Regio- and chemoselective coupling of polyalkynes: A convenient access to polyarylacetylenes and polyenynes

Article abstract of DOI:10.1002/ejoc.200500001

Mono- or disilylated α,ω-diynes and disilylated triynes can be regioselectively homologated at each acetylenic end, silylated or not, by two and three, respectively, successive Pd/ Ag-catalyzed coupling reactions. Each coupling being selective either for

Full text of DOI:10.1002/ejoc.200500001

FULL PAPER
Regio- and Chemoselective Coupling of Polyalkynes: A Convenient Access to
Polyarylacetylenes and Polyenynes
Ulla Halbes-Létinois,[a] Aleksander Vasiliev,[a,b] and Patrick Pale*[a]
Keywords: Cross-coupling / Palladium / Silver / Alkynes / Molecular devices
Mono- or disilylated α,ω-diynes and disilylated triynes can
be regioselectively homologated at each acetylenic end, si-
lylated or not, by two and three, respectively, successive Pd/
Ag-catalyzed coupling reactions. Each coupling being selec-
tive either for terminal alkyne, trimethylsilylalkyne or for tri-
alkylsilylalkyne, the combination of these coupling methods
offers a unique and rapid access to polyunsaturated com-
pounds.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2005)
indeed able to successively and selectively couple each acet-
ylenic end.
Introduction
The rapid construction of polyunsaturated systems is of
prime importance for material science[1] and to a less extend
for natural products chemistry.[2] The elaboration of regular
arrays of triple and double bonds is indeed often required
as core or building blocks for organic materials, especially
for molecular electronics,[1,3] nonlinear optic applica-
tions[1,4] and organic crystals assemblies.[5] Such building
blocks are often obtained through cross-coupling reactions.
However, nonsymmetrical structures cannot easily be ob-
tained through classical methods, and their constructions
usually require multi-step sequences involving protection–
deprotection steps.[1–5] Avoiding such tedious steps would
be interesting. Moreover, building up molecules over di- or
tritopic compounds from either side in a controlled manner
would be an interesting and efficient way towards organic
crystals or organic-based materials, especially electronic de-
vices.
Based on mechanistic considerations and on solving syn-
thetic problems related to enediyne antibiotics,[6,7] we devel-
oped several new methods for the synthesis of conjugated
enynes. These methods rely on the coupling of vinyl triflates
with either free alkynes,[7] 1-(trimethylsilyl)alkynes[8] or 1-
(trialkylsilyl)alkynes.[9] Here we demonstrated that these
coupling methods are in fact orthogonal, each one being
selective for one kind of alkynes. Thus, each kind of acetyle-
nic end could be selectively elongated by one of our specifi-
cally designed cross-coupling reactions, enabling for the ori-
ented construction of polytopic enyne or arylyne systems
(Figure 1). Applied to polyacetylenic compounds protected
or not by trimethylsilyl and/or trialkylsilyl groups, we were
Figure 1. The different arrows indicate that each kind of acetylenic
end could be independently elongated through a specific cross-
coupling reaction.
Results and Discussion
The oriented synthesis of ditopic arylynes or enynes can
be achieved through two routes including each two steps.
The first approach is based on two successive coupling reac-
tions onto 1-silylated 1,ω-diynes. The latter can easily be
coupled at their free acetylenic end with different aryl or
vinyl triflates or halides using various Sonogashira coupling
conditions,[10] including ours (Scheme 1).[7–9]
[a] Laboratoire de synthèse et réactivité organique, associé au
CNRS, Institut Le Bel, Université L. Pasteur,
4 rue B. Pascal, 67000 Strasbourg, France
[b] On leave from the Laboratory of Organic Chemistry, St. Peters-
burg State Forest Technical Academy,
per. 5, St. Petersburg 194021, Russia
2828
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
DOI: 10.1002/ejoc.200500001
Eur. J. Org. Chem. 2005, 2828–2834

Convenient Access to Polyarylacetylenes and Polyenynes
FULL PAPER
found that the so obtained (trimethylsilyl)acetylenes 1 can
then be directly homologated with either aryl iodides or vi-
nyl triflates (Table 1).
Two set of conditions could be used for converting 1 to
the corresponding bis(enynes) 3: The promoter required to
initiate the Pd/Ag-catalyzed coupling reaction could be
either the commercially available salt tetrabutylammonium
fluoride trihydrate[9] or a combination of carbonate salt and
methanol.[8] Typical examples are provided by the coupling
of 1a and 1c. Compound 1a smoothly reacted with the vinyl
triflate 2b, yielding the expected 1,4-bis(enynyl)benzene de-
rivative 3a whatever the conditions used (Table 1, Entries
1–2). However, the product was quite sensitive and decom-
Scheme 1.
For example, compounds 1a–c have been obtained by posed under both conditions, but nevertheless, it could be
coupling 1-ethynyl-4-(trimethylsilylethynyl)benzene with the isolated in reasonable yields. Compound 1c was conve-
vinyl triflates derived from 4-tert-butylcyclohexene (2a)[11] niently converted into the highly conjugated aryl enediynes
or dimedone (2b)[12] or with phenyl iodide (Scheme 2).
3b–c in good yields through coupling with the vinyl triflate
Instead of deprotecting the untouched silylated acetyle- 2a or the triflate derived from tetralone (2c)[13] (Table 1, En-
nic end and performing another coupling reaction, we tries 3, 4 and 5, 6, respectively).
Scheme 2.
Table 1. Yields given for pure isolated products; a) TBAF = nBu4NF·3H2O; b) conditions: nBu4NF·3H2O 1.5 equiv., AgI 0.2 equiv.,
[Pd(PPh3)4] 0.1 equiv., DMF, room temp.; c) conditions: K2CO3 4 equiv., MeOH 4 equiv., AgCl 0.2 equiv., [Pd(PPh3)4] 0.1 equiv., DMF,
room temp.
Eur. J. Org. Chem. 2005, 2828–2834
www.eurjoc.org
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2829

U. Halbes-Létinois, A. Vasiliev, P. Pale
FULL PAPER
In the second and more innovative approach, bis(acetyl- It is worth to note that 3a–c have also been prepared start-
enic) compounds bearing two different kinds of silyl groups ing from the corresponding 1-trimethylsilyl-1,ω-diyne (see
at their acetylenic ends, e.g. 4, could be specifically coupled Table 1, Table 2). The same compound can thus be ob-
at one end using the appropriate coupling method. Indeed, tained through different sequences of coupling using the ap-
the
1-(triisopropylsilyl)ethynyl-4-[(trimethylsilyl)ethynyl]- propriate method at each step. Whatever the route, only two
benzene (4a)[14] or its aliphatic analog 4b can thus be di- steps suffice to get compounds, which can be used as mol-
rectly coupled at their TMS ends using the potassium car- ecular wired, organic diodes or NLO devices.[1–4]
bonate–methanol method[8] (Table 2). With different vinyl
To demonstrate further the usefulness of our methods,
triflates, the expected enynes 5a–b, 5d–e were always ob- and as a step toward organic transistors, we prepared a tri-
tained very cleanly and in excellent yields (Entries 1–2, 5,6). topic triyne, and we selectively elongated it at each acetyle-
However, with aryl iodides, these coupling conditions nic end by coupling reactions.
proved to be less efficient and for example, 5c was obtained
The disilylated triyne 6 was obtained by successive oxi-
in around 50% (Entry 3). A screening of bases showed that dation and alkynylation starting from the readily available
the coupling efficiency could be restored by replacing po- 3-(triisopropylsilyl)propynol (Scheme 3).[16]
tassium carbonate by cesium carbonate (Entry 4 vs. 3),
yielding 5c with 83%.
The so obtained 1-triisopropylsilyl acetylenic derivatives
5 could then be directly homologated at their triisopropyl-
silyl end using the TBAF coupling method[9] (Table 3). In
these conditions, the 1-(triisopropylsilyl)ethynyl-4-(phenyle-
thynyl)benzene (5c) reacted quantitatively with the para-ni-
trophenyl iodide yielding the highly conjugated polyarylace-
tylenic derivative 3d[15] (Entry 1). 5c also reacted very ef-
ficiently with various vinyl triflates such as 2a and 2c giving
the corresponding arylenynes 3b–c, respectively, in excellent
yields (Entry 2 and 3 respectively).
To illustrate the versatility of the methods, 3c was also
prepared from 5a by coupling with phenyl iodide (Entry 4). Scheme 3.
Table 2. Yields given for pure isolated products; conditions: K2CO3 4 equiv., MeOH 4 equiv., AgCl 0.2 equiv., Pd(PPh3)4 0.1 equiv.,
DMF, room temp., except for Entry 4 where K2CO3 was replaced by Cs2CO3.
2830
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
Eur. J. Org. Chem. 2005, 2828–2834

Convenient Access to Polyarylacetylenes and Polyenynes
FULL PAPER
Table 3. Yields given for pure isolated products; conditions: nBu4NF·3H2O 1.5 equiv., AgI 0.2 equiv., Pd(PPh3)4 0.1 equiv., DMF, room
temp.
Compound 6 was engaged in a coupling reaction with 18.5 ppm, 84.5 and 104.6 ppm). This remaining acetylenic
2a using DIPEA as a base and [Pd(PPh3)4] and AgCl as unit was then directly substituted by a phenyl group
catalysts.[7] The expected enetriyne 7 was cleanly obtained through coupling using our TBAF method,[9] providing the
in good isolated yield. The TMS and TIPS ethynyl groups differentiated trienyne 9 in good overall yield (Scheme 4).
remained unaffected as shown by their typical signals in the
In conclusion, we have demonstrated that mono- or di-
1H and 13C NMR spectra of 7 (δ = 0.18 and –0.48 ppm for silylated diynes and disilylated triynes can be regioselec-
TMS; 1.08, 11.2 and 18.5 ppm for TIPS). Using the potas- tively homologated at each acetylenic end by respectively
sium carbonate–methanol coupling method,[8] 7 was then two and three successive Pd/Ag-catalyzed coupling reac-
specifically coupled at its trimethylsilyl acetylenic end, fur- tions using the appropriate conditions. The combination of
1
nishing 8 in good yield. This compound exhibited in its H these coupling methods offers thus a unique and rapid ac-
NMR spectrum the characteristic signal of the enyne moie- cess to polyunsaturated compounds, which could be used
ties (δ = 6.05 and 6.52 ppm) and the set of signals typical as molecular electronic devices. Further works toward such
of the triisopropylsilyl acetylenic unit (δ = 11.2 and devices are now in progress.
Scheme 4.
Eur. J. Org. Chem. 2005, 2828–2834
www.eurjoc.org
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2831

U. Halbes-Létinois, A. Vasiliev, P. Pale
FULL PAPER
anol was added through a microsyringe. The mixture was stirred
for five minutes in the dark and the alkyne (1.1 equiv.), dissolved
in 2 mL of DMF was added through a syringe. Once the starting
material had disappeared as judged by TLC, diethyl ether (10 mL)
was added, followed by 10 mL of water. The mixture was filtered
through Celite and the phases were separated. The aqueous layer
was extracted three times with diethylether, the combined organic
layers were washed three times with water to remove DMF. The
organic phase was dried with MgSO4, filtered and concentrated in
vacuo. The crude product was passed over a silica gel column to
give the pure product.
Experimental Section
General: All experiments have been carried out under inert gas.
Common reagents and materials were purchased from commercial
sources. Thin layer chromatography has been performed on silica
gel from Merck, Art. 7748 Kieselgel 60 PF254. The column
chromatography has been carried out with Merck Art. 9385 Kiesel-
gel 60 (0.04–0.06). The solvents used for the column chromatog-
raphy have been distilled before use. The NMR spectra were re-
corded with a Bruker Avance 300 spectrometer, with working fre-
1
quencies of 300 MHz for H and 75.43 MHz for 13C NMR spec-
troscopy. Chemical shifts δ are expressed relative to internal TMS
Pd/Ag-Catalyzed Coupling of 1-(Trialkylsilyl)alkynes: The vinyl
triflate (0.5 mmol) was dissolved in 10 mL anhydrous and degassed
DMF under argon. [Pd(PPh3)4] (0.1 equiv.) and AgCl (0.2 equiv.)
were added. The trialkylsilyl alkyne (1.1 equiv.) was dissolved in
2 mL of DMF and added through a syringe. Then, TBAF was dis-
solved in 5 mL DMF and added to the reaction mixture. The mix-
ture was stirred in the dark until the starting material had disap-
peared according to TLC. Diethyl ether (10 mL) was added, fol-
lowed by 10 mL of water. The mixture was filtered through Celite
and the phases were separated. The aqueous layer was extracted
three times with diethyl ether, the combined organic layers were
washed three times with water to remove the DMF. The organic
phase was dried with MgSO4, filtered and concentrated in vacuo.
The crude product was purified over a silica gel column to give the
pure product.
1
for H NMR spectra, 13C NMR spectra are referenced to CDCl3
(δ = 77.0 ppm). The coupling constants J are given in Hz. The
multiplets have been indicated by the following abbreviations: s
(singlet), d (doublet), t (triplet), q (quadruplet), dd (doublet of
doublets), m (multiplet). The infrared spectra were recorded with
Fourier Transform Spectrafile IRTM Plus as film on NaCl slides or
as KBr pellets, ν is given in cm–1. Mass spectra have been recorded
˜
with a Fisons Autospec apparatus using positive FAB ionisation.
Elementary analysis were realised by the elementary analysis ser-
vice at the Université Louis Pasteur, Strasbourg I.
A: Vinyl Triflates: 4-tert-Butylcyclo-1-hexenyl Trifluoromethane-
sulfonate (2a), 4,4-dimethyl-3-oxocyclohex-1-enyl trifluorome-
thanesulfonate (2b) and 3,4-dihydronaphtalen-1-yl triflurome-
thanesulfonate (2c) have been prepared according to ref.[11–13]
.
B: Starting Diynes: 1-(Triisopropylethynyl)-4-(trimethylsilylethyn-
yl)benzene (4a) has been obtained according to ref.[11]
1-(4-tert-Butylcyclohexenyl)ethynyl-4-(trimethylsilylethynyl)benzene
(1a): M.p. 118–120 °C. 1H NMR (CDCl3): δ = 0.25 (s, 9 H, TMS),
0.87 (s, 9 H, tBu), 1.05–1.32 (m, 2 H, H3,5), 1.76–1.91 (m, 2 H,
H3,6), 2.04–2.15 (m, 3 H, H4,6), 5.98 (m, 1 H, H2), 7,31–7,35 (m,
4 H, Har) ppm. 13C NMR (CDCl3): δ = 0.0 (TMS), 22.4 (C5), 27.2
(tBu), 27.6 (C3), 30.9 (C6), 32.2 (tBu), 43.3 (C4), 86.3 (CϵC–Si),
89.1 (CϵC–Ar), 92.3 (CϵC), 104.6 (CϵC–Si), 120.45 (C1), 123.1,
123.9, 131.3, 131.9 (Car), 136.2 (C2) ppm. MS: m/z = 334 [M+], 270,
255, 225, 120, 73, 57. HRMS (C23H30Si): found 334.2071, calcd.
334.2116.
.
1-(Triisopropylsilyl)-8-(trimethylsilyl)octa-1,7-diyne (4b): 1-Trimeth-
ylsilyl-1,7-octadiyne[17] (1.78 g, 10 mmol) was dissolved in THF
and cooled to –78 °C. Butyllithium (1.25 m soln. in hexane,
0.76 mL, 0.95 equiv.) was slowly added via syringe. The solution
was stirred for ten minutes and then TIPSCl (1.92 g, 1 equiv.) was
added. The mixture was warmed to room temperature. An aqueous
solution of NH4Cl was added and the phases were separated. The
aqueous layer was extracted three times with diethyl ether and the
combined organic phases are dried with MgSO4. After evaporation
of the solvents, the crude product purified via column chromatog-
raphy (pentane 100%). 1H NMR (CDCl3): δ = 0.07 (s, 9 H, TMS),
1.00 (s, 21 H, TIPS), 1.54 (m, 4 H, H4,5), 2.19 (t, J = 3.7 Hz, 4 H,
H3,6) ppm. 13C NMR (CDCl3): δ = 0.06 (TMS), 15.2 (TIPS), 18.6
(TIPS), 19.3 (C3, 6), 27.5 (C4), 27.6 (C5), 80.4 (C1), 84.6 (C8),
107.0 (C7), 108.5 (C2) ppm.C20H38Si2 (343.68): calcd. C 71.77, H
11.44; found C 71.79, H 11.50.
1-(4,4-Dimethyl-3-oxocyclohex-1-enylethynyl)-4-(trimethylsilyl-
1
ethynyl)benzene (1b): H NMR (300 MHz, CDCl3): δ = 0.25 (s, 9
H, TMS), 1.08 (s, 6 H, Me), 2.28 (s, 2 H, H6), 2.41 (d, J = 1.4 Hz,
2 H, H4), 6.28 (t, J = 1.4 Hz, 1 H, H2), 7.40–7.47 (m, 4 H, Har)
ppm. 13C NMR (CDCl3): δ = 0.03 (TMS), 28.1 (Me), 32.2 (C5),
43.2 (C6), 51.1 (C4), 89.6 (CϵC–Si), 90.1 (CϵC–C1), 99.1 (CϵC–
C1), 104.6 (CϵC–Si), 121.0, 125.0 (Car), 131.4 (C2), 131.4, 131.8
(Car), 141.0 (C1), 198.9 (C3) ppm. MS: m/z = 320 (85) [M+], 305
(100), 264, (14), 249 (22). HRMS (C21H24OSi): calcd. 320.5002,
found 320.4987.
C: General Procedure for the Successive Pd/Ag-Catalyzed Coupling
Reactions. Pd/Ag-Catalyzed Coupling of Terminal Alkynes: The vi-
nyl triflate (0.5 mmol) was dissolved in 10 mL anhydrous and de-
gassed DMF under argon. [Pd(PPh3)4] (0.1 equiv.) and AgCl (0.2
equiv.) were added, followed by DIPEA (1.2 equiv.). The mixture
was stirred for five minutes and the alkyne, dissolved in 2 mL of
DMF (1.1 equiv.) was added through a syringe. Once the starting
material had disappeared as judged by TLC, of diethyl ether
(10 mL) was added, followed by 10 mL of water. The mixture was
filtered through Celite. The aqueous layer was extracted three times
with ether, the combined organic layers were washed three times
with water to remove DMF. The organic phase was then dried with
MgSO4, filtered and concentrated in vacuo. The crude product was
purified over a silica gel column to give the pure product.
1-[(4-tert-Butylcyclohexenyl)ethynyl]-4-(4,4-dimethyl-3-oxohex-1-en-
ylethynyl)benzene (3a): M.p. 132–134 °C. 1H NMR (300 MHz,
CDCl3): δ = 0.87 (s, 9 H, tBu), 1.08 (s, 6 H, Me), 1.15–1.29 (m, 2
H, H4,6), 1.83–1.95 (m, 2 H, H3,6), 2.15–2.27 (m, 3 H, H3,5), 2.28
(s, 2 H, H6Ј), 2.41 (d, J = 1.4 Hz, 2 H, H4Ј), 6.23 (m, J = 2.3 Hz,
1 H, H2), 6.28 (t, J = 1.4 Hz, 1 H, H2Ј), 7.39 (s, 4 H, Har) ppm.
13C NMR (CDCl3): δ = 22.3 (C5), 27.6 (tBu), 28.0 (C3), 28.1 (Me),
30.6 (C6), 32.2 (C5Ј), 33.8 (tBu), 43.2 (C6Ј), 44.3 (C4), 51.1 (C4Ј),
86.6 (CϵC–C1), 90.1 (CϵC–C1Ј), 93.8 (CϵC–C1), 99.1 (CϵC–
C1Ј), 120.3 (C1), 121.0, 125.0, 131.4 (C2Ј), 131.4, 131.8, 136.5 (C2),
141.0 (C1Ј), 198.9 (C3Ј) ppm. MS: m/z = 384.245 [M+]. C28H32O
(384.55): calcd. C 87.45, H 8.39, O 4.16; found C 87.99, H 8.25, O
3.95.
Pd/Ag-Catalyzed Coupling of 1-(Trimethylsilyl)alkynes: The vinyl
triflate (0.5 mmol) was dissolved in 10 mL anhydrous and degassed
DMF under argon. [Pd(PPh3)4] (0.1 equiv.) was added and then
AgCl (0.2 equiv.). K2CO3 (4 equiv.) was added as a solid and meth-
1-[(4-tert-Butylcyclohexenyl)ethynyl]-4-(phenylethynyl)benzene (3b):
M.p. 128–130.5 °C. 1H NMR (300 MHz, CDCl3): δ = 0.88 (s, 9 H,
tBu), 1.14–1.30 (m, 2 H, H3,5), 1.83–1.95 (m, 2 H, H3,6), 2.14–
2832
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
Eur. J. Org. Chem. 2005, 2828–2834

Convenient Access to Polyarylacetylenes and Polyenynes
FULL PAPER
2.28 (m, 3 H, H4,6), 6.22 (m, J = 2.4 Hz, 1 H, H2), 7.32–7.35 (m,
(C5), 23.5 (C4), 27.2 (C3Ј), 31.0 (C4Ј), 78.3 (CϵC–C), 84.1 (CϵC–
3 H, Har), 7.38 (d, J = 8.4 Hz, 2 H), 7.44 (d, J = 8.4 Hz, 2 H, Har), Si), 91.1 (CϵC–C), 108.7 (CϵC–Si), 125.0 (Car), 126.4 (C1Ј), 127.2,
7.49–7.53 (m, 2 H, Har) ppm. 13C NMR (CDCl3): δ = 23.79(C5), 127.3 (Car), 133.2 (C2Ј), 133.8 (Car), 135.1 (Car) ppm. C27H38Si
27.12 (tBu), 27.58 (C3), 30.67 (C6), 32.20 (tBu), 43.20 (C4),
86.81(CϵC–C), 89.22 (CϵC–C), 90.92 (CϵC–Ar), 92.97 (CϵC–
Ar), 120.41 (C1), 122.46, 123.11, 123.68, 128.36, 131.34, 131.42,
131.59 (Car), 136.04 (C2) ppm. MS: m/z = 338 (100) [M+], 295 (7),
281 (14), 254 (44), 215 (6), 189 (3). C26H26 (338.48): calcd. C 92.0,
H 7.85; found C 92.26, H 7.74.
(390.67): calcd. C 83.01, H 9.80; found C 82.90 H 9.81.
3-Ethynyl-1-(triisopropylsilyl)-5-(trimethylsilyl)penta-1,4-diyn-3-ol
1
(6): H NMR: δ = 0.19 (s, 9 H, TMS), 1.07 (s, 21 H, TIPS), 2.16
(s, 1 H, H7), 2.63 (s, 1 H, OH). 13C NMR: δ = –0.57 (TMS), 11.2
(TIPS), 18.5 (TIPS), 54.2 (C3), 71.0 (C7), 81.2 (C6), 85.5 (C1), 88.1
(C5), 101.3 (C4), 103.6 (C2) ppm. FAB-MS: m/z (%) = 395.2 (100)
[M + Na+], 355,2 (15), 315 (15). C19H32OSi2 (332.63) calcd. C
68.01, H 9.70, O 4.81; found: C 68.25, H 9.81, O 4.90.
1-(3,4-Dihydronaphthylethynyl)-4-(phenylethynyl)benzene (3c): 1H
NMR (CDCl3): δ = 2.36 (dt, J = 4.8, J = 8.1, 2 H, H3), 2.77 (t, J
= 8.1, 2 H, H4), 6.50 (d, J = 4.8, 1 H, H2), 7.00–7.64 (m, 9 H,
Har), 7.28 (d, J = 9.3, 2 H, Har), 7.45 (d, J = 9.3, 2 H, Har) ppm.
13C (CDCl3): δ = 22.8 (C3), 27.1 (C4), 89.0, 89.2, 90.0, 91.1(CϵC),
122.3 (Car), 122.9 (C3Ј), 125.0 (C1Ј), 125.6, 126.1, 126.7, 127.5,
127.8, 128.1, 128.4, 131.51, 132.4, 134.2 (Car), 136.0 (C2), 137.46
(Car) ppm. C30H30 (390.56): calcd. C 94.51, H 5.49; found C 94.77,
H 5.55.
3-[(tert-Butylcyclohex-1-enyl)ethynyl]-1-(triisopropylsilyl)-5-(tri-
methylsilyl)penta-1,4-diyn-3-ol (7): 1H NMR: δ = 0.18 (s, 9 H,
TMS), 0.85 (s, 9 H, H8Ј), 1.08 (s, 21 H, TIPS), 1.18–1.23 (m, 3 H,
H4Ј, 6Ј), 1.72–1.92 (m, 2 H, H3Ј,6Ј), 2.15–2.26 (m, 3 H, H3Ј,5Ј),
2.80 (s, 1 H, OH), 6.05 (t, 1 H, H2Ј) ppm. 13C NMR: δ = –0.48
(TMS), 11.2 (TIPS), 18.5 (TIPS), 23.6 (C6Ј), 27.0 (C8Ј), 27.4 (C3Ј),
30.3 (C5Ј), 32.1 (C7Ј), 43.1 (C4Ј), 55.0 (C3), 65.8, 84.2 (C1), 84.3,
87.4 (C5), 102.1 (C4), 104.6 (C2), 119.3 (C1Ј), 137.4 (C2Ј) ppm.
FAB-MS: m/z (%) = 470.2 (20) [M+], 442 (85), 355 (100).
1-(3,4-Dihydronaphthyl)ethynyl-4-(triisopropylsilylethynyl)benzene
1
(5a): H (CDCl3): δ = 1.05 (s, 21 H, TIPS), 2.76 (t, J = 8.11 Hz, 2
H, H4), 2.36 (dt, J = 4.8, J = 8.1 Hz, 2 H, H3), 6.50 (t, J = 4.8 Hz,
1 H, H2), 7.28 (d, J = 9.3 Hz, 2 H, H3,5), 7.45 (d, J = 9.3 Hz, 2
H, H2,6), 7.00–7.25 (m, 4 H, H6, 7, 8, 9). 13C NMR (CDCl3): δ =
11.3 (TIPS), 18.7 (TIPS), 27.1 (C3), 40.8 (C4), 88.8 (CϵC–Si), 89.7
(CϵC–C), 92.3 (CϵC–C), 106.3 (CϵC–Si), 122.0 (Car), 125.0 (C1),
126.6, 126.7, 127.4, 127.6(Car), 131.3 (C2), 131.7, 134.3, 136.0,
137.9, 150.3 (Car) ppm. C29H34Si (410.67): calcd. C 84.82, H 8.34;
found C 84.55, H: 8.40.
3-[(tert-Butylcyclohex-1-enyl)ethynyl]-5-(3,4-dihydronaphthyl)-1-(tri-
isopropylsilyl)penta-1,4-diyn-3-ol (8): 1H NMR: δ = 0.86 (s, 9 H,
H8Ј), 1.08 (s, 21 H, TIPS), 1.18–1.23 (m, 3 H, H4Ј,6Ј), 1.25 (s, 1
H, OH), 1.72–1.92 (m, 2 H, H3Ј,6Ј), 2.15–2.26 (m, 3 H, H3Ј,5Ј),
2.37 (m, 2 H, H3ЈЈ), 2.79 (t, J = 7.9 Hz, 2 H, H4ЈЈ), 6.05 (m, 1 H,
H2Ј), 6.52 (t, 1 H, J = 4.8 Hz, H2ЈЈ), 7.08–7.28 (m, 3 H, Har), 7.58
(d, J = 7.2 Hz, 1 H, Har) ppm. 13C NMR: δ = 11.2 (TIPS), 18.6
(TIPS), 23.6 (C6Ј), 26.9 (C8Ј), 27.1 (C3ЈЈ), 27.4 (C8Ј), 29.7 (C3Ј),
30.1 (C5Ј), 30.3 (C4ЈЈ), 32.2 (C7Ј), 43.1 (C4Ј), 55.0 (C3), 72.3 (C5),
84.5 (C1), 88.0 (C4), 104.6 (C2), 119.3 (C1Ј), 125.1 (C1ЈЈ), 125.5,
126.6, 127.3, 127.7, 132.3(Car), 134.8 (C2ЈЈ), 137.1(Car), 137.4 (C2Ј)
1-(4-tert-Butylcyclohexenylethynyl)-4-(triisopropylethynyl)benzene
1
(5b): M.p. 118–120 °C. H NMR (CDCl3): δ = 0.87 (s, 9 H, tBu),
1.11 (s, 21 H, TIPS), 1.05–1.32 (m, 2 H, H3,5), 1.76–1.91 (m, 2 H,
H3,6), 2.04–2.15 (m, 3 H, H4,6), 5.98 (m, 1 H, H2) ppm. 13C NMR
(CDCl3): δ = 11.3 (TIPS), 18.5 (TIPS), 22.4 (C5), 27.2 (tBu), 27.6
(C3), 30.9 (C6), 32.2 (tBu), 43.3 (C4), 88.3 (CϵC–Si), 89.1 (CϵC–
Ar), 92.3 (CϵC), 106.2 (CϵC–Si), 120.45 (C1), 123.1, 123.9, 131.3,
131.9 (Car), 136.2 (C2) ppm. MS: m/z = 418.311 [M+], C29H42Si
(418.31): calcd. C 83.18, H 10.11; found C 82.85, H 10.15.
ppm. FAB-MS: m/z (%) = 547 (45) [M + Na+], 507 (100) [M+
–
OH], 165 (100).
3-[(tert-Butylcyclohex-1-enyl)ethynyl]-5-(3,4-dihydronaphthyl)-1-
phenylpenta-1,4-diyn-3-ol (9): 1H NMR: δ = 0.86 (s, 9 H, H8Ј), 1.08
(s, 21 H, TIPS), 1.18–1.23 (m, 3 H, H4Ј,6Ј), 1.25 (s, 1 H, OH),
1.72–1.92 (m, 2 H, H3Ј,6Ј), 2.15–2.26 (m, 3 H, H3Ј, 5Ј), 2.37 (m, 2
H, H3ЈЈ), 2.79 (t, J = 7.9 Hz, 2 H, H4ЈЈ), 6.05 (m, 1 H, H2Ј), 6.52
(t, J = 4.8 Hz, 1 H, H2ЈЈ), 7.08–7.28 (m, 3 H, Har), 7.58 (d, J =
7.2 Hz, 1 H, Har) ppm. 13C NMR: δ = 23.6 (C6Ј), 26.9 (C8Ј), 27.1
(C3ЈЈ), 27.4 (C8Ј), 29.7 (C3Ј), 30.1 (C5Ј), 30.3 (C4ЈЈ), 32.2 (C7Ј),
43.1 (C4Ј), 55.0 (C3), 72.3 (C5), 84.5 (C1), 88.0 (C4), 104.6 (C2),
119.3 (C1Ј), 125.1 (C1ЈЈ), 125.5 (Car), 126.6(Car), 127.3(Car), 127.6
(Car), 127.7 (Car), 128.2 (Car), 128.7 (Car), 128.9 (Car), 130.2 (Car),
132.3(Car), 134.8 (C2ЈЈ), 135.2 (Car), 137.1 (Car), 137.6 (C2Ј) ppm.
FAB-MS: m/z (%) = 467 (20) [M + Na+], 427 (40) [M – OH] , 104
(100).
4-(Phenylethynyl)1-(triisopropylsilylethynyl)benzene (5c): 1H NMR
(CDCl3): δ = 1.11 (s, 21 H, TIPS), 7.16–7.37 (m, 9 H, Har) ppm.
13C NMR (CDCl3): δ = 11.3 (TIPS), 18.7 (TIPS), 88.1 (CϵC–Ar),
88.9 (CϵC–Si), 92.5 (CϵC–Ar), 105.6 (CϵC–Si), 123.9, 125.5,
126.3, 130.2, 130.8, 133.9, 134.7 (Car) ppm. C25H30Si (358.59), MS:
358 [M+], 269, 255, 241, 225, 183, 120.
1-(4-tert-Butylcyclohex-1-enyl)-8-(triisopropylsilyl)-1,7-octadiyne
(5d): 1H NMR (CDCl3): δ = 0.81 (s, 9 H, tBu),1.00 (s, 21 H, TIPS),
1.05–1.24 (m, 3 H, H3Ј,5Ј), 1.54 (m, 4 H, H4,5), 1.68–1.87 (m, 2
H, H3Ј,6Ј), 1.93–2.09 (m, 2 H, H4Ј,6Ј), 2.19 (t, J = 3.7 Hz, 2 H,
H6), 2.44 (t, J = 6.7 Hz, 2 H, H3), 5.97 (t, 1 H, J = 1.5, H2) ppm.
13C NMR (CDCl3): δ = 15.2 (TIPS), 18.6 (TIPS), 18.9 (C3), 19.3
(C6), 23.9 (C5), 27.2 (tBu), 27.3 (C3), 27.5 (C6), 31.0 (C4), 31.2
(C5), 32.2 (tBu), 43.4 (C4), 80.4 (CϵC–Si), 84.7 (CϵC–C), 86.9
Acknowledgments
U. H.-L. thanks the Daimler-Benz Foundation for a PhD fellow-
ship and A. V. the NATO for a postdoctoral fellowship. P. P. thanks
the “Institut Universitaire de France” for financial support. The
authors gratefully acknowledged financial support from the CNRS.
(CϵC–C), 108.5 (CϵC–Si), 120.9 (C1), 133.4 (C2Ј) ppm. IR: ν
˜
3052, 2959, 2253, 2171, 1422, 1265, 1047 cm–1. MS: 398 [M+], 355,
334, 291, 249, 207, 175, 129. HRMS C27H46Si: calcd. 398.3368,
found 398.3357.
[1] a) R. L. Caroll, C. B. Forman, Angew. Chem. Int. Ed. 2002, 41,
4378–4400; b) F. Diederich, P. J. Stang, R. R. Tykwinski (Eds.),
Acetylene Chemistry, VCH: Weinheim, 2004; H. Iwamura, K.
Matsuda, in: Modern Acetylene Chemistry (Eds.: P. J. Stang, F.
Diederich), Wiley-VCH: Weinheim, 1995, pp. 385–414; c) J. K.
Young, J. S. Moore, in: Modern Acetylene Chemistry, (Eds.: P. J.
Stang, F. Diederich), VCH: Weinheim, 1995, 416–442.
1-(3,4-Dihydronaphtyl)-8-(triisopropylsilyl)-1,7-octadiyne (5e): 1H
NMR (CDCl3): δ = 1.00 (s, 21 H, TIPS), 1.54 (m, 4 H, H4,5), 2.19
(t, J = 3.7 Hz, 2 H, H6), 2.37 (dt, J = 7.9, J = 4.8 Hz, 2 H, H3Ј),
2.44 (t, J = 6.7 Hz, 2 H, H3), 2.79 (t, J = 7.9 Hz, 2 H, H4Ј), 6.38
(t, J = 4.8 Hz, 1 H, H2Ј), 7.08–7.28 (m, 4 H, Har) ppm. 13C NMR
(CDCl3): δ = 15.2 (TIPS), 18.6 (TIPS), 19.1 (C3), 19.5 (C6), 22
Eur. J. Org. Chem. 2005, 2828–2834
www.eurjoc.org
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2833

U. Halbes-Létinois, A. Vasiliev, P. Pale
FULL PAPER
[2] a) K. C. Nicolaou, A. L. Smith, in: Modern Acetylene Chemis-
try, (Eds.: P. J. Stang, F. Diederich), VCH: Weinheim, 1995, pp.
203–283; b) A. Sorg, R. Brückner, Angew. Chem. Int. Ed. 2004,
43, 4523–4526; F. Bohlmann, T. Burkhardt, C. Zdero, Natu-
rally Occurring Acetylenes; Academic Press: New York; 1973;
c) F. Bellina, A. Carpita, L. Mannoci, R. Rossi, Eur. J. Org.
Chem. 2004, 26610–26619.
[3] a) Y. Zhao, K. Campbell, R. R. Tykwinski, J. Org. Chem. 2002,
67, 336–344; lit_bϾA. Kraft, A. C. Grimsdale, A. B. Holmes,
Angew. Chem. Int. Ed. 1998, 37, 402–428.
[10] a) J. Tsuji, Palladium Reagents and Cacatlysts, Wiley: New
York, 2004; b) E-i. Negishi, A. de Meijere, Handbook of Or-
ganopalladium Chemistry for Organic Synthesis Wiley: New
York, 2002; c) V. Farina, in Comprehensive Organometallic
Chemistry II, (Eds.: E. W. Abel, F. G. A. Stone, G. Wilkinson),
Pergamon: Oxford, 1995, vol. 12, pp. 222–225; d) K. Sonoga-
shira, in: Comprehensive Organic Chemistry (Eds.: I. Fleming,
B. M. Trost), Pergamon: Oxford, 1991, vol. 3, pp. 521–549.
[11] W. J. Scott, G. T. Crisp, J. K. Stille, Organic Synthesis 1991,
coll. vol. VIII, 97–103.
[4] a) J. Marsden, J. J. Miller, L. D. Shirtcliff, M. M. Haley, J. Am.
Chem. Soc. 2005, 127, 2462–2476; b) S. Ito, H. Inabe, N. Mor-
ita, A. Tajiri, Eur. J. Org. Chem. 2004, 1774–1780; c) R. Spre-
iter, C. Bosshard, G. Knöpfle, R. R. Tykwinski, M. Schreiber,
F. Diederich, J. Phys. Chem. B 1998, 102, 29–32.
[5] a) P. F. H. Schwab, B. C. Noll, J. Michl, J. Org. Chem. 2002,
67, 5476–5485; b) D. Zhao, J. S. Moore, J. Org. Chem. 2002,
67, 3548–3554.
[12] P. J. Stang, W. Trepdow, J. Med. Chem. 1981, 24, 468.
[13] D. L. Comins, A. Dehghani, Tetrahedron Lett. 1992, 33, 6299–
6302; G. T. Crisp, P. T. Glink, Tetrahedron 1992, 48, 3541–3556.
[14] S. Sibandhit, O. Lavastre, L. Ollivier, P. Dixneuf, Tetrahedron
1996, 52, 5495–5504.
[15] J. M. Tour, D. M. Shawn, Tetrahedron 2003, 59, 287–293.
[16] A similar triethynylated methanol has been described, where
TES was used instead of TMS, see: P. Manini, W. Amrein, V.
Gramlich, F. Diederich, Angew. Chem. Int. Ed. 2002, 41, 4339–
4343.
[6] P. Bertus, J.-H. Zhang, G. Sir, J.-M. Weibel, P. Pale, Tetrahedron
Lett. 2003, 44, 3391–3395.
[7] a) P. Bertus, P. Pale, Tetrahedron Lett. 1996, 37, 2019–2022; b)
P. Bertus, P. Pale, Tetrahedron Lett. 1997, 38, 8193–8196; c) P.
Bertus, P. Pale, J. Organomet. Chem. 1998, 567, 173–180.
[8] U. Halbes, P. Pale, Tetrahedron Lett. 2002, 43, 2039–2042.
[9] a) U. Halbes, P. Bertus, P. Pale, Tetrahedron Lett. 2001, 42,
8641–8644; b) P. Bertus, U. Halbes, P. Pale, Eur. J. Org. Chem.
2001, 4391–4393.
[17] A. I. Kovalev, K. Takeuchi, J. I. Sugiyama, M. Goyal, R. Na-
gata, A. L. Rusanov, M. Asai, A. V. Bazykin, M. Ueda, High
Perform. Polym. 2004, 16, 447–459.
Received: January 3, 2005
2834
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
Eur. J. Org. Chem. 2005, 2828–2834