Gold-catalyzed cycloisomerization of [3]-cumulenols

Article abstract of DOI:10.1016/j.jorganchem.2015.02.003

The gold-catalyzed cycloisomerization of tetrasubstituted [3]-cumulenols has been investigated. Overall, two main pathways are followed. In the presence of gold(III) catalysts, a dehydration process prevails giving diastereomerically pure dienynes while g

Full text of DOI:10.1016/j.jorganchem.2015.02.003

Accepted Manuscript
Gold-Catalyzed Cycloisomerization of [3]-Cumulenols
Laura Ferrand, Nicolas Das Neves, Max Malacria, Virginie Mouriès-Mansuy, Cyril
Ollivier, Louis Fensterbank
PII:
S0022-328X(15)00056-X
10.1016/j.jorganchem.2015.02.003
JOM 18898
DOI:
Reference:
To appear in: Journal of Organometallic Chemistry
Received Date: 16 December 2014
Revised Date: 2 February 2015
Accepted Date: 3 February 2015
Please cite this article as: L. Ferrand, N. Das Neves, M. Malacria, V. Mouriès-Mansuy, C. Ollivier,
L. Fensterbank, Gold-Catalyzed Cycloisomerization of [3]-Cumulenols, Journal of Organometallic
Chemistry (2015), doi: 10.1016/j.jorganchem.2015.02.003.
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ACCEPTED MANUSCRIPT
Synopsis. The gold-catalyzed cycloisomerization of tetrasubstituted [3]-cumulenols has been
investigated. Overall, two main pathways are followed. In the presence of a gold(III) catalyst,
a dehydration process prevails giving diastereomerically pure dienynes while gold(I) catalysts
favor the cycloisomerization to provide trisubstituted furan derivatives.

ACCEPTED MANUSCRIPT
Ph
Ph
5 mol% ClAuPPh3,
5 mol% AgOTf
Ph
O
Ph
Ph
Ph
Ph
HO
5 mol% AuBr3
Ph
Ph

ACCEPTED MANUSCRIPT
Gold-Catalyzed Cycloisomerization of [3]-Cumulenols
Laura Ferrand, †,‡ Nicolas Das Neves, †,‡ Max Malacria, †,‡ Virginie Mouriès-Mansuy, †,‡ Cyril
Ollivier†,‡*, Louis Fensterbank†,‡*
† Sorbonne Universités, UPMC Univ Paris 06, UMR 8232, Institut Parisien de Chimie Moléculaire, F-75252
Paris Cedex 05, France.
‡ CNRS, UMR 8232, Institut Parisien de Chimie Moléculaire, F 75252 Paris Cedex 05, France.
cyril.ollivier@upmc.fr; louis.fensterbank@upmc.fr
Tel: 00 33 1 44 27 38 47; Fax: 00 33 1 44 27 73 60
Abstract. The gold-catalyzed cycloisomerization of tetrasubstituted [3]-cumulenols has been
investigated. Overall, two main pathways are followed. In the presence of a gold(III) catalyst,
a dehydration process prevails giving diastereomerically pure dienynes while gold(I) catalysts
favor the cycloisomerization to provide trisubstituted furan derivatives.
1. Introduction
[n]-Cumulenes are fascinating molecules.[1] Their extreme level of unsaturation bodes well
for intriguing reactivities, especially in the presence of metallic species.[2] Nevertheless, the
game can be played only when the starting cumulene is readily available and stable enough to
be further engaged. Tetrasubstituted [3]-cumulenes meet these criteria and when armed with a
side hydroxy function, the corresponding 2,3,4-trien-1-ol systems become interesting
substrates to examine for electrophilic gold catalysis.[3] Assuming a preliminary electrophilic
activation of the π-system of the cumulene network, intramolecular nucleophilic attack from
the pendant hydroxy function is anticipated and should deliver an oxygen unsaturated
heterocycle presumably of furan type (eq. 1, Scheme 1).[4] Gold catalysis has provided
several versatile routes to furanic systems, most of them relying on a key C-O bond formation
from different type of unsaturated precursors bearing an alcohol or a ketone function.[5]
Furan moeties are widespread in natural products with relevant biological properties such as
kallolide A[6] and (−)-deoxypukalide.[7] They are also found in numerous drugs, for
instance the anti-ulcer drug ranitidine or the anti-bacterial furazilidone and have proven to be
valuable synthons for further elaboration.[8]
Closest to our approach is the report by Y. Liu who has recently examined the gold-catalyzed
cycloisomerization of [3]-cumulenones, obtained from diyne precursors, to provide furan
derivatives (eq. 2, Scheme 1).[2g] The same report also described the BrØnsted catalyzed
dehydration of the arylcumulenols to give the corresponding dienynes in good yields (eq. 3,
Scheme 1). It should also be mentioned that Skrydstrup developed a gold(I)-catalyzed double
hydratation of diyne substrates delivering 2,5-symmetrically substituted furans.[9] In this
context, our objective was to devise an access to trisubstituted furan derivatives directly from
1

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[3]-cumulenols. This implied to find the proper gold-based catalytic system which would be
compatible with the hydroxy function of the cumulenol system and not trigger a dehydrative
process. Indeed, this could be quite challenging since gold(III) salts have for instance been
shown to catalyze the nucleophilic substitution of propargylic alcohols.[10] Moreover, we
wanted to broaden the scope of the substituents on the final furanic products which implied to
engage diversely substituted cumulenols.
Scheme 1. Context of the [3]-cumulenol gold-catalyzed cycloisomerization
2. Results and discussion
2.1. Synthesis of precursors
For that purpose, we relied on the synthesis of [3]-cumulenols also documented by Y.
Liu,[11] who developed a zirconium-mediated coupling of 1,3-butadiynes with aldehydes. In
this work, we used bis-trimethylsilyl, bis-phenyl and bis-n-hexyl diynes as butadiynyl
substrates combined with cyclohexylaldehyde and various aryl aldehydes as electrophilic
partners. The expected representative [3]-cumulenols were produced satisfactorily as judged
from the examination of the 1H NMR spectra of the crude products (Scheme 2). Nevertheless,
we faced some difficulties at the purification stage in some cases. Chromatography of some
substrates, even with neutralized silica gel, leads to dehydration products 3 accompanied by
decomposition products. We thus devised a one pot sequence consisting of the synthesis of
the precursor 1 followed by a rapid filtration over silica gel neutralized by sodium carbonate.
The resulting product showed sufficient purity to be engaged in the cycloisomerization step
with gold catalysis.
2

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One pot sequence
1. R
R
R
R
2. R'CHO
Cp2ZrCl2
Cp2Zr
3. HCl 1M
+ 2 equiv EtMgBr
R'
HO
4. rapid filtration
1
Ph
Ph
Me3Si
SiMe3
[Au]
catalysis
R'
R'
HO
HO
R
R
1e, R' = 4-OMe-Ph
1f, R' = 4-NO2-Ph
1g, R' = cyclohexyl
1a, R' = Ph
R
and/or
1b, R' = 4-OMe-Ph
1c, R' = 4-F-Ph
1d, R' = cyclohexyl
R'
O
R
R'
3
2
n-Hex
n-Hex
Ph
HO
1h
Scheme 2. One pot sequence: [3]-cumulenol synthesis - gold-catalyzed step
2.2. Preliminary catalyst screening
Our preliminary catalyst screening was achieved with substrate 1a (Table 1) and provided
useful trends. Not surprisingly, the more electrophilic and oxophilic gold (III) salts[10,12,13]
favored the dehydration product 3a (entries 2-3). Same result was obtained with the oxophilic
AgOTf (entry 1).[14] In sharp contrast, gold (I) salt AuCl (entry 6) allowed to retrieve the
expected carbophilic activation favoring the exclusive formation of 2a. In the same line, a
complete selectivitity was also observed with cationic gold(I) complexes (entries 7-9).
Interestingly, a better yield was observed with a triflate counter ion compared to a
hexafluroantimonate (entry 7 vs. 8) which would be consistent with the fact that a triflate
anion has already been claimed as an efficient proton shuttle.[15] To pursue our study, we
selected AuBr3 to provide dienyne 3a and the AuClPPh3-AgOTf mixture as a priviledged
catalytic system since it provided the best yield of 2a in the shortest reaction time.
Entry Catalyst
Conversion
Yield[a] 2 : 3 ratio
1
2
3
4
5
6
7
8
9
AgOTf
AuBr3
AuCl3
AuCN
AuClPPh3
AuCl
AuClPPh3+AgOTf
AuClPPh3+AgSbF6
100 % after 18 h 51%
100 % after 18 h 59 %
100 % after 18 h 46 %
0 : 100
0 : 100
20 : 80
-
None after 24 h
None after 24 h
-
-
-
100 % after 56 h 53%
100% after 10 h 59%
100 : 0
100 : 0
100 : 0
100 : 0
33% after 18 h
27%
[JohnPhosAu(NCMe)]SbF6 100% after 42 h 47%
3

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[a] Overall yield from butadiyne precursor ; sequence run on a 1 mmol scale.
Table 1. Preliminary catalytic screening
2.3. Dehydration process
It appeared interesting to examine the possibility to develop a versatile access to dienyne
products 3. For that purpose, we submitted various cumulenols to gold(III) catalysis (Table 2).
As expected, bis-aryl cumulenol derivatives provided exclusively the dehydration products 3
in moderate to fair yields. Not surprisingly, para-fluoro substituted precursor (1c, entry 3)
resulted in a poorer reaction. In contrast, bis-TMS precursors gave inseparable mixtures of
products 2 and 3, featuring a significant influence of the R’ substituent (entries 5 vs. 6).
Partial desilylation on 2f or total one on 2g was observed which can be ascribed to the
presence of protic sources originating from the dehydration process. The more-electron
donating cyclohexyl resulted indeed in a logical higher yield of dienyne 3g. All dienynes 3
were isolated as single diastereomers.[16] Their structures were assigned by analogy with the
one of 3b which was secured by X-ray crystallography (Figure 1).[17]
Entry Cumulenols
Products
Yield[a], 2 : 3 ratio
1
59%, 0 : 100
1a
3a
3b
2
45%, 0 : 100
38%, 0 : 100
1b
3
1c
3c
4
5
56%, 0 : 100
52%, 62 : 38
1d
3d
1f[b]
2f
3f
4

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6[b]
1g[b]
69%, 23 : 77
O
2g
3g
[a] Overall yield from butadiyne precursor ; sequence run on a 1 mmol scale. [b] Reaction run
at 0.05 M.
Table 2. Gold (III)-catalyzed dehydration reaction
Figure 1. ORTEP diagram of 3b.
2.4. Cycloisomerization process
We then examined the behavior of these substrates when exposed to gold(I) catalysis
anticipating a higher π-activation of the cumulene moiety. We selected the 1 :1
AuClPPh3/AgOTf mixture as catalytic system. Gratifyingly, our working hypothesis proved
to be correct since bis-phenyl precursors 1a-1d cleanly afforded the corresponding furan
products in satisfactory yields, taking into account that it is an overall yield from the diyne
substrate. Here also, bis-TMS precursors gave contrasted results. Electron-richer substrate 1e
resulted in an equimolar mixture of products 2e and 3e, while precursors 1f and 1g
gratifyingly provided monodesilylated furans 2f and 2g’. In three instances, we used
Echavarren’s catalyst (entries 2, 3 and 6) but no improvement in the reaction outcome was
observed. Finally, dialkylsubstrate 1h also afforded a good yield of furan product 2h.
5

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Entry Cumulenols
Products
Yield[a], 2 : 3 ratio
1
2
3
4
6
59%, 100 : 0
1a
47%[b], 100 : 0
47%, 100 : 0
2a
3a
3c
3d
1b
1c
34%[b], 100 : 0
57%, 100 : 0
59%, 100 : 0
1d
1e[c]
55%, 50 : 50
complex mixture [b]
2e
3e
7
8
9
1f[c]
1g[c]
1h
36%, 100 : 0
50%, 100 : 0
52 %, 100 : 0
2f
2g’
2h
[a] Overall yield from butadiyne precursor ; sequence run on a 1 mmol scale.
[b] Reaction run with 5 mol% [JohnPhosAu(NCMe)]SbF6.
[c] Reaction run at 0.05 M.
Table 3. Gold (I)-catalyzed cycloisomerization
2.5. Mechanism proposal for the furan formation
A plausible mechanism for the furan formation can be proposed based on literature data
(Scheme 3). As for allenes,[18] preliminary π-activation of the cumulene moeity as in I would
generates a highly electrophilic complex that undergoes a 5-endo-dig cyclization. The
resulting vinylgold II intermediate then undergoes protodeauration, liberating the gold
catalyst and diene III. The latter then isomerizes to the aromatic furan substrates 2.
6

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Scheme 3. Mechanism proposol for the formation of furans
3. Conclusion
We have explored the reactivity of cumulenols towards gold catalysis. Because of the acidic
lability of the cumulenol substrates, we have worked out a multi-step reaction starting from
the zirconium mediated formation of the cumulenol from a diyne precursor, followed by rapid
filtration and the gold-catalyzed step. Overall, two main pathways are followed. In the
presence of gold(III) catalysts,
a
dehydration process takes place delivering
diastereomerically pure dienynes. In contrast, gold(I) catalysis offers an access to variously
trisubstituted furans. These findings illustrate the synthetic potential of the use of cumulenes
as partners in organometallic catalysis and more specifically upon π-activation of the
cumulene moiety. They also illustrate the fine tuning of catalysis provided by gold complexes
just by playing with the oxidation degree.
4. Experimental
General procedure of furan synthesis
EtMgBr (1.0 M in THF solution, 2.5 mL, 2.5 mmol) was added to a solution of ZrCp2Cl2
(0.365 g, 1.25 mmol) in THF (5 mL) at -50°C. The reaction mixture was stirred for 1 h at the
same temperature. Then, the diyne (1 mmol) was added and the reaction mixture was
warmed to room temperature and stirred for 2 h. Distilled aldehyde (1 mmol) was added ;
then the reaction mixture was stirred overnight and monitored by TLC (n-Pentane/EtOAc)
before being quenched with HCl 1M (3 mL). The aqueous layer was extracted with diethyl
ether. The combined organic layers were then washed with brine, dried over Na2SO4, filtered
and the solvent was evaporated under reduced pressure at 20°C. The crude residue was finally
filtered on silica gel neutralized with Na2CO3 to yield the [3]-cumulenol 1.
A solution of AuClPPh3 (24.7 mg, 0.05 mmol) and AgOTf (12.8 mg, 0.05 mmol) in CH2Cl2
(30 mL) was stirred for 5 min at room temperature and then cooled to -78°C. A solution of the
crude [3]-cumulenol 1 (ca. 1 mmol) in CH2Cl2 (10 mL) was added and the resulting mixture
was warmed to room temperature. The completion of the reaction was monitored by TLC (n-
Pentane/Et2O), the reaction mixture was filtered and the solvent was removed under reduced
pressure. Purification of the residue by flash chromatography (n-Pentane/EtOAc) afforded the
desired furan 2.
Acknowledgments. We thank the MRES, the CNRS, the IUF and the ANR Blan 0302
“Allènes” for financial support. Special thanks to Geoffrey Gontard (UPMC) for the X-ray
7

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structure determination of 3b. We also thank Lucas Defaut and Alexander V. Belovodski for
some experiments and Prof. Liu (Shanghai Institute of Organic Chemistry) for helpful
discussions.
Appendix A. Supplementary material
a) General procedures, characterization and spectral data (1H and 13C NMR spectra) of all
new compounds.
b) CCDC 1035348 contains the supplementary crystallographic data for this paper. These data
can be obtained free of charge from The Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/data_request/cif.
Supplementary data associated with this article can be found in online version at doi:
References
[1] For reviews, see: (a) L. Leroyer, V. Maraval, R. Chauvin, Chem. Rev. 112 (2012) 1310. (b) J. A.
Januszewski, R. R. Tykwinski, Chem. Soc. Rev. 43 (2014) 3184. (c) M. Ogasawara, in Science of synthesis.
Cumulenes and allenes, ed. D. Bellus, Georg Thieme Verlag (2008), vol. 44.1, pp. 9. (d) C. Bruneau, J.-L.
Renaud, in Compr. Org. Funct. Group Transform. II, ed. A. R. Katritzky and R. J. K. Taylor, Elsevier, Oxford
(2005) vol. 1.20, pp. 1019.
[2] (a) P. J. Stang, M. R. White, G. Maas, Organometallics 2 (1983) 720. (b) M. Iyoda, S. Tanaka, H. Otani, M.
Nose, M. Oda, J. Am. Chem. Soc. 110 (1988) 8494. (c) S. Hashmi, K. Polborn, G. Szeimies, Chem. Ber. 122
(1989) 2399. (d) N. Suzuki, M. Nishiura, Y. Wakatsuki, Science 295 (2002) 660. (e) T. Furuta, T. Asakawa, M.
Iiumina, S. Fujii, K. Tanaka, T. Kan, Chem. Commun. (2006) 3648. (f) N. Suzuki, Y. Fukuda, C. E. Kim, H.
Takahara, M. Iwasaki, M. Saburi, M. Nishiura, Y. Wakatsuki, Chem. Lett. 32 (2003) 16. (g) E. Wang, X. Fu, X.
Xie, J. Chen, H. Gao, Y. Liu, Tetrahedron Lett. 52 (2011) 1968.
[3] For recent monographs covering most aspects of gold catalysis, see: (a) Modern Gold Catalyzed Synthesis;
Hashmi, A. S. K., Toste, F. D., Eds.; Wiley-VCH: Weinheim, Germany, 2012. (b) Gold Catalysis: An
Homogenous Approach; Toste, F. D., Michelet, V., Eds.; Imperial College Press: London, 2014.
[4] For recent reviews on mechanistic aspects of gold-catalyzed reactions, see: (a) A. Fürstner, Chem. Soc. Rev.
38 (2009) 3208. (b) A. S. K. Hashmi, Angew. Chem. Int. Ed. 49 (2010) 5232. (c) C. Obradors, A. E. Echavarren,
Acc. Chem Res. 47 (2014) 902. (d) L. Fensterbank, M. Malacria, Acc. Chem. Res. 47 (2014) 953. (e) A. S. K.
Hashmi, Acc. Chem. Res. 47 (2014) 864.
[5] For seminal works, see: (a) A. S. K. Hashmi, L. Schwartz, J.-H. Choi, T. M. Frost, Angew. Chem. Int. Ed. 39
(2000) 2285. (b) T. Schwier, A. W. Sromek, D. M. L. Yap, D. Chernyak, V. Gevorgyan, J. Am. Chem. Soc. 129
(2007) 9868. (c) A. S. Dudnik, V. Gevorgyan, Angew. Chem. Int. Ed. (2007) 46, 5195. (c) A. S. K. Hashmi, T.
Häffner, M. Rudolph, F. Rominger, Eur. J. Org. Chem. (2011) 667. For reviews, see: (d) A. V. Gulevich, A. S.
Dudnik, N. Chernyak, V. Gevorgyan, Chem. Rev. 113 (2013) 3084. (e) N. Krause, C. Winter, Chem. Rev. 111
(2011) 1994. (f) A. Corma, A. Leyva-Perez, M. J. Sabater, Chem. Rev. 111 (2011) 1657. (g) M. Rudolph, A. S.
K. Hashmi, Chem. Commun. 47 (2011) 6536. For recent developments, see: (h) T. Wang, S. Shi, M. Rudolph,
A. S. K. Hashmi, Adv. Synth. Catal. 356 (2014) 2337. (i) T. Wang, S. Shi, M. M. Hansmann, E. Rettenmeier, M.
Rudolph, A. S. K. Hashmi, Angew. Chem. Int. Ed. 53 (2014) 3715. (j) S. Kramer, T. Skrydstrup, Angew. Chem.
Int. Ed. 51 (2012) 4681. (k) X. Huang, B. Peng, M. Luparia, L. Gomes, L. F. Veiros, N. Maulide, Angew. Chem.
Int. Ed. 51 (2012) 8886.
[6] S. A Look, M. T. Burch, W. Fenical, Z. Qi-tai, J. Clardy J. Org. Chem. 50 (1985) 5741.
[7] T. J. Donohoe, A. Ironmonger, N. M. Kershaw, Angew. Chem. Int. Ed. 47 (2008) 7314.
[8] (a) D. L. Wright, Prog. Het. Chem. 17 (2005) 1. (b) B. H. Lipschutz, Chem. Rev. 86 (1986) 795. (c) B. A.
Keay, Chem. Soc. Rev. 28 (1999) 209. (d) X. L. Hou, H. Y. Cheung, T. Y. Hon, P. L. Kwan, T. H. Lo,
S. Y. Tong, H. N.C. Wong, Tetrahedron 54 (1998) 1955.
[9] S. Kramer, J. L. H. Madsen, M. Rottländer, T. Skrydstrup, Org. Lett. 12 (2010) 2758.
[10] M. Georgy, V. Boucard, J.-M. Campagne, J. Am. Chem. Soc. 127 (2005) 14180-14181.
[11] Y. Liu, H. Gao, S. Zhou, Angew. Chem. Int. Ed. 45 (2006) 4163;
[12] For an evaluation of the Lewis acidity of various salts, see : Y. Yamamoto, J. Org. Chem.72 (2007) 7817.
[13] For examples of oxidation state dependent dichotomy in gold catalysis, see: (a) A. W. Sromek, M. Rubina,
V. Gevorgyan, J. Am. Chem. Soc. 127 (2005) 10500. (b) A. S. Dudnik, A. W. Sromek, M. Rubina, J. T. Kim, A.
V. Kel’in, V. Gevorgyan, J. Am. Chem. Soc. 130 (2008) 1440. (c) A. S. K. Hashmi, J. Hofmann, S. Shi, A.
8

ACCEPTED MANUSCRIPT
Schütz, M. Rudolph, C. Lothschütz, M. Wieteck, M. Bührle, M. Wölfle, F. Rominger, Chem. Eur. J. 19 (2013)
382.
[14] Y. Su, Y. Zhang, N. G. Akhmedov, J. L. Petersen, X. Shi, Org. Lett. 16 (2014) 2478.
[15] (a) J. Zhang, W. Shen, L. Li, M. Li, Organometallics 28 (2009) 3129 (b) C. M. Krauter, A. S. K. Hashmi,
M. Pernpointner, ChemCatChem 2 (2010) 1226 (c) M. Jiang, L.-P. Shi, Y. Li, Org. Lett. 12 (2010) 116.
(d) A. S. Dudnik, Y. Xia, Y. Li, V. Gevorgyan, J. Am. Chem. Soc. 132 (2010) 7645. (e) A. Zhdanko, M. E.
Maier, ASC Cat. 4 (2014) 2770.
[16] Minor diastereomers ( < 5 %) were detected on the 1H NMR of the crude product.
[17] CCDC 1035348.
[18] (a) B. Gockel, N. Krause, Org. Lett. 8 (2006) 4485. (b) R. Zriba, V. Gandon, C. Aubert, L. Fensterbank, M.
Malacria, Chem. Eur. J. 14 (2008) 1482. For reviews: (c) M. Malacria, L. Fensterbank, V. Gandon, Top. Curr.
Chem. 302 (2011) 157. (d) E. Soriano, I. Fernandez, Chem. Soc. Rev. 43 (2014) 3041.
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Highlights:
•
•
•
•
First gold-catalyzed cycloisomerization of cumulenols
Reaction outcome dependent from the gold oxidation state
A new access to trisubstituted furan derivatives
Gold(I) π-activation of the cumulene moeity

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SUPPORTING INFORMATION
Gold-Catalyzed Cycloisomerization of [3]-Cumulenols
Laura Ferrand, †,‡ Nicolas Das Neves, †,‡ Max Malacria, †,‡ Virginie Mouriès-Mansuy, †,‡ Cyril
Ollivier†,‡*, Louis Fensterbank†,‡*
† Sorbonne Universités, UPMC Univ Paris 06, UMR 8232, Institut Parisien de Chimie Moléculaire, F-75252
Paris Cedex 05, France.
‡ CNRS, UMR 8232, Institut Parisien de Chimie Moléculaire, F 75252 Paris Cedex 05, France.
Contents
1. General information
2. General procedures
3. Characterization data
4. Spectral data
2
3
4 -16
17 - 35
36
5. Crystal structure
1

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1. General information
Unless special mention, all reactions were carried out in oven-dried glassware under argon
atmosphere with magnetic stirring. All commercially available compounds were used as
received when not precised. Ethylmagnesium bromide was titrated with iodine in a 0.5 M
solution of lithium chloride in THF.[13]
Purifications
THF was purified either by distillation over Na/benzophenone or with the Puresolv Micro
solvent purification system, and CH2Cl2 was purified by distillation over CaH2. They all were
transferred under argon atmosphere.
Thin Layer Chromatography (TLC) was performed on Merck 60 F254 silica gel and revealed
with either a UV lamp (λ = 254 nm) or a specific color reagent (p-anisaldehyde). Davisil LC
60 A silica gel (40-63 µm) was used for flash chromatography.
Analyses
Melting points (m.p.) were measured on a Bibby Stuart Scientific melting point apparatus
SMP3 and were uncorrected.
IR spectra were recorded on a Bruker Tensor 27 ATR diamond PIKE Spectrophotometer.
Wavenumbers (ν) are given in cm-1.
1
NMR H, 13C, 19F spectra were recorded at 400, 100 and 376 MHz, respectively, using a
1
13
Bruker AVANCE 400 MHz spectrometer equipped with a BBFO probe. Some NMR H, C
were recorded at 300 and 75 MHz respectively, using a Bruker AVANCE 300 MHz
1
spectrometer. Chemical shifts (δ) are reported in ppm, using, for H and 13C, solvent residual
13
peak as internal standard references (CDCl3 : C = 77.16 ppm ; Residual CHCl3 in CDCl3 :
19
19
1H = 7.26 ppm) and using for F, trifluorotoluene as internal reference (C6H5CF3 : F = ‒
1
63.72 ppm). Signals were attributed with the help of H, 13C, DEPT-135, and HSQC
experiments. The letters m, s, d, t, sp and q stand for multiplet, singlet, doublet, triplet,
sextuplet and quartet, respectively. The letters b indicate that the signal is broad.
High resolution mass spectrometry (HRMS) analyses were performed at the IPCM on a
Bruker MicroTof mass spectrometer.
2

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2. General procedures
Typical procedure A for the synthesis of [3]-cumulenol
EtMgBr (1.0 M in THF solution, 2.5 mL, 2.5 mmol) was added to a solution of ZrCp2Cl2
(0.365 g, 1.25 mmol) in THF (5 mL) at ‒50°C. The reaction mixture was stirred for 1 h at the
same temperature. Then, the diyne (1 mmol) was added and the reaction mixture was warmed
to room temperature and stirred for 2 h. Distilled aldehyde (1 mmol) was added ; then the
reaction mixture was stirred overnight and monitored by TLC (n-Pentane/EtOAc) before
being quenched with HCl 1M (3 mL). The aqueous layer was extracted with diethyl ether (3 ×
10 mL). The combined organic layers were then washed with brine (3 × 10 mL), dried over
Na2SO4, filtered and the solvent was evaporated under reduced pressure at 20°C. The crude
residue was finally filtered through a pad of silica gel neutralised with Na2CO3 to yield [3]-
cumulenol. Analytical sample was purified for characterization.
Typical procedure B for the AuBr3-catalyzed reaction on [3]-cumulenol :
The crude [3]-cumulenol (ca. 1 mmol) was dissolved in CH2Cl2 (40 or 20 mL) and the
solution was cooled to ‒78°C, before AuBr3 (21.8 mg, 0.05 mmol) was added. The reaction
mixture was warmed to room temperature and stirred overnight. Then, the mixture was
filtered and the solvent was removed under reduced pressure. The crude residue was purified
by flash chromatography on silica gel (n-Pentane/EtOAc) affording the pure dienyne.
Typical procedure C for the AuPPh3OTf-catalyzed reaction on [3]-cumulenol :
A solution of AuClPPh3 (24.7 mg, 0.05 mmol) and AgOTf (12.8 mg, 0.05 mmol) in CH2Cl2
(30 or 10 mL) was stirred for 5 min at room temperature and then cooled to ‒78°C. A solution
of crude [3]-cumulenol (ca. 1 mmol) in CH2Cl2 (10 mL) was added and the resulting mixture
was warmed to room temperature and stirred for 10 h. After completion of the reaction
(monitored by TLC), the reaction mixture was filtered and the solvent was removed under
reduced pressure. Purification of the residue by flash chromatography (n-Pentane/EtOAc)
afforded the desired furan.
3

ACCEPTED MANUSCRIPT
3. Characterization Data for the Products
(E)-1,2,5-Triphenylhepta-2,3,4-trien-1-ol (1a)
Following general procedure A, using 1,4-diphenylbuta-1,3-diyne (0.202 g, 1 mmol) and
distilled benzaldehyde (0.10 mL, 1 mmol), [3]-cumulenol 1a was obtained as a brown oil.
1H NMR (300 MHz, CDCl3) : δ = 7.65 (2H, m), 7.55 (2H, m), 7.42-7.21 (11H, m), 5.97 (1H,
13
s), 2.64 (2H, q, J = 7.4 Hz), 2.58 (1H, bs), 1.18 (3H, t, J = 7.3 Hz) ; C NMR (100 MHz,
CDCl3) : δ = 154.8 (C), 154.6 (C), 142.6 (C), 138.5 (C), 137.3 (C), 128.7 (2 × CH), 128.7 (2
× CH), 128.7 (2 × CH), 128.1 (CH), 128.0 (CH), 127.6 (CH), 127.5 (2 × CH), 127.1 (2 ×
1
13
CH), 127.0 (2 × CH), 125.2 (C), 121.3 (C), 73.9 (CH), 26.5 (CH2), 13.1 (CH3). H and C
NMR data matched those reported in the literature.[10]
(E)-1-(4-Methoxyphenyl)-2,5-diphenylhepta-2,3,4-trien-1-ol (1b)
Following general procedure A, using 1,4-diphenylbuta-1,3-diyne (0.202 g, 1 mmol) and
distilled p-anisaldehyde (0.12 mL, 1 mmol), [3]-cumulenol 1b was obtained as a yellow oil.
1H NMR (400 MHz, CDCl3) : δ = 7.66 (2H, d, J = 7.2 Hz), 7.60 (2H, d, J = 7.6 Hz), 7.46
(2H, d, J = 8.4 Hz), 7.40 (2H, t, J = 7.2 Hz), 7.33-7.31 (4H, m), 6.89 (2H, d, J = 8.8 Hz), 5.90
13
(1H, s), 3.80 (3H, s), 2.68 (2H, q, J = 7.2 Hz), 2.55 (1H, bs), 1.23 (3H, t, J = 7.2 Hz) ; C
NMR (100 MHz, CDCl3) : δ = 159.5 (C), 154.8 (C), 154.4 (C), 138.6 (C), 137.3 (C), 134.8
(C), 128.7 (4 × CH), 128.5 (2 × CH), 128.1 (CH), 127.6 (CH), 127.5 (2 × CH), 127.0 (2 ×
CH), 124.9 (C), 121.6 (C), 114.2 (2 × CH), 73.5 (CH), 55.4 (CH3), 26.5 (CH2), 13.1 (CH3) ;
HRMS (ESI) : calcd for C26H24NaO2 [M + Na]+: 391.1669; found 391.1683 ; IR (ATR) : ν =
3425, 3060, 2969, 1678, 1646, 1612, 1512, 1491, 1447, 1248, 1175, 1031, 834, 754, 691 cm-1.
4

ACCEPTED MANUSCRIPT
(E)-1-(4-Fluorophenyl)-2,5-diphenylhepta-2,3,4-trien-1-ol (1c)
Following general procedure A, using 1,4-diphenylbuta-1,3-diyne (0.202 g, 1 mmol) and 4-
fluorobenzaldehyde (0.11 mL, 1 mmol), [3]-cumulenol 1c was obtained as a yellow oil.
1H NMR (400 MHz, CDCl3) : δ = 7.66-7.60 (4H, m), 7.53-7.48 (2H, m), 7.42-7.23 (6H, m),
7.08-7.02 (2H, m), 5.95 (1H, s), 2.64 (2H, q, J = 7.2 Hz), 2.64 (1H, bs), 1.18 (3H, t, J = 7.2
13
Hz) ; C NMR (100 MHz, CDCl3) : δ = 162.6 (C, d, J = 245 Hz), 154.8 (C), 154.5 (C),
138.4 (C), 138.3 (C, d, J = 4.0 Hz), 137.1 (C), 128.9 (2 × CH, d, J = 9.0 Hz), 128.8 (2 × CH),
128.7 (2 × CH), 128.2 (CH), 127.8 (CH), 127.5 (2 × CH), 127.1 (2 × CH), 125.6 (C), 121.0
19
(C), 115.5 (2 × CH, d, J = 21.0 Hz), 73.3 (CH), 26.5 (CH2), 13.0 (CH3) ; F NMR (376
MHz, CDCl3) : δ = -115.7 ; HRMS (ESI) : calcd for C25H21FNaO [M + Na]+: 379.1469;
found 379.1478 ; IR (ATR) : ν = 3380, 3059, 2970, 1684, 1647, 1601, 1509, 1491, 1448,
1221, 1157, 841, 754, 690 cm-1.
(E)-1-Cyclohexyl-2,5-diphenylhepta-2,3,4-trien-1-ol (1d)
Following general procedure A, using 1,4-diphenylbuta-1,3-diyne (0.202 g, 1 mmol) and
distilled cyclohexane carboxaldehyde (0.12 mL, 1 mmol), [3]-cumulenol 1d was obtained as a
yellow oil.
1H NMR (400 MHz, CDCl3) : δ = 7.64 (4H, dd, J = 8.4, 1.2 Hz), 7.41-7.36 (4H, m), 7.29
(1H, bt, J = 1.2 Hz), 7.27 (1H, bt, J = 1.6 Hz), 4.66 (1H, bd, J = 5.6 Hz), 2.77 (2H, qd, J =
7.2, 2.0 Hz), 2.11-1.91 (2H, m), 1.85-1.59 (6H, m), 1.37 (3H, t, J = 7.2 Hz), 1.32-1.10 (6H,
m) ; 13C NMR (100 MHz, CDCl3) : δ = 154.6 (C), 153.5 (C), 138.7 (C), 138.0 (C), 128.8 (2
× CH), 128.7 (2 × CH), 127.9 (CH), 127.7 (CH), 127.5 (2 × CH), 126.9 (2 × CH), 123.8 (C),
122.1 (C), 75.9 (CH), 43.6 (CH), 30.4 (CH2), 27.4 (CH2), 26.6 (CH2), 26.5 (CH2), 26.4 (CH2),
26.2 (CH2), 13.2 (CH3) ; HRMS (ESI) : calcd for C25H28NaO [M + Na]+: 367.2032; found
367.2025 ; IR (ATR) : ν = 3440, 3059, 2930, 1650, 1595, 1492, 1448, 1262, 1077, 754, 690
cm-1.
5

ACCEPTED MANUSCRIPT
(Z)-1-(4-Methoxyphenyl)-2,5-bis(trimethylsilyl)hepta-2,3,4-trien-1-ol (1e)
Following general procedure A, using 1,4-bis(triméthylsilyl)buta-1,3-diyne (0.198 g, 1 mmol)
and distilled p-anisaldehyde (0.12 mL, 1 mmol), [3]-cumulenol 1e was obtained as a yellow
oil.
1H NMR (400 MHz, CDCl3) : δ = 7.29 (2H, d, J = 8.6 Hz), 6.87 (2H, d, J = 8.6 Hz), 5.34
(1H, d, J = 5.2 Hz), 3.79 (3H, s), 2.86 (1H, d, J = 5.4 Hz), 2.37 (2H, q, J = 7.2 Hz), 1.12 (3H,
t, J = 7.2 Hz), 0.21 (9H, s), 0.04 (9H, s) ; 13C NMR (100 MHz, CDCl3) : δ = 170.8 (C), 170.0
(C), 159.4 (C), 135.3 (C), 134.0 (C), 130.3 (C), 128.8 (2 × CH), 113.9 (2 × CH), 75.8 (CH),
55.3 (CH3), 29.0 (CH2), 13.5 (CH3), ‒ 0.6 (3 × CH3), ‒ 1.3 (3 × CH3). 1H and 13C NMR data
matched those reported in the literature.[10]
(Z)-1-(4-Nitrophenyl)-2,5-bis(trimethylsilyl)hepta-2,3,4-trien-1-ol (1f)
Following general procedure A, using 1,4-bis(triméthylsilyl)buta-1,3-diyne (0.198 g, 1 mmol)
and 4-nitrobenzaldehyde 98 % (0.153g, 1 mmol), [3]-cumulenol 1f was obtained as a yellow
oil.
1H NMR (300 MHz, CDCl3) : δ = 8.20 (2H, d, J = 8.7 Hz), 7.54 (2H, d, J = 8.7 Hz), 5.50
(1H, d, J = 4.9 Hz), 2.80 (1H, d, J = 5.1 Hz), 2.34 (2H, q, J = 7.2 Hz), 1.02 (3H, t, J = 7.2 Hz),
0.19 (9H, s), 0.09 (9H, s) ; 13C NMR (75 MHz, CDCl3) : δ = 173.5 (C), 169.7 (C), 150.6 (C),
147.5 (C), 137.5 (C), 128.0 (2 × CH), 127.9 (C), 123.7 (2 × CH), 75.6 (CH), 29.3 (CH2),
13.37 (CH3), ‒0.42 (3 × CH3), ‒1.27 (3 × CH3). 1H and 13C NMR data matched those reported
in the literature.[10]
6

ACCEPTED MANUSCRIPT
(Z)-1-Cyclohexyl-2,5-bis(trimethylsilyl)hepta-2,3,4-trien-1-ol (1g)
Following general procedure A, using 1,4-bis(triméthylsilyl)buta-1,3-diyne (0.198 g, 1 mmol)
and distilled cyclohexane carboxaldehyde (0.12 mL, 1 mmol), [3]-cumulenol 1g was obtained
as a yellow oil.
1H NMR (400 MHz, CDCl3) : δ =4.16 (1H, m), 2.36 (2H, qd, J = 7.2, 1.2 Hz), 2.06 (1H, d, J
= 6.8 Hz), 1.78-1.61 (5H, m), 1.60-1.53 (1H,m), 1.35-0.97 (5H, m), 1.13 (3H, t, J = 7.2 Hz),
13
0.19 (9H, s), 0.18 (9H, s) ; C NMR (100 MHz, CDCl3) : δ = 171.1 (C), 170.9 (C), 133.6
(C), 130.4 (C), 78.2 (CH), 44.1 (CH), 30.8 (CH2), 29.0 (CH2), 26.8 (CH2), 26.6 (CH2), 26.4
(CH2), 26.2 (CH2), 13.5 (CH3), ‒0.5 (3 × CH3), ‒1.2 (3 × CH3) ; HRMS (ESI) : calcd for
C19H36NaOSi2 [M + Na]+: 359.2197; found 359.2203 ; IR (ATR) : ν = 3460, 2924, 1677,
1586, 1245, 833 cm-1.
(E)-5-Ethyl-2-hexyl-1-phenylundeca-2,3,4-trien-1-ol (1h)
Following general procedure A, using 7,9-hexadecadiyne (0.26 mL, 1 mmol) and distilled
benzaldehyde (0.10 mL, 1 mmol), [3]-cumulenol 1a was obtained as a yellow oil. Purification
by flash chromatography for characterization afforded the [3]-cumulenol as a white solid.
m.p. = 44 °C ; 1H NMR (400 MHz, CDCl3) : δ = 7.40-7.32 (4H, m), 7.27 (1H, m), 5.15 (1H,
bd, J = 4.4 Hz), 2.60 (1H, d, J = 4.8 Hz), 2.21-2.17 (4H, m), 2.03 (2H, m), 1.60-1.49 (4H, m),
1.41-1.17 (12H, m), 1.11 (3H, t, J = 7.6 Hz), 0.93-0.82 (6H, m) ; 13C NMR (100 MHz,
CDCl3) : δ = 156.7 (C), 154.7 (C), 142.6 (C), 128.5 (2 × CH), 127.8 (CH), 127.0 (2 × CH),
123.8 (C), 119.7 (C), 76.3 (CH), 36.4 (CH2), 32.0 (CH2), 31.9 (2 x CH2), 29.5 (CH2), 29.2
(CH2), 29.1 (CH2), 28.0 (CH2), 27.9 (CH2), 22.8 (CH2), 22.7 (CH2), 14.2 (2 × CH3), 12.5
(CH3) ; HRMS (ESI) : calcd for C25H38NaO [M + Na]+: 377.2815; found 377.2802 ; IR
(ATR) : ν = 3375, 3029, 2927, 1620, 1467, 1039, 764, 700 cm-1.
7

ACCEPTED MANUSCRIPT
2,3-Diphenyl-5-(1-phenylpropyl)furan (2a)
Following general procedure C on [3]-cumulenol 1a in CH2Cl2 (40 mL), the furan 2a was
obtained after flash chromatography on silica gel (n-Pentane/EtOAc, 99/1 to 98/2) as a yellow
oil (0.199 g, 0.59 mmol, 59 %).
1H NMR (400 MHz, CDCl3) : δ = 7.59-7.56 (2H, m), 7.49-7.46 (2H, m), 7.43-7.7.37 (6H,
m), 7.35-7.29 (4H, m), 7.25 (1H, m), 6.26 (1H, d, J = 0.8 Hz), 3.97 (1H, t, J = 7.7 Hz), 2.32
13
(1H, m), 2.07 (1H, m), 1.05 (3H, t, J = 7.2 Hz) ; C NMR (100 MHz, CDCl3) : δ = 157.4
(C), 147.2 (C), 142.6 (C), 134.8 (C), 131.6 (C), 128.8 (2 × CH), 128.7 (2 × CH), 128.6 (2 ×
CH), 128.4 (2 × CH), 128.2 (2 × CH), 127.2 (CH), 127.1 (CH), 126.7 (CH), 126.1 (2 × CH),
123.0 (C), 110.1 (CH), 47.4 (CH), 28.1 (CH2), 12.6 (CH3) ; HRMS (ESI) : calcd for
C25H22NaO [M + Na]+: 361.1563; found 361.1585 ; IR (ATR) : ν = 3028, 2964, 1600, 1553,
1503, 1451, 1253, 763, 696 cm-1.
2-(4-Methoxyphenyl)-3-phenyl-5-(1-phenylpropyl)furan (2b)
Following general procedure C on [3]-cumulenol 1b in CH2Cl2 (40 mL), the furan 2b was
obtained after flash chromatography on silica gel (n-Pentane/EtOAc, 98/2) as a yellow oil
(0.173 mg, 0.47 mmol, 47 %).
1H NMR (400 MHz, CDCl3) : δ = 7.47-7.40 (4H, m), 7.39-7.32 (6H, m), 7.30-7.25 (2H, m),
7.25 (12H, m), 6.84 (2H, d, J = 8.8 Hz), 6.21 (1H, d, J = 0.8 Hz), 3.91 (1H, bt, J = 7.6 Hz),
13
3.81 (3H, s), 2.27 (1H, m), 2.02 (1H, m), 1.00 (3H, t, J = 7.6 Hz) ; C NMR (100 MHz,
CDCl3) : δ = 159.0 (C), 156.8 (C), 147.3 (C), 142.7 (C), 135.0 (C), 128.7 (2 × CH), 128.6 (4
× CH), 128.2 (2 × CH), 127.7 (2 × CH), 126.9 (CH), 126.7 (CH), 124.5 (C), 121.5 (C), 113.9
(2 × CH), 109.7 (CH), 55.4 (CH3), 47.4 (CH), 28.1 (CH2), 12.6 (CH3) ; HRMS (ESI) : calcd
for C26H24NaO2 [M + Na]+: 391.1669; found 391.1661 ; IR (ATR) : ν = 3028, 2962, 1598,
1511, 1463, 1248, 832, 729, 698 cm-1.
8

ACCEPTED MANUSCRIPT
2-(4-Fluorophenyl)-3-phenyl-5-(1-phenylpropyl)furan (2c)
Following general procedure C on [3]-cumulenol 1c in CH2Cl2 (40 mL), the furan 2c was
obtained after flash chromatography on silica gel (n-Pentane/EtOAc, 99/1 to 98/2) as a yellow
oil (0.203 g, 0.57 mmol, 57 %).
1H NMR (400 MHz, CDCl3) : δ = 7.44 (2H, m), 7.39-7.22 (10H, m), 6.95 (2H, m), 6.18 (1H,
d, J = 0.6 Hz), 3.88 (1H, t, J = 7.7 Hz), 2.23 (1H, m), 1.99 (1H, m), 0.97 (3H, t, J = 7.4 Hz) ;
13C NMR (100 MHz, CDCl3) : δ = 162.0 (C, d, J = 246 Hz), 157.4 (C), 146.3 (C), 142.4 (C),
134.6 (C), 128.7 (2 × CH), 128.7 (2 × CH), 128.6 (2 × CH), 128.2 (2 × CH), 127.9 (2 × CH,
d, J = 8 Hz), 127.8 (C, d, J = 3 Hz), 127.2 (CH), 126.8 (CH), 122.7 (C), 115.4 (2 × CH, d, J =
21 Hz), 110.0 (CH), 47.4 (CH), 28.1 (CH2), 12.6 (CH3) ; 19F NMR (376 MHz, CDCl3) : δ =
‒115.4 ; HRMS (ESI) : calcd for C25H21FKO [M + K]+: 395.1208; found 395.1198 ; IR
(ATR) : ν = 3029, 2964, 1602, 1555, 1510, 1489, 1451, 1235, 1158, 838, 764, 699 cm-1.
2-Cyclohexyl-3-phenyl-5-(1-phenylpropyl)furan (2d)
Following general procedure C on [3]-cumulenol 1d in CH2Cl2 (40 mL), the furan 2d was
obtained after flash chromatography on silica gel (n-Pentane/EtOAc, 98/2) as an yellow oil
(0.203 g, 0.59 mmol, 59 %).
1H NMR (400 MHz, CDCl3) : δ = 7.38-7.17 (10H, m), 6.06 (1H, s), 3.81 (1H, t, J = 7.6 Hz),
2.84 (1H, tt, J = 11.9, 3.3 Hz), 2.17 (1H, m), 2.0-1.74 (5H, m), 1.74-1.52 (3H, m), 1.24-1.33
(3H, m), 0.93 (3H, t, J = 7.2 Hz) ; 13C NMR (100 MHz, CDCl3) : δ = 155.6 (C), 154.5 (C),
143.1 (C), 135.0 (C), 128.6 (2 × CH), 128.5 (2 × CH), 128.2 (2 × CH), 128.0 (2 × CH), 126.5
(CH), 126.2 (CH), 119.8 (C), 107.2 (CH), 47.4 (CH), 36.5 (CH), 32.1 (CH2), 32.0 (CH2), 28.3
(CH2), 26.6 (CH2), 26.5 (CH2), 26.1 (CH2), 12.6 (CH3) ; HRMS (ESI) : calcd for C25H29O [M
+ H]+: 345.2213; found 345.2211 ; IR (ATR) : ν = 3028, 2929, 2853, 1600, 1560, 1494,
1449, 1219, 976, 763, 698 cm-1.
9

ACCEPTED MANUSCRIPT
(2-(4-Methoxyphenyl)-5-propylfuran-3-yl)trimethylsilane (2e)
Following general procedure C on [3]-cumulenol 1e in CH2Cl2 (20 mL), the furan 2e was
obtained after flash chromatography on silica gel (n-Pentane/EtOAc, 98/2) as a yellow oil
corresponding to an inseparable mixture with dienyne 3e (0.173 g, 0.55 mmol, 55 % with a
ratio 2e/3e of 50/50).
1H NMR (400 MHz, CDCl3) : δ = 7.52 (2H, d, J = 8.8 Hz), 6.93 (2H, d, J = 8.4 Hz), 6.04
(1H, d, J = 1.2 Hz), 3.85 (3H, s), 2.65 (2H, t, J = 7.6 Hz), 1.73 (2H, sp, J = 7.2 Hz), 1.02 (3H,
13
t, J = 7.2 Hz), 0.24 (9H, s) ; C NMR (100 MHz, CDCl3) : δ = 159.2 (C), 157.1 (C), 155.3
(C), 130.4 (C), 128.6 (2 × CH), 126.0 (C), 113.7 (2 × CH), 111.7 (CH), 55.4 (CH3), 30.1
(CH2), 21.6 (CH2), 14.1 (CH3), 0.1 (3 × CH3) ; HRMS (ESI) : calcd for C17H25O2Si [M +
H]+: 289.1618 ; found 289.1623.
Trimethyl(2-(4-nitrophenyl)-5-propylfuran-3-yl)silane (2f)
Following general procedure C on [3]-cumulenol 1f in CH2Cl2 (20 mL), the furan 2f was
obtained after flash chromatography on silica gel (n-Pentane/EtOAc, 98/2) as a yellow oil
(0.109 g, 0.36 mmol, 36 %).
1H NMR (400 MHz, CDCl3) : δ = 8.26 (2H, d, J = 8.8 Hz), 7.77 (2H, d, J = 8.8 Hz), 6.16
(1H, t, J = 0.8 Hz), 2.70 (2H, t, J = 7.2 Hz), 1.76 (2H, sp, J = 7.6 Hz), 1.04 (3H, t, J = 7.4 Hz),
0.33 (9H, s) ; 13C NMR (100 MHz, CDCl3) : δ = 157.9 (C), 154.1 (C), 146.3 (C), 138.7 (C),
126.4 (2 × CH), 123.9 (2 × CH), 120.2 (C), 113.5 (CH), 30.0 (CH2), 21.5 (CH2), 14.0 (CH3), ‒
0.1 (3 × CH3) ; HRMS (ESI) : calcd for C16H21LiNO3Si [M + Li]+: 310.1446; found
310.1453 ; IR (ATR) : ν = 2960, 1598, 1579, 1513, 1333, 1251, 1109, 836, 753, 696 cm-1.
10

ACCEPTED MANUSCRIPT
2-Cyclohexyl-5-propylfuran (2g)
Following general procedure B on [3]-cumulenol 1g in CH2Cl2 (20 mL), the furan 2g was
obtained after flash chromatography on silica gel (n-Pentane to n-Pentane/EtOAc, 98/2) as a
yellowish oil corresponding to a mixture with dienyne 3g (0.198 g, 0.69 mmol, 69 % with a
ratio 2g/3g of 23/77).
1H NMR (400 MHz, CDCl3) : δ = 5.85 (1H, d, J = 2.8 Hz), 5.81 (1H, d, J = 2.8 Hz), 2.60-
2.53 (3H, m), 2.07-1.95 (2H, m), 1.82-1.59 (5H, m), 1.42-1.21 (5H, m), 0.95 (3H, t, J = 7.4
Hz) ; 13C NMR (100 MHz, CDCl3) : δ = 159.4 (C), 154.4 (C), 104.9 (CH), 102.9 (CH), 37.4
(CH), 31.8 (2 × CH2), 30.3 (CH2), 26.3 (CH2), 26.1 (2 × CH2), 21.6 (CH2), 13.9 (CH3) IR
(ATR) : ν = 2928, 1564, 1450, 1248cm-1.
(2-Cyclohexyl-5-propylfuran-3-yl)trimethylsilane (2g’)
Following general procedure C on [3]-cumulenol 1g in CH2Cl2 (20 mL), the furan 2g’ was
obtained after flash chromatography on silica gel (n-Pentane) as a yellowish oil (0.132 g, 0.50
mmol, 50 %).
1H NMR (400 MHz, CDCl3) : δ = 5.81 (1H, t, J = 0.9 Hz), 2.63 – 2.53 (3H, m), 1.85-1.60
13
(9H, m), 1.35-1.28 (3H, m), 0.98 ( 3H, t, J = 7.4 Hz), 0.21 ( 9H, s) ; C NMR (100 MHz,
CDCl3) : δ = 163.8 (C), 154.1 (C), 110.9 (C), 109.0 (CH), 39.2 (CH), 32.5 (2 × CH2), 30.1
(CH2), 26.8 (2 × CH2), 26.1 (CH2), 21.6 (CH2), 14.1 (CH3), 0.1 (3 × CH3) ; IR (ATR) : ν =
2958, 2930, 2852, 1552, 1450, 1247cm-1.
11

ACCEPTED MANUSCRIPT
3-Hexyl-5-(nonan-3-yl)-2-phenylfuran (2h)
Following general procedure C on [3]-cumulenol 1h in CH2Cl2 (20 mL), the furan 2h was
obtained after flash chromatography on silica gel (n-Pentane) as a yellow oil (0.185 g, 0.52
mmol, 52 %).
1H NMR (400 MHz, CDCl3) : δ = 7.58 (2H, d, J = 8.0 Hz), 7.38 (2H, t, J = 7.6 Hz), 7.21
(1H, t, J = 7.2 Hz), 5.97 (1H, s), 2.65-2.55 (3H, m), 1.69-1.60 (6H, m), 1.45-1.23 (14H, m),
0.91-0.86 (9H, m) ; 13C NMR (100 MHz, CDCl3) : δ = 157.9 (C), 146.3 (C), 132.6 (C), 128.6
(2 × CH), 126.2 (CH), 125.2 (2 × CH), 122.4 (C), 109.1 (CH), 40.8 (CH), 33.8 (CH2), 32.0
(CH2), 31.9 (CH2), 30.1 (CH2), 29.5 (CH2), 29.4 (CH2), 27.5 (CH2), 27.2 (CH2), 26.3 (CH2),
22.8 (2 × CH2), 14.2 (2 × CH3), 12.0 (CH3) ; HRMS (ESI) : calcd for C25H38NaO [M + Na]+:
377.2815; found 377.2828 ; IR (ATR) : ν = 3060, 2927, 1599, 1552, 1491, 1465, 1069, 761,
692 cm-1.
(1Z,5Z)-Hepta-1,5-dien-3-yne-1,2,5-triyltribenzene (3a)
Following general procedure B on [3]-cumulenol 1a in CH2Cl2 (40 mL), the dienyne 3a was
obtained after flash chromatography on silica gel (n-Pentane/EtOAc, 95/5) as a yellowish
solid (0.189 g, 0.59 mmol, 59 %).
m.p. = 88 °C ; 1H NMR (400 MHz, CDCl3) : δ = 8.01 (2H, d, J = 7.2 Hz), 7.80 (2H, d, J =
7.6 Hz), 7.63 (2H, d, J = 7.6 Hz), 7.41 (2H, t, d, J = 7.2 Hz), 7.36-7.26 (7H, m), 7.21 (1H, s),
6.54 (1H, q, J = 6.8 Hz), 2.15 (3H, d, J = 7.1 Hz) ; 13C NMR (100 MHz, CDCl3 ) : δ = 140.2
(C), 138.5 (C), 136.8 (C), 134.8 (CH), 134.3 (CH), 129.2 (2 × CH), 128.6 (2 × CH), 128.5 (2
× CH), 128.4 (3 × CH), 128.0 (CH), 127.6 (CH), 126.8 (2 × CH), 126.3 (2 × CH), 125.1 (C),
122.4 (C), 94.8 (C), 94.6 (C), 17.2 (CH3) ; HRMS (ESI) : calcd for C25H20Na [M + Na]+:
343.1457; found 343.1455 ; IR (ATR) : ν = 3060, 1595, 1488, 1447, 760, 689 cm-1.
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((1Z,5Z)-1-(4-Methoxyphenyl)hepta-1,5-dien-3-yne-2,5-diyl)dibenzene (3b)
Following general procedure B on [3]-cumulenol 1b in CH2Cl2 (40 mL), the dienyne 3b was
obtained after flash chromatography on silica gel (n-Pentane to n-Pentane/EtOAc 95/5) as an
orange oil (0.157 g, 0.45 mmol, 45 %). Suitable X-ray crystals were obtained by
crystallization in n-Pentane.
m.p. = 114 °C ; 1H NMR (400 MHz, CDCl3) : δ = 8.01 (2H, d, J = 8.4 Hz), 7.81 (2H, d, J =
7.2 Hz), 7.67 (2H, d, J = 7.2 Hz), 7.49-7.28 (6H, m), 7.17 (1H, s), 6.89 (2H, d, J = 8.8 Hz),
6.55 (1H, q, J = 7.2 Hz), 3.85 (3H, s), 2.18 (3H, d, J = 7.2 Hz) ; 13C NMR (100 MHz,
CDCl3) : δ 159.8 (C), 140.4 (C), 138.6 (C), 134.4 (CH), 133.9 (CH), 130.7 (2 × CH), 129.7
(C), 128.6 (2 × CH), 128.5 (2 × CH), 127.7 (CH), 127.6 (CH), 126.6 (2 × CH), 126.4 (2 ×
CH), 125.2 (C), 120.0 (C), 113.8 (2 × CH), 94.9 (C), 94.4 (C), 55.4 (CH3), 17.3 (CH3) ;
HRMS (ESI) : calcd for C26H23O [M + H]+: 351.1743; found 351.1750 ; IR (ATR) : ν =
3005, 2902, 2835, 1600, 1505, 1446, 1244, 864, 832, 802, 765, 750, 692 cm-1.
((1Z,5Z)-1-(4-Fluorophenyl)hepta-1,5-dien-3-yne-2,5-diyl)dibenzene (3c)
Following general procedure B on [3]-cumulenol 1c in CH2Cl2 (40 mL), the dienyne 3c was
obtained after flash chromatography on silica gel (n-Pentane to n-Pentane/EtOAc, 95/5) as a
white solid (0.136 g, 0.38 mmol, 38 %).
m.p. = 94 °C ; 1H NMR (300 MHz, CDCl3) : δ = 7.97 (2H, dd, J = 8.7, 5.4 Hz), 7.78 (2H, d,
J = 7.2 Hz), 7.59 (2H, d, J = 6.9 Hz), 7.43-7.29 (6H, m), 7.15 (1H, s), 7.01 (2H, t, J = 8.7 Hz),
6.54 (1H, q, J = 6.9 Hz), 2.14 (3H, d, J = 6.9 Hz) ; 13C NMR (100 MHz, CDCl3) : δ =162.5
(C, d, J = 248 Hz) , 140.0 (C), 138.4 (C), 134.4 (CH), 133.4 (CH), 133.0 (C, d, J = 3 Hz),
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131.0 (2 × CH, d, J = 8.0 Hz), 128.6 (2 × CH), 128.5 (2 × CH), 128.1 (CH), 127.7 (CH),
126.7 (2 × CH), 126.3 (2 × CH), 125.0 (C), 122.1 (C, d, J = 2.0 Hz), 115.3 (2 × CH, d, J =
22.0 Hz), 94.8 (C), 94.4 (C), 17.2 (CH3) ; 19F NMR (376 MHz, CDCl3) : δ = ‒113.3 ; HRMS
(ESI) : calcd for C25H19FNa [M + Na]+: 361.1363; found 361.1366 ; IR (ATR) : ν = 3034,
2940, 1599, 1507, 1448, 1233, 1159, 830, 759, 693 cm-1.
((1Z,5Z)-1-Cyclohexylhepta-1,5-dien-3-yne-2,5-diyl)dibenzene (3d)
Following general procedure B on [3]-cumulenol 1d in CH2Cl2 (40 mL), the dienyne 3d was
obtained after flash chromatography on silica gel (n-Pentane to n-Pentane/EtOAc, 95/5) as a
yellowish oil (0.183 g, 0.56 mmol, 56 %).
1H NMR (400 MHz, CDCl3) : δ = 7.67 (4H, m), 7.37-7.27 (6H, m), 6.54 (1H, q, J = 7.2 Hz),
6.31 (1H, d, J = 9.3 Hz), 2.91 (1H, m), 2.18 (3H, d, J = 7.2 Hz), 1.91-1.70 (5H, m), 1.43-1.20
(5H, m) ; 13C NMR (75 MHz, CDCl3) ; δ = 144.1 (CH), 138.7 (2 × C), 132.8 (CH), 128.5 (4
× CH), 127.5 (2 × CH), 126.2 (2 × CH), 126.1 (2 × CH), 125.1 (C), 122.2 (C), 93.4 (C), 92.3
(C), 40.7 (CH), 32.7 (2 × CH2), 26.2 (CH2), 26.0 (2 × CH2), 17.2 (CH3) ; HRMS (ESI) :
calcd for C25H26Na [M + Na]+: 349.1927; found 349.1922 ; IR (ATR) : ν = 3028, 2923, 1598,
1493, 1447, 758, 692 cm-1.
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((1E,5E)-1-(4-Methoxyphenyl)hepta-1,5-dien-3-yne-2,5-diyl)bis(trimethylsilane) (3e)
Following general procedure C on [3]-cumulenol 1e in CH2Cl2 (20 mL), the dienyne 3e was
obtained after flash chromatography on silica gel (n-Pentane/EtOAc, 98/2) as a yellow oil
corresponding to an inseparable mixture with furan 2e (0.173 g, 0.55 mmol, 55 % with a ratio
2e/3e of 50/50).
1H NMR (400 MHz, CDCl3) : δ = 7 .99 (2H, d, J = 8.4 Hz), 6.87 (2H, d, J = 8.4 Hz), 6.73
(1H, s), 6.23 (1H, q, J = 6.6 Hz), 3.83 (1H, s), 2.04 (3H, d, J = 6.8 Hz), 0.27 (9H, s), 0.21 (9H,
s) ; 13C NMR (75 MHz, CDCl3) ; δ = 159.6 (C), 144.4 (CH), 141.7 (CH), 131.3 (C), 130.4 (2
× CH), 126.7 (C), 121.9 (C), 113.6 (2 × CH), 100.2 (C), 98.4 (C), 55.4 (CH3), 18.6 (CH3), ‒
1.53 (6 × CH3). 1H and 13C NMR data matched those reported in the literature. [2]
((1E,5E)-1-(4-Nitrophenyl)hepta-1,5-dien-3-yne-2,5-diyl)bis(trimethylsilane) (3f)
Following general procedure B on [3]-cumulenol 1f in CH2Cl2 (20 mL), the dienyne 3f was
obtained after flash chromatography on silica gel (n-Pentane to n-Pentane/EtOAc, 98/2) as a
yellow oil corresponding to a mixture with furan 2f (0.170 g, 0.52 mmol, 52 % with a ratio
3f/2f of 38/62).
1H NMR (400 MHz, CDCl3) : δ = 8.20-8.15 (2H, m), 8.14-8.08 (2H, m), 6.81 (1H, s), 6.28
(1H, q, J = 6.6 Hz), 2.01 (3H, d, J = 6.6 Hz), 0.29 (9H, s), 0.19 (9H, s) ; 13C NMR (100 MHz,
CDCl3) : δ = 146.7 (C), 145.8 (CH), 143.8 (C), 139.0 (CH), 131.6 (C), 129.1 (2 × CH), 126.1
(C), 123.6 (2 × CH), 104.3 (C), 97.4 (C), 18.7 (CH3), ‒0.2 (3 × CH3), ‒0.2 (3 × CH3). 1H and
13C NMR data matched those reported in the literature. [2]
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((1E,5E)-1-Cyclohexylhepta-1,5-dien-3-yne-2,5-diyl)bis(trimethylsilane) (3g)
Following general procedure B on [3]-cumulenol 1g in CH2Cl2 (20 mL), the dienyne 3g was
obtained after flash chromatography on silica gel (n-Pentane to n-Pentane/EtOAc, 98/2) as a
yellowish oil corresponding to a mixture with furan 2g (0.198 g, 0.69 mmol, 69 % with a ratio
3g/2g of 77/23).
1H NMR (400 MHz, CDCl3) : δ = 6.16 (1H, q, J = 6.5 Hz), 5.89 (1H, d, J = 8.4 Hz), 2.74
(1H, m), 1.98 (3H, d, J = 6.4 Hz), 1.75-1.63 (5H, m), 1.36-1.03 (5H, m), 0.16 (9H, s), 0.15
13
(9H, s) ; C NMR (75 MHz, CDCl3) : δ = 155.4 (CH), 144.0 (CH), 126.6 (C), 123.1 (C),
97.2 (C), 95.7 (C), 41.6 (CH), 32.4 (2 × CH2), 26.3 (CH2), 26.1 (2 × CH2), 18.4 (CH3), ‒ 1.6
(CH3), ‒ 1.7 (CH3) ; HRMS (ESI) : calcd for C19H34KSi2 [M + K]+: 357.1831; found
357.1829 ; IR (ATR) : ν = 2924, 1572, 1246, 834, 752 cm-1.
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4. Spectral Data
(E)-1-(4-Methoxyphenyl)-2,5-diphenylhepta-2,3,4-trien-1-ol (1b)
17