, d, J = 8.8 Hz), 7.22 (2H, d, 8.8 Hz). 13C NMR (100
MHz, CDCl3): δ (ppm) 18.4, 58.6, 70.0, 116.0, 121.5, 128.5, 129.7, 129.8, 146.4, 157.1. GC-MS: m/z 330
(5%), 301 (20%), 163 (100%).
Conflicts of interest
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