Synthesis of Functional 3-Buten-1-ynes and 1,3-Butadienes with Silsesquioxane Moiety via Hydrosilylation of 1,3-Diynes

Article abstract of DOI:10.1002/cctc.201901082

Highly effective procedures for the addition of one or two molecules of 1-dimethylsiloxy-3,5,7,9,11,13,15-heptaisobutylpentacyclo-[9.5.1.1^3,9.1^5,15.1^7,13]octasiloxane ((HSiMe₂O)(i-Bu)₇Si₈O₁₂, (1)) to the symmetrically 1,4-disubstituted 1,3-diynes have been successfully developed for the first time. As a result, novel silsesquioxanes bearing substituents such as CH₃, t-Bu, (CH₃)₂OSi(CH₃)₃, C₆H₅, C₆H₄Br-4, C₆H₄(BO₂C₂(CH₃)₄)-4, OH, COOCH₃, and morpholino were obtained and characterized by ¹H, ¹³C, ²⁹Si NMR and mass spectrometry. Detailed optimization of reaction conditions was performed with a wide range of temperatures, in the presence of various types of catalysts and ratios of reagents, to obtain complex information about the process selectivity and develop efficient methods for synthesizing targeted compounds. It was found that precisely optimized approaches provided 3-buten-1-ynes or 1,3-butadienes with high yields, without decomposition of other reactive functionalities presented in the molecule structure. Due to the presence of reactive functional groups, the resulting compounds constituted a new silsesquioxane family characterized by unique structures and potential applications.

Full text of DOI:10.1002/cctc.201901082

Accepted Article
Title: Synthesis of functional 3-buten-1-ynes and 1,3-butadienes with
silsesquioxane moiety via hydrosilylation of 1,3-diynes
Authors: Kinga Stefanowska, Adrian Franczyk, Jakub Szyling, and
Jedrzej Walkowiak
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
to this Accepted Article as a result of editing. Readers should obtain
the VoR from the journal website shown below when it is published
to ensure accuracy of information. The authors are responsible for the
content of this Accepted Article.
To be cited as: ChemCatChem 10.1002/cctc.201901082
Link to VoR: http://dx.doi.org/10.1002/cctc.201901082
A Journal of
www.chemcatchem.org

10.1002/cctc.201901082
ChemCatChem
FULL PAPER
Synthesis of functional 3-buten-1-ynes and 1,3-butadienes with
silsesquioxane moiety via hydrosilylation of 1,3-diynes
Kinga Stefanowska[a,b], Adrian Franczyk*[a], Jakub Szyling[a,b] and Jędrzej Walkowiak*[a]
Abstract: Highly effective procedures for the addition of one or two
oxygen based core is biocompatible and non-toxic, which, with
the appropriate selection of alkenyl fragments, results in
compounds which are useful for both the medical and
molecules
of
1-dimethylsiloxy-3,5,7,9,11,13,15-
heptaisobutylpentacyclo-[9.5.1.13,9.15,15.17,13]octasiloxane
((HSiMe2O)(i-Bu)7Si8O12, (1)) to the symmetrically 1,4-disubstituted
1,3-diynes have been successfully developed for the first time. As a
result, novel silsesquioxanes bearing substituents such as CH3, t-Bu,
(CH3)2OSi(CH3)3, C6H5, C6H4Br-4, C6H4(BO2C2(CH3)4)-4, OH,
COOCH3, and morpholino were obtained and characterized by 1H,
13C, 29Si NMR and mass spectrometry. Detailed optimization of
pharmaceutical industries[2a, 3d, 4]
.
The synthetic utility of such systems remains, however,
dependent on the possibility of preparing them with high levels
of regio- and stereo-control, using versatile and easily available
methods. Due to this fact, the developing of effective synthesis
methods is highly necessary. Numerous examples of mono-, di-
reaction conditions was performed with
a
wide range of
and octa-functional silsesquioxanes have been synthesized with
5b]
temperatures, in the presence of various types of catalysts and
ratios of reagents, to obtain complex information about the process
selectivity and develop efficient methods for synthesizing targeted
compounds. It was found that precisely optimized approaches
provided 3-buten-1-ynes or 1,3-butadienes with high yields, without
decomposition of other reactive functionalities presented in the
molecule structure. Due to the presence of reactive functional
groups, the resulting compounds constituted a new silsesquioxane
family characterized by unique structures and potential applications.
good yields by silylative coupling[5], cross-metathesis[5a,
Heck[6] and Wittig[7] reactions.
,
However, the hydrosilylation of alkynes is considered to be the
most universal synthetic method for the preparation of such
systems because it allows the synthesis of di- and tri-substituted
ethenes via the addition of the Si-H fragment to both terminal
and internal (symmetrically or non-symmetrically substituted) C-
C triple bonds (C≡C)[8]. Moreover, the hydrosilylation process
can be performed in a wide range of temperatures, in different
types of solvents, under atmospheric air, using easily available
reagents, in the presence of stable and tolerable noble or earth-
abundant TM catalysts[9]. All of that makes hydrosilylation a
powerful tool which, appropriately used, can easily provide a
wide spectrum of silsesquioxanes bearing various types of
functionalities.
Therefore, we have recently reported detailed studies on the
reactivity of alkynes with (HSiMe2O)(i-Bu)7Si8O12 (1) and
(HSiMe2O)8Si8O12 in the presence of platinum catalysts[10]. By
this method, we were able to obtain a wide spectrum of new
alkenyl silsesquioxanes and spherosilicates, with different
structures and functionalities, mostly unavailable by other
methods. The excellent results of this research encouraged us
to go one step further and find out whether it is possible to
perform a selective functionalization of silsesquioxane 1 with
more complex and challenging systems, such as 1,4-
disubstituted 1,3-diynes. Although the resulting but-3-en-1-ynes
and 1,3-butadienes with silsesquioxane moiety had not been
obtained by any method before, it is clear that such compounds
would be in the great interest of researchers due to their unique
structure, physicochemical properties, and potential applications
in the synthesis of molecular and macromolecular hybrid
systems.
Introduction
Polyhedral oligomeric silsesquioxanes (POSS) are among the
most intriguing examples of well-defined, nanostructured, highly
functionalized building blocks which find applications in many
fields of the academic and industrial sciences[1]. They have been
used in the synthesis of a vast number of hybrid (co)polymers
and nanocomposites characterized by a complex composition
and different functionalities[2].
Recently, much interest has arisen around silsesquioxanes
bearing conjugated groups which are often called alkenyl-
silsesquioxanes. Up to now, they have been used in the
synthesis of porous biomaterials, liquid crystals, fuel cells and
solution-processable organic light-emitting diodes (OLED)[2a, 3]. It
has been established that the attachment of silsesquioxanes as
pendant groups onto conjugated molecules or polymers
provides materials with improved color stability, higher
brightness, and improved quantum efficiency, compared with the
similar molecules or polymers that do not bear silsesquioxane
groups. Moreover, such systems possess very good solubility in
common organic solvents and improved mechanical, thermal
properties. Not without significance is the fact that a silicon-
Results and Discussion
[a]
K. Stefanowska, Dr. A. Franczyk, Dr. J. Szyling, Dr. J. Walkowiak
Center for Advanced Technology, Adam Mickiewicz University in
Poznan, Uniwersytetu Poznańskiego 10, 61-614 Poznan, Poland
adrian.franczyk@amu.edu.pl; jedrzej.walkowiak@amu.edu.pl
K. Stefanowska, Dr. J. Szyling
On the basis of our previous experience[11] and literature reports
regarding hydrosilylation of 1,4-disubstituted 1,3-butadiynes with
silanes[12]
, reactions of nine structurally and electronically
[b]
different 1,3-diynes (2a-i) (Figure 1) with (HSiMe2O)(i-Bu)7Si8O12
(1) were performed (in the presence of platinum catalysts:
Pt2(dvs)3 (Karsted’s catalyst), Pt(PPh3)4, PtO2 and Pt/SDB (SDB-
styrene-divinylbenzene copolymer)[10b], in an air atmosphere,
Faculty of Chemistry, Adam Mickiewicz University in Poznan,
Uniwersytetu Poznańskiego 8, 61-614 Poznan, Poland.
Supporting information for this article is given via a link at the end of
the document.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201901082
ChemCatChem
FULL PAPER
without any purification of the acquired chemicals). Processes
were carried out at temperatures between 40°C and 100°C or at
room temperature. The progress of the reaction was monitored
by 1H NMR, while the process selectivity was calculated using
1H and 29Si NMR (Table 1 and 2).
During the study, a 2-fold excess of 2a was also tested.
However, after 24 hours lower conversion of Si-H bond was
observed (Table 1, entry 10).
In both of the above tests, the excess of 2,4-hexadiyne used in
the reaction was easily removed under vacuum due to its low
molecular weight and high volatility.
In the next step of the studies, Pt(PPh3)4 was tested as a
catalyst for the reaction of 1 equiv. of silsesquioxane 1 with 1
equiv. of 2,4-hexadiyne (2a). When the reaction was carried out
in the presence of 10-3 mol of Pt at 100°C, it led to a mixture of
products 3a/4a/5a = 78/5/17 (Table 1, entry 12). However, when
the temperature was decreased to 40°C and 4x10-2 mol of Pt
was used, an improvement in the reaction selectivity was
observed. The process produced only monohydrosilylated
products 3a and 4a, with a high selectivity, which reached 83%
and 17% respectively (Table 1, entry 13). Products of bisaddition
to the 2,4-hexadiyne were not detected at all.
Scheme 1. Structure of tested 1,3-diynes 2a-i.
Subsequently, we decided to check if it was possible to
selectively synthesize bishydrosilylated product 5a. To this end,
the hydrosilylation of 2a with two equivalents of silsesquioxane 1
was performed. The process was carried out in the presence of
Karstedt’s catalyst (10-4 mol Pt/mol SiH) at 100°C for 3 hours.
After this time, the mixture of products 3a/5a with selectivity
19/81 was obtained (Table 1, entry 14).
In the next step, the non-stoichiometric ratio of the reagents
(1:2a = 2.1:1) was also tested. Reactions were carried out in the
presence of the Pt2(dvs)3 in the amounts of 9.5x10-5 and 9.5x10-4
mol of Pt per mol of SiH, respectively (Table 1, entries 15 and
16). The conversions were complete after 24 hours in both
processes. However, this modification did not have a positive
impact on the selectivity of the formation of product 5a, which
reached only 71% and 69% respectively. Moreover, the
formation of products 3a and 6a was also observed.
Application of the higher excess of 1 to 2a equal to 2.3:1,
allowed for the elimination of the product 3a, and resulted in the
exclusive synthesis of disubstituted products 5a/6a with a ratio
91/9 (Table 1, entry 17). It was also found that the lowering of
the reaction temperature to 60°C slightly increased the
selectivity of the formation of 5a from 91% to 94% (Table 1,
entries 17 and 18). The lowest selectivity of the formation of
product 5a was found when Pt(PPh3)4 was applied as a catalyst
(Table 1, entry 19).
At the beginning of the study, a detailed optimization of the
reaction conditions allowing for the selective synthesis of
desirable mono- (3) and bishydrosilylated (5) products was
carried out. As a model reaction, the hydrosilylation of 2,4-
hexadiyne (2a) with silsesquioxane 1 was selected. The linear,
free steric structure of 2a makes the modification of only one C-
C triple bond in its structure very challenging since the addition
of the second molecule of silsesquioxane 1 to the second C≡C
bond also occurs very effectively. The optimization of the
reaction conditions was done using different ratios of Pt2(dvs)3
and Pt(PPh3)4 catalysts at 40°C, 100°C and room temperature. It
was found that synthesis of the monohydrosilylated product with
uses of the stoichiometric ratio of the reagents in the presence
of Pt2(dvs)3 (4x10-5 mol of Pt) at 100°C led to the obtaining of a
mixture of products 3a, 4a and 5a = 59/3/38. The conversion of
the Si-H bond reached 93% after 48 hours (Table 1, entry 1).
An increase in the concentration of the catalyst from 4x10-5 to
4x10-2 mol of Pt reduced the reaction time to 30 minutes and
improved the selectivity of the process (Table 1, entries 1-4).
When the reaction was carried out in the presence of 4x10-2 mol
Pt/mol SiH, it allowed monoadducts 3a and 4a to be selectively
obtained with a ratio equal to 76/24. Formation of product 5a
was not detected (Table 1, entry 4).
Subsequently, the concentration of the solution was increased to
ms1/Vtol.= 5 mg mL-1 (Table 1, entry 5) and one equivalent of
silsesquioxane 1 was added to the reaction mixture in five
portions at 30-minute intervals (Table 1, entry 6). However,
neither of these attempts improved the reaction selectivity. After
24 hours, the mixture of products 3a, 4a and 5a was formed with
a ratio equal to 52/5/43 and 57/8/35, respectively. Moreover, in
both cases, the conversion of the reagents was incomplete. A
similar result was obtained for the reaction carried out at 40°C
and room temperature (Table 1, entries 7-9). Additionally, the
time of these reactions was extended compared to the
processes carried out with the same amount of the catalyst at
100°C.
Based on the results of the performed experiments, in the next
step, mono- and bishydrosilylations of a wide spectrum of 1,3-
butadiynes, such as: 2,2,7,7-tetramethyl-3,5-octadiyne (2b), 1,4-
(1,1-dimethyloxy-trimethysilyl)buta-1,3-diyne
(2c),
1,4-
diphenylbuta-1,3-diyne (2d), 1,4-dibromophenyl-1,3-butadiyne
(2e), 1,4-di(phenylboronic acid pinacol ester)-1,3-butadiyne (2f),
1,4-bis(1-hydroxycyclohexyl)-1,3-butadiyne
(2g),
1,6-
bis(morpholino)-2,4-hexadiyne (2h) and 10,12-docosadiyndioic
acid dimethyl ester (2i), was examined.
The monohydrosilylation of bulky 2,2,7,7-tetramethyl-3,5-
octadiyne (2b) and 1,4-(1,1-dimethyloxy-trimethysilyl)buta-1,3-
diyne (2c) was performed with the application of Karstedt’s
catalyst. The reactions were carried out with a stoichiometric
ratio of reagents in the presence of 4x10-4 mol Pt/ mol SiH at
100°C. Processes occurred with a complete conversion of the
reagents and formation of the products 3b and 3c with 93% and
100% yields (Table 2, entries 1-2 and 4). Additionally, it was
found that an increase in the concentration of the catalyst
reduced the reaction time without affecting its selectivity (Table 2,
entry 2). Due to steric constraints in the structure of diynes 2b,
Increasing the amount of 2a from 1 up to a 10-fold excess, led to
the formation of product 3a with 86% yield (Table 1, entry 11).
The presence of products 4a and 5a was noticed in trace
amounts.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201901082
ChemCatChem
FULL PAPER
Table 1. Hydrosilylation of 1,3- diyne 2a with silsesquioxane 1.
MONOADDUCTS
BISADDUCTS
CH3
POSS=
i-Bu
O
H
POSS
Si
O
O
Si
Si
POSS
CH3
Si
O
Si
O
CH3
i-Bu
i-Bu
1
CH3
O
other
bisadducts
Si
Si
other side
+ products
7a
catalyst
CH3
O
O
O
O
H
CH3 +
+
+
H
+
POSS
POSS
Si
Si
O
O
6a
Si
Si
O
H3C
H
CH3
i-Bu
H
O
i-Bu
i-Bu
O
O
Si
Si
O
i-Bu
2a
POSS
4a
3a
5a
(i-Bu)7Si8O12
Conversion of
Si–H [%]
93
Selectivity of
3a/4a/5a/6a/7a [%]
59/3/38/0/0
48/9/43/0/0
59/11/30/0/0
76/24/0/0/0
52/5/43/0/0
57/8/35/0/0
72/4/24/0/0
53/6/41/0/0
57/13/30/0/0
58/19/23/0/0
86/5/9/0/0
Entry
Catalyst
[1]:[2a]:[Pt] [mol]
Temp.[°C]
100
Reaction time [h]
1
2
3
4
5
6
7
8
9
10
11
12
13
[Pt2(dvs)3]
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
1:
2:
10:
1:
1:
4x10−5
48
3
1
4x10−4
99
99
99
90
93
53
24
99
90
99
97
99
4x10−3
4x10−2
0.5
24
24
48
48
48
24
2
4x10−4
4x10−4 **
4x10−4
4x10−4
4x10−3
4x10-4
*
40
r.t
100
4x10−4
4x10−3
4x10−2
Pt(PPh3)4
100
40
48
24
78/5/17/0/0
83/17/0/0/0
14
15
16
17
18
19
[Pt2(dvs)3]
2:
1:
1:
1:
1:
1:
1:
2x10−4
2x10−4
2x10−3
2x10−4
2x10−4
2x10−3
100
3
99
99
99
99
99
99
19/0/81/0/0
21/0/71/8/0
16/0/69/15/0
0/0/91/9/0
0/0/94/6/0
53/0/47/0/0
2.1:
2.1:
2.3:
2.3:
2:
24
24
24
48
48
60
100
Pt(PPh3)4
Reaction conditions: mS1/Vtol.=50 mg mL−1, toluene; *mS1/Vtol.=5 mg mL−1; **after 30, 60, 90, 120 and 150 minutes 20 mg of 1 dissolved in 0.2 mL of toluene was
added. Conversions of reagents were determined by 1H NMR, the selectivity for all experiments was confirmed by 1H, 13C and 29Si NMR.
2c and silsesquioxane 1, the formation of the bisadducts was
not detected. Even when a 2-fold excess of silsesquioxane 1
was applied (Table 2, entries 3 and 5).
1,4-di(phenylboronic acid pinacol ester)-1,3-butadiyne (2f) was
investigated. It was found that the monohydrosilylation of 2e
carried out in the presence of Karstedt’s catalyst (4x10-4 mol Pt)
at 100°C was nonselective and resulted in the formation of a
mixture of products 3e/7e = 64/36 (Table 2, entry 16). On the
other hand, the reaction with 1,3-diyne 2f, which contains two
steric phenylboronic acid pinacol ester groups connected with
each C-C triple bond, performed under the same reaction
conditions led to the selective formation of monoadduct 3f (95%)
(Table 2, entry 19). An improvement in the selectivity of the
formation of monohydrosilylated product 3e was observed when
Pt(PPh3)4 was applied as a catalyst. The reaction was carried
out at 40°C for 48h (Table 2, entry 17).
The synthesis of bishydrosilylated products 5e and 5f was
performed using a ratio of 1 to 2e or 2f equal to 2:1 in the
presence of Karstedt’s catalyst at 100°C. In both reactions,
mixtures of products 3e/5e/7e and 5f/7f were formed with a
selectivity reaching 7/81/12 and 69/31 respectively (Table 2,
entries 18 and 20).
The optimization of the reaction conditions for the synthesis of
monohydrosilylated product 3d was begun with the
hydrosilylation of 2d with 1 using a stoichiometric ratio of
reagents, in the presence of Karstedt’s catalyst (4x10-4 mol
Pt/mol SiH) at 100°C (Table 2, entry 6). As a result, anti-
Markovnikow product 3d was obtained with a selectivity which
reached 86%. The application of a higher amount of the catalyst
reduced the reaction time to 30 minutes (Table 2, entry 7). It was
also found that a decrease in the reaction temperature to 40°C
did not influence the selectivity of the process (Table 2, entry 8).
Then, further tests using PtO2, Pt(PPh3)4 and Pt/SDB as the
catalysts were performed. Reactions were conducted at 40°C
and 100°C in the presence of the catalyst in the amount of 4x10-
2 – 4x10-1 mol Pt/mol SiH for 24-96 hours (Table 2, entries 9-13).
In all tests, mixtures of products 3d/7d or 3d/5d/7d were
obtained with selectivities comparable to processes carried out
in the presence of Pt2(dvs)3.
In the next stage, the monohydrosilylation of functional 1,3-
diynes: 1,4-bis(1-hydroxycyclohexyl)-1,3-butadiyne (2g), 1,6-
bis(morpholino)-2,4-hexadiyne (2h) and 10,12-docosadiyndioic
acid dimethyl ester (2i) was studied. The initial catalytic tests
were carried out with Karstedt’s catalyst (4x10-4 – 4x10-3 mol Pt)
at 100°C using an equimolar ratio of reagents (Table 2, entries
21, 23 and 25).
The synthesis of product 5d was conducted in the presence of
Karstedt’s catalyst (10-4 and 9.5x10-5 mol Pt/mol SiH) using a
molar ratio of reagents - 1: 2d = 2:1 and 2.1:1 (Table 2, entries
14,15). It was found that the selectivity of product 5d was higher
when a stoichiometric ratio of reagents was applied.
In the next part of the study, the hydrosilylation of analogs of
1,3-butadiyne 2d – 1,4-dibromophenyl-1,3-butadiyne (2e) and
The monohydrosilylation of diyne 2g allowed for the formation of
This article is protected by copyright. All rights reserved.

10.1002/cctc.201901082
ChemCatChem
FULL PAPER
Table 2. Hydrosilylation of 1,3- diynes (2b-i) with silsesquioxane 1
.
Selectivity of
3/4/5/6/7 [%]
Entry Diyne 2
1
R
Catalyst
[Pt2(dvs)3]
[Pt2(dvs)3]
[1]:[2]:[Pt]
Temp. [°C]
100
Reaction time [h]
1:1:4x10-4
1:1:2x10-3
2:1:4x10-4
1:1:4x10-4
48
2
93/7/0/0/0
93/7/0/0/0
48/2/0/0/50
100/0/0/0/0
2
b
C(CH3)3
3
48
48
4
c
C(CH3)2OSi(CH3)3
100
5
2:1:4x10-4
48
50/0/0/0/50
6
7
8
9
10
11
12
13
14
15
16
1:1:4x10-4
1:1:4x10-3
1:1:4x10-3
1:1:4x10-2
1:1:2x10-1
1:1:4x10-2
1:1:4x10-2
1:1:4x10-2
2:1:2x10-4
2.1:1: 2x10-4
1:1:4x10-4
1:1:4x10-2
2:1:2x10-4
1:1:4x10-4
2:1:2x10-4
24
0.5
48
96
48
24
24
24
85/0/5/2/8
86/0/8/0/6
84/0/5/2/9
72/0/0/0/28
81/0/2/0/17
65/0/10/0/25
85/0/2/2/11
83/0/9/0/8
100
40
[Pt2(dvs)3]
PtO2
40
d
C6H5
100
40
100
Pt(PPh3)4
Pt/SDB
8
8
4/0/82/0/14
15/0/74/5/6
64/0/0/0/36
73/0/9/3/15
7/0/81/0/12
95/0/5/0/0
0/0/69/0/31
[Pt2(dvs)3]
100
[Pt2(dvs)3]
Pt(PPh3)4
[Pt2(dvs)3]
100
40
72
48
96
48
48
17
18
19
20
e
C6H4Br-4
100
C6H4(BO2C2(CH3)4)-
4
f
[Pt2(dvs)3]
100
21
22
23
24
25
26
27
[Pt2(dvs)3]
[Pt2(dvs)3]
[Pt2(dvs)3]
[Pt2(dvs)3]
[Pt2(dvs)3]
Pt(PPh3)4
1:1:4x10-4
2:1:2x10-4
1:1:4x10-3
2:1:2x10-3
1:1:4x10-4
1:1:4x10-2
2:1:2x10-4
100
100
100
100
100
40
24
24
24
72
6
91/9/0/0/0
0/12/88/0/0
61/9/19/11/0
0/0/82/18/0
74/0/26/0/0
39/54/7/0/0
14/0/86/0/0
g
h
C6H10OH-1
CH2N(C2H4)2O
24
6
i
(CH2)8COOCH3
[Pt2(dvs)3]
100
Reaction conditions: mS1/Vtol.=50 mg mL−1, toluene; Conversions of Si-H in all reactions were complete. Conversions of reagents were determined by 1H NMR, the
selectivity for all experiments was confirmed by 1H, 13C and 29Si NMR.
monohydrosilylated products 3g/4g with a selectivity equal to
91/9 (Table 2, entry 21). Lower selectivities of the formation of
monoadduct 3 were observed in the reactions with diynes 2h
and 2i, and reached 61% and 74% respectively. In these
Conclusions
processes, mono- and bishydrosilylated products 4, 5 and 6
were formed as side products (Table 2, entries 23 and 25). The
application of Pt(PPh3)4 in the hydrosilylation of 2i with
silsesquioxane 1 was also tested. As a result, a mixture of
3i/4i/5i was formed with selectivity: 39/54/7 (Table 2, entry 26).
The bishydrosilylated products 5g-i were synthesized in
processes with a 2-fold excess of silsesquioxane 1 in the
presence of Karstedt’s catalyst. The selectivities of product 5 in
all reactions reached more than 82% (Table 2, entries 22, 24,
27). Moreover, in the process with diyne 2h, only
bishydrosilylated products 5h/6h were formed with a selectivity
reaching 82/18 (Table 2, entry 24).
A highly efficient method for the synthesis of novel functional 3-
buten-1-ynes and 1,3-butadienes with silsesquioxane moiety
was developed for the first time. The processes were based on
the hydrosilylation of 1,4-disubstituted 1,3- butadiynes (2a-i) with
silsesquioxane 1 in the presence of platinum catalysts.
It was found that the selectivity of the reaction strongly depends
on the 1,3-diyne structure. Hydrosilylation of 2,2,7,7-tetramethyl-
3,5-octadiyne
(2b),
2,2-dimethyl-7,7-bis(trimethylsilyl)-3,5-
octadiyne (2c) and 1,4-di(phenylboronic acid pinacol ester)-1,3-
butadiyne (2f) using a stoichiometric amount of reagents in the
presence of Karstedt’s catalyst led to the formation of
monohydrosilylated products 3 with a high selectivity (93% -
100%). Moreover, due to the steric hindrance in the structure of
diynes 2b, 2c and silsesquioxane 1, it was not possible to obtain
This article is protected by copyright. All rights reserved.

10.1002/cctc.201901082
ChemCatChem
FULL PAPER
For detailed data please see the ESI.†
bisadducts, even when a 2-fold excess of 1,3-diynes was
applied. The hydrosilylation of 2g constituted the exception,
because for this sterically contrained reagent the
bishydrosilylation product was also observed.
Acknowledgements
On the other hand, the monohydrosilylation of linear 2,4-
hexadiyne (2a) and less bulky diynes 2d, 2e, 2h, 2i in the
presence of Karstedt’s catalyst resulted in a mixture of mono
and bishydrosilylated products. However, in most cases, the
selectivity of the formation of the isomer 3 reached more than
86%. Lower selectivity was observed only in the reactions with
1,4-di(4-bromophenyl)-1,3-butadiyne (2e), 1,6-bis(morpholino)-
2,4-hexadiyne (2h) and 10,12-docosadiyndioic acid dimethyl
ester (2i). Moreover, in the processes with 1,3-diynes 2a and 2g,
mixtures of only monohydrosilylated products 3 and 4 were
obtained. An improvement in the selectivity of the formation of
monoadducts 3a and 3e was observed when less active
Pt(PPh3)4 was applied as a catalyst.
The authors acknowledge the financial support of the National
Science Centre in Poland by grant PRELUDIUM UMO-
2017/27/N/ST5/00224, National Centre for Research and
Development in Poland – Lider Programme no. LIDER/26/527/L-
5/13/NCBR/2014 and LIDER/6/0017/L-9/17/NCBR/2018 and
grant no. POWR.03.02.00-00-I023/17 co-financed by the
European Social Fund under the Operational Program
Knowledge Education Development.
Keywords: homogeneous catalysis, hydrosilylation,
silsesquioxane, 1,3-butadiynes functionalization.
Bisadducts were successfully synthesized through the
hydrosilylation of diynes 2a, 2d-i with silsesquioxane 1 using a
molar ratio of reagents of 2:1 in the presence of Karstedt’s
catalyst. The positive impact of the use of a non-stoichiometric
ratio of reagents on the reaction selectivity was observed only
for mono- and bishydrosilylation of 2,4-hexadiyne (2a). The
application of equimolar quantities of reagents due to the atom-
economy reaction allows for easy product separation and
reduces the total cost of the process.
The obtained products bear both double and/or triple bonds as
well as other functionalities e.g. 4-boronic acid pinacol ester, 4-
bromophenyl, hydroxyl groups, which makes them highly
desirable hybrid nano-building blocks useful for further chemical
transformations, like addition and polymerization reactions,
Suzuki–Miyaura, Sonogashira, Heck and Hiyama couplings.
References
[1] a) D.B. Cordes, P.D. Lickiss, F. Rataboul, Chem. Rev. 2010, 110, 2081-
2173; b) C. Hartmann-Thompson, Application of Polyhedral Oligomeric
Silsesquioxanes, Springer, Dordrecht, Heidelberg, London, New York,
2011.
[2] a) Q. Ye, H. Zhou, J. Xu, Chem. Asian J. 2016, 11, 1322-1337; b) S.H.
Phillips, T.S. Haddad, S.J. Tomczak, Curr. Opin. Solid State Mater. Sci.
2004, 8, 21-29; c) B.S. Ebunoluwa Ayandele, Paschalis Alexandridis,
Nanomaterials 2012, 2, 445-475.
[3] a) N.R. Vautravers, P. Andre, A.M.Z. Slawin, D.J. Cole-Hamilton, Org.
Biomol. Chem. 2009, 7, 717-724; b) F. Wang, X. Lu, C. He, J. Mater.
Chem. 2011, 21, 2775-2782; c) X.H. Yang, T. Giovenzana, B. Feild,
G.E. Jabbour, A. Sellinger, J. Mater. Chem. 2012, 22, 12689-12694; d)
Z. Li, J. Kong, F. Wang, C. He, J. Mater. Chem. C 2017, 5, 5283-5298;
e) K.L. Chan, P. Sonar, A. Sellinger, J. Mater. Chem. 2009, 19, 9103-
9120.
[4] a) F. Olivero, F. Renò, F. Carniato, M. Rizzi, M. Cannas, L. Marchese,
Dalton Trans. 2012, 41, 7467-7473; b) C. McCusker, J.B. Carroll, V.M.
Rotello, Chem. Commun. 2005, 0, 996-998; c) A.G. Kidane, G.
Burriesci, M. Edirisinghe, H. Ghanbari, P. Bonhoeffer, A.M. Seifalian,
Acta Biomaterialia 2009, 5, 2409-2417; d) R.Y. Kannan, H.J. Salacinski,
K.M. Sales, P.E. Butler, A.M. Seifalian, Cell Biochem. Biophys. 2006,
45, 129-136; e) R.Y. Kannan, H.J. Salacinski, J.-e. Ghanavi, A. Narula,
M. Odlyha, H. Peirovi, P.E. Butler, A.M. Seifalian, Plast. Reconstr. Surg.
2007, 119, 1653-1662.
Experimental Section
General procedure for the synthesis of 1,3- diynes 2c, 2e-f.
The
appropriate
terminal
alkyne
-
(1,1-dimethyl-2-
propynyl)oxy]trimethylsilane (for the synthesis of 2c), 1-bromo-4-
ethynylbenzene (for the synthesis of 2e), 4-ethynylphenylboronic acid
pinacol ester (for the synthesis of 2f) (2 mmol) and CuCl (0.4 mmol) were
dissolved in 20 mL of toluene. Subsequently, 0.2 mmol of piperidine was
added to the solution. The reaction was carried out for 24 hours at 80°C.
After that time, the solvent was evaporated. The crude product was
dissolved in n-hexane and filtered through Celite. For the product 2e,
simple filtration was applied using a syringe filter (pore size – 0.2 µm)
directly after the reaction. The products were characterized by 1H, 13C,
29Si NMR spectroscopy, and GC MS.
[5] a) Y. Itami, B. Marciniec, M. Kubicki, Chem. Eur. J. 2004, 10, 1239-1248; b)
P. Żak, C. Pietraszuk, B. Marciniec, G. Spólnik, W. Danikiewicz, Adv.
Synth. Cat. 2009, 351, 2675-2682; c) J. Waehner, B. Marciniec, P.
Pawluć, Eur. J. Inorg. Chem. 2007, 2007, 2975-2980.
[6] a) G. Cheng, N.R. Vautravers, R.E. Morris, D.J. Cole-Hamilton, Org.
Biomol. Chem. 2008, 6, 4662-4667; b) Y. Liu, W. Yang, H. Liu,
Chemistry 2015, 21, 4731-4738; c) A. Sellinger, R. Tamaki, R.M. Laine,
K. Ueno, H. Tanabe, E. Williams, G.E. Jabbour, Chem. Commun. 2005,
3700-3702.
General procedure for the hydrosilylation of 1,3-diynes (2a-i) with
silsesquioxane 1.
[7] F.J. Feher, K.J. Weller, J.J. Schwab, Organometallics 1995, 14, 2009-2017.
[8] a) B. Marciniec, H. Maciejewski, C. Pietraszuk, P. Pawluć in
Hydrosilylation: A Comprehensive Review on Recent Advances (Ed.: B.
Marciniec), Springer, 2009; b) A. Sellinger, R.M. Laine,
Macromolecules 1996, 29, 2327-2330; c) M.S. Soh, A.U.J. Yap, A.
Sellinger, Eur. Polym. J. 2007, 43, 315-327; d) X. Su, H. Xu, Y. Deng, J.
Li, W. Zhang, P. Wang, Mater. Lett. 2008, 62, 3818-3820; e) K. Xiang,
L. He, Y. Li, C. Xu, S. Li, RSC Adv. 2015, 5, 97224-97230; f) C. Zhang,
R.M. Laine, J. Am. Chem. Soc. 2000, 122, 6979-6988; g) N. Auner, J.W.
Bats, D.E. Katsoulis, M. Suto, R.E. Tecklenburg, G.A. Zank, Chem.
Mater. 2000, 12, 3402-3418; h) B. Marciniec, Comprehensive
Handbook on Hydrosilylation, Pergamon Press, 1992; i) J. Sun, L.
Deng, ACS Catal. 2016, 6, 290-300; j) A.K. Roy in Advances in
To a solution of silsesquioxane 1 (0.1 g, 0.11 mmol) and an appropriate
1,3 - diyne (2a-i) (0.055 or 0.11 mmol) in toluene platinum catalyst -
[Pt2(dvs)3], Pt(PPh3)4 , PtO2 or Pt/SDB was added in an amount varying
from 10−5 to 10−2 mol of Pt, depending on the experiment. Subsequently,
the reaction mixture was heated to 40°C -100°C or maintained at room
temperature and stirred until a full conversion of Si-H was detected by 1H
NMR. Then the solvent was evaporated under vacuum. The crude
products were dissolved in n-hexane and filtered through silica gel,
excluding products 3-7 c, f-i. For these products, filtration through Celite
was applied. The isolated products were characterized by 1H, 13C, and
29Si NMR, MALDI TOF.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201901082
ChemCatChem
FULL PAPER
Organometallic Chemistry (Eds.: R. West, A.F. Hill, M.J. Fink),
[10] a) A. Franczyk, K. Stefanowska, M. Dutkiewicz, D. Frąckowiak, B.
Marciniec, Dalton Trans. 2017, 46, 158-164; b) M. Walczak, K.
Stefanowska, A. Franczyk, J. Walkowiak, A. Wawrzyńczak, B.
Marciniec, J. Catal. 2018, 367, 1-6; c) K. Stefanowska, A. Franczyk, J.
Szyling, M. Pyziak, P. Pawluć, J. Walkowiak, Chem. Asian J. 2018, 13,
2101-2108.
Academic Press, 2007, pp. 1-59; k) B.M. Trost, Z.T. Ball, Synth. 2005,
2005, 853-887; l) B. Marciniec in Applied Homogeneous Catalysis with
Organometallic Compounds (Eds.: B.Cornils, W.A. Herrmann), Wiley
1996, pp. 487-506; m) I. Ojima in Organic Silicon Compounds (Eds.:
Z.R. Saul Patai), Wiley, Chichester, 1989, pp. 1479-1526.
[9] a) J. Chen, J. Guo, Z. Lu, Chin. J. Chem. 2018, 36, 1075-1109; b) J. Guo,
Z. Lu, Angew. Chem. Int. Ed. 2016, 55, 10835-10838; c) J. Guo, H.
Wang, S. Xing, X. Hong, Z. Lu, Chem 2019, 5, 881-895. d) Z. Cheng, S.
Xiang, J. Guo, B. Cheng, L-F. Hu, X-H. Zhang, Z. Lu, Chin. J. Chem.
2019, 37, 457-461. e) H. Wen, G. Liu, Z. Huang, Coord. Chem. Rev.
2019, 386, 138-153. f) Y-B. Zhou, Z-K. Liu, X-Y. Fan, R-H. Li, G-L.
Zhang, L. Chen, Y-M. Pan, H-T. Tang, J-H. Zeng, Z-P. Zhan, Org. Lett.
2018, 20, 7748-7752.
[11] J. Walkowiak, K. Salamon, A. Franczyk, K. Stefanowska, J. Szyling, I.
Kownacki, J. Org. Chem. 2019, 84, 2358-2365.
[12] a) A. Tillack, S. Pulst, W. Baumann, H. Baudisch, K. Kortus, U. Rosenthal,
J. Organomet. Chem. 1997, 532, 117-123; b) A. Tillack, D. Michalik, C.
Koy, M. Michalik, Tetrahedron Lett. 1999, 40, 6567-6568; c) R.J. Perry,
M. Karageorgis, J. Hensler, Macromol. 2007, 40, 3929-3938; d) F.
Alonso, R. Buitrago, Y. Moglie, A. Sepúlveda-Escribano, M. Yus,
Organomet. 2012, 31, 2336-2342.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201901082
ChemCatChem
FULL PAPER
Entry for the Table of Contents (Please choose one layout)
Layout 1:
FULL PAPER
Text for Table of Contents
Author(s), Corresponding Author(s)*
Page No. – Page No.
Title
((Insert TOC Graphic here: max.
width: 5.5 cm; max. height: 5.0 cm))
Layout 2:
FULL PAPER
K. Stefanowska, A. Franczyk*, J.
Szyling, J. Walkowiak*
Page No. – Page No.
Synthesis of functional 3-buten-1-
ynes and 1,3-butadienes with
silsesquioxane moiety via the
hydrosilylation of 1,3-diynes
The first general procedure for the catalytic mono- and/or bishydrosilylation of 1,3-
diynes with silsesquioxane has been developed. The obtained with high yields
products: 3-buten-1-ynes and 1,3-butadienes with silsesquioxane moiety are
characterized by unique structures and potential applications.
This article is protected by copyright. All rights reserved.