Gold(i)-catalyzed 1,4- And/or 1,5-heteroaryl migration reactions through regiocontrolled cyclizations

Article abstract of DOI:10.1002/chem.201405190

Gold(I)-catalyzed regioselective cycloisomerizations of furan-ynes have been described. The reaction provides a concise access to stereodefined trisubstituted alkenes by endo cyclization with concomitant 1,5-migration of the furanyl group in the presence of unactivated 3 ? molecular sieves. In the absence of molecular sieves, indene products are generated by exo cyclization, followed by 1,4-furanyl migration/cyclization. The scope for 1,5-migrations can be extended to other heterocycles, such as benzofurans, thiophenes, and pyrroles.

Full text of DOI:10.1002/chem.201405190

DOI: 10.1002/chem.201405190
Communication
&
Organic Synthesis
Gold(I)-Catalyzed 1,4- and/or 1,5-Heteroaryl Migration Reactions
through Regiocontrolled Cyclizations
Chengyu Wang,[a, b] Xin Xie,[a] Jun Liu,[a] Yuanhong Liu,*[a] and Yuxue Li*[a]
also been reported.[4] However, the selective and controllable
Abstract: Gold(I)-catalyzed regioselective cycloisomeriza-
exo and/or endo cyclizations on the same substrate have not
tions of furan-ynes have been described. The reaction pro-
been reported yet in the reactions of furan-ynes.[5] Recently, we
vides a concise access to stereodefined trisubstituted al-
have developed a gold-catalyzed synthesis of 1-naphthol deriv-
kenes by endo cyclization with concomitant 1,5-migration
atives from benzene-tethered furan-ynes bearing a silyloxy or
of the furanyl group in the presence of unactivated 3ꢀ
allyloxy group at the a-position of the furan ring[3f]
molecular sieves. In the absence of molecular sieves,
(Scheme 1b). The reaction proceeds through the formation of
indene products are generated by exo cyclization, fol-
a cationic intermediate B or a cyclopropyl gold carbenoid, fol-
lowed by 1,4-furanyl migration/cyclization. The scope for
lowed by ring-opening of the furan ring and aromatization by
1,5-migrations can be extended to other heterocycles,
elimination of a proton at the benzylic position. Inspired by
such as benzofurans, thiophenes, and pyrroles.
these intriguing results, we wondered what would happen
using the furan-ynes 1 incorporated with a quaternary carbon
center at the benzylic position (R2 ¼H), since the aromatization
Furan frameworks widely occur
in natural products and serve as
useful and versatile synthetic in-
termediates in organic synthe-
sis.[1] Recent achievements in
gold-catalyzed intramolecular cy-
cloisomerizations of furan-ynes
has proved them to be valuable
tools for the construction of
complex molecules. Generally,
two types of cyclization, exo[2]
and endo cyclizations,[3] are in-
volved in the reaction system,
which depends on the nature of
the catalysts and the alkyne sub-
stituents. Usually, furan under-
goes exo cyclizations with termi-
nal alkynes, whereas it prefers
endo cyclizations with internal
alkynes, as exemplified in
Scheme 1a,b. In addition, gold-
catalyzed a-functionalization of
furans by b-tethered alkynes has
of the corresponding gold carbenoid intermediate (type C)
Scheme 1. Possible transformations of furan-ynes in the presence of gold catalyst.
could be completely inhibited due to the absence of proton
(Scheme 1c). We are, therefore, quite interested in exploring
new reaction patterns using these substrates. During this
study, we found that exo or endo cyclization could be selective-
ly achieved by the control of the reaction conditions. Herein,
we report our success on gold-catalyzed cycloisomerizations of
a tertiary silyl ether derivative of furan-ynes 1, which resulted
in the formation of trisubstituted alkenes 2 in the presence of
unactivated 3ꢀ molecular sieves with high stereoselectivity. Re-
markably, a novel 1,5-migration of the furan ring from the alco-
holic position to the alkyne terminus with a concomitant for-
mation of a ketone functionality was observed during the pro-
[a] Dr. C. Wang, X. Xie, Dr. J. Liu, Prof. Y. Liu, Prof. Y. Li
State Key Laboratory of Organometallic Chemistry
Shanghai Institute of Organic Chemistry
Chinese Academy of Sciences, 345 Lingling Lu
Shanghai 200032 (P. R. China)
E-mail: liyuxue@mail.sioc.ac.cn
yhliu@mail.sioc.ac.cn
[b] Dr. C. Wang
Department of Chemistry, East China Normal University
3663 North Zhongshan Road, Shanghai, 200062 (P. R. China)
Supporting information for this article is available on the WWW under
http://dx.doi.org/10.1002/chem.201705190.
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cess. Interestingly, in the absence of molecular sieves, exo cycli-
zation occurred preferentially, leading to the formation of 3-(2-
furanyl)-1H-indenes 3 by 1,4-furanyl migration.[6] It should be
noted that while 1,2- and 1,3-shifts are well-established in or-
ganic synthesis, migrations over a larger distance are still quite
rare. Although 1,4- and 1,5-aryl migrations have been prece-
dented,[7,8] most of these migrations proceed under radical
conditions[7] or promoted by acids,[8] whereas transition-metal-
catalyzed migrations are quite limited.
fluenced the reaction pathway, in which alkene 2a was formed
in 77% yield (entry 3). A catalytic amount of Ph2SO was also ef-
fective to give 2a selectively in 75% yield (entry 4). Further op-
timization indicated that the additive of molecular sieves could
also afford 2a as the major product. Thus, in the presence of
activated 3ꢀ molecular sieves, 66% of 2a could be formed
after stirring the reaction mixture for 16 h (entry 5). To our de-
light, the use of unactivated 3ꢀ molecular sieves (commercial
powdered 3ꢀ molecular sieves without activation before use)
not only further improved the yield of 2a to 88%, but also sig-
nificantly enhanced the reaction rate, as a complete conversion
was observed within 3 h (entry 6). The highest yield of 2a
(98%) was achieved by adding both unactivated 3ꢀ molecular
sieves and 0.2 equivalents Ph2SO (entry 7). The reaction could
also be performed in THF or CH2Cl2 to provide high yields (92–
95%) of 2a (entries 8–9). As expected, AgSbF6 alone did not
catalyze the reaction (entry 11). Other gold(I) complexes, such
as [Au(PPh3)]OTf, [Au(PPh3)]SbF6, and [Au(PPh3)]NTf2 were less
or not effective for this transformation (entries 12–14). Striking-
ly, the above results clearly indicated that a 1,4- or 1,5-furanyl
migration from the benzylic position to the alkyne moiety oc-
curred during the catalytic process.
The requisite substrates of TMS-protected (o-alkynyl)phenyl
(2-furyl)carbinols 1 were easily accessible through addition of
furanyllithium reagents to o-(alkynyl)phenyl ketones, or addi-
tion of the corresponding Grignard reagents to o-(alkynyl)-
phenyl furanyl ketones,[9] followed by protection with TMSCl.
We chose furan-yne 1a as a model substrate to explore the
new reaction pathways. The initial attempt employing 5 mol%
of cationic gold complex [Au(Johnphos)(MeCN)]SbF6 (A) as the
catalyst in a sealed tube[10] in toluene at room temperature for
1.5 h afforded 9% of an o-(alkenyl)phenyl ethanone 2a as
a single geometric isomer, along with 80% of indene 3a[6b]
(Table 1, entry 1). It should be noted that the Rf value of 3a
was the same with that of 1a on TLC analysis. In the presence
of 2.0 equivalents of water, only 8% of 2a was formed, along
with unreacted 1a and some undefined byproducts, which in-
dicated that the reaction is highly sensitive to water (entry 2).
Interestingly, addition of 2.0 equivalents of Ph2SO markedly in-
Next, we chose the reaction conditions shown in Table 1,
entry 7, to examine the scope for the formation of the alkene
products 2. As illustrated in Table 2, the method was applicable
to a wide range of suitably substituted 1,4-furan-ynes to fur-
nish the corresponding trisubsti-
tuted alkenes with excellent con-
trol of the olefin geometry. The
Table 1. Optimization studies for gold-catalyzed furanyl migration reactions.
substituent effects on the alkyne
terminus (R1) were first investi-
gated. The reaction tolerated
both electron-deficient and -rich
aromatic rings, and the yields of
the corresponding alkenes 2b–d
were in general between 79–
91%. The reaction of 1e contain-
ing a coordinative sulfur-contain-
ing thienyl group as R1 proceed-
ed without a problem to provide
2e in a high yield of 93%, which
indicated that the catalyst did
not get deactivated. A cyclohex-
enyl-substituted alkyne was also
compatible in this migration re-
action, furnishing 2 f in 66%
yield. The reaction with alkyl
substituted alkynes, such as cy-
clopropyl or n-butyl-substituted
alkynes, required a longer reac-
tion time at room temperature
(2g and 2h). However, perform-
ing the reaction at a higher tem-
perature of 508C could reduce
the reaction time to 2–4 h. Vary-
ing the substituent at the ben-
zylic position with an aryl group
Entry
Catalyst
[5 mol%]
MS
[ꢀ]
Ph2SO
[n equiv]
Solvent
t
[h]
Yield [%][a]
of 1a
Yield [%][a]
of 2a
Yield [%][a]
of 3a
1[b]
2[c]
3
4
5[d]
6[e]
7[e]
8[e]
9[e]
10[e]
11[e]
12[e]
13[e]
14[e]
A
A
A
A
A
A
A
A
–
–
–
–
3
3
3
3
3
3
3
3
3
3
–
–
2.0
0.2
–
toluene
toluene
toluene
toluene
toluene
toluene
toluene
THF
1.5
3
3
–
68
7
–
–
–
–
–
–
92
94
6
63
–
9 (7)
8
80 (74)
–
–
–
10
–
–
–
–
–
77
75
66
88
98 (89)
95
92
–
–
–
15
34
6
16
3
–
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.2
3
3
3
6
6
6
6
6
A
A
CH2Cl2
CH3CN
toluene
toluene
toluene
toluene
AgSbF6
–
–
–
–
[Au(PPh3)]OTf
[Au(PPh3)]SbF6
[Au(PPh3)]NTf2
[a] 0.3 mmol scale. [Substrate]=0.1m. All yields are NMR yields using CH2Br2 as the internal standard. Isolated
yields are shown in parentheses. [b] In a sealed tube. [c] 2.0 equiv H2O was added. [d] 70 mg activated molecu-
lar sieve was added. [e] 70 mg unactivated molecular sieve was added.
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Table 2. Gold-catalyzed cycloisomerization of furan-ynes to trisubstituted
alkenes.[a]
Table 3. Gold-catalyzed 1,5-migration of various heteroarenes.[a]
Entry
Substrate
Product/time/yield
1
2
3
4,5
6
7
[a] Isolated yields. [b] 508C.
[a] Unless noted, all the reactions were carried out using 5 mol% cata-
lyst A and 20 mol% diphenyl sulfoxide in the presence of unactivated 3ꢀ
molecular sieves at 808C in toluene. [b] Room temperature. [c] 5 mol%
catalyst A, 4.0 equiv diphenyl sulfoxide, 808C. [d] 5 mol% catalyst A,
2.0 equiv diphenyl sulfoxide, room temperature. [e] 5 mol% catalyst A,
2.0 equiv diphenyl sulfoxide, 808C.
in the place of a methyl group did not exert any influence on
the product yields, and the desired products 2i and 2j were
obtained in 88 and 71% yields, respectively, with exclusive mi-
gration of the furanyl group. The presence of a methyl or
phenyl group on the furan ring also led to efficient formation
of 2k and 2l. Substrates with a ꢀF, ꢀCl, or ꢀOMe group on the
parent phenyl ring were also well suited, giving the corre-
sponding alkene 2m–o in 78–81% yields.
Encouraged by these results, we next examined the migra-
tion reactions of other heterocyclic systems. As illustrated in
Table 3, this migration appeared to be quite general with vari-
ous heterocyclic cores. Benzofuran (Table 3, entries 1–2), thio-
phene (entries 3–5), and pyrrole rings (entries 6–7), all migrate
smoothly, producing the corresponding alkenes in moderate
to good yields, and also with excellent stereoselectivity. Com-
pared with the migration of furan rings, these reactions usually
proceeded with longer reaction times at room temperature
(entry 1) or under higher reaction temperature (808C, en-
tries 2–5, and 7), which implied that migrations of these het-
erocycles are less facile than that of furan rings. Interestingly,
benzofuran-tethered substrate 6 derived from a secondary al-
cohol also worked efficiently to afford the expected migration
product 7 in 73% yield, which indicated that there is no re-
quirement of the quaternary carbon center in the benzofuran
system (entry 2). The structures of compounds 2a, 5, 9, and 17
were unambiguously confirmed by X-ray crystal analysis.[11]
We also explored the reaction scope for the formation of in-
denes 3 by 1,4-furanyl migration. To avoid water contamina-
tion, all the reactions were carried out in sealed tube. As
shown in Table 4, various furan-ynes 1 were transformed into
the corresponding indenes 3b–i[11] in reasonable to good
yields of 69–93%. Both of the aryl or alkyl-substituted alkynes
underwent the reaction smoothly under anhydrous conditions.
However, replacement of the furan group to a 2-thienyl ring in
substrate 1 could not afford a clean reaction.
To reveal the reaction mechanism, DFT[12] studies have been
performed with the Gaussian 09 program[13] using the
PBE1PBE[14] method. Recent test calculations show that PBE0 is
one of the best functionals for the calculation of gold com-
plexes.[15] For C, H, O, Si, and P, the 6-311+G** basis set was
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slightly longer than that in free 1a (1.211 ꢀ) due to the activa-
tion. Then the p-electron of the double bond in the furan
moiety attacks the CꢁC triple bond, five transition states were
located.[17] We found that the transition states with the CꢀO
bond of the furan moiety in the equatorial (e) position of the
newly formed ring are more favorable. In these transition
states, the large OTMS groups are all in the equatorial position.
As shown in path a, in the best attacking mode TS-C2-
endo-e (9.7 kcalmolꢀ1), the C2 carbon atom of the furan ring
attacks the triple bond in a 6-endo-dig manner. Subsequently,
Table 4. Gold-catalyzed cycloisomerization of furan-ynes to indenes.[a]
the ring-opening transition-state TS-CC-Break (6.2 kcalmolꢀ1
)
results in re-aromatization of the furan ring and affords oxo-
nium ion INT-CC-Break (ꢀ8.7 kcalmolꢀ1). A similar CꢀC bond
cleavage in the gold-catalyzed reactions of furan-ynes has also
been observed by Hashmi et al.[6] The presence of unactivated
3 ꢀ molecular sieves can present
a basic environment
(pH 9.45)[18] and accelerate the desilylation. Calculations indi-
cate that removal of the TMS group in INT-CC-Break by OHꢀ
anion is nearly barrierless, leading to the product alkene 2a
and regenerating the cationic gold catalyst.[17] In addition, the
possible concerted fragmentation process promoted by the
H2O molecule was excluded by a relaxed potential-energy sur-
face scan.[17] The organogold intermediate might be quenched
by water contained in molecular sieves. Unlike the results by
addition of water to the system as mentioned in Table 1, the
use of unactivated molecular sieves could afford cleaner re-
sults. The results might be attributed to the lower water con-
centration in the latter case. The fate of Ph2SO was not clear
yet, it may stabilize the cationic intermediates formed during
the process.
[a] Isolated yields.
used; for Au, the SDD basis set with an Effective Core Potential
(ECP)[16] was used. Harmonic vibration frequency calculations
were carried out and the optimized structures are all shown to
be either minima (with no imaginary frequency) or transition
states (with one imaginary frequency). Substrate 1a and the
{Au(Me3P)}+ catalyst were used in the calculation models.
As shown in Scheme 2, the gold catalyst and substrate 1a
form complex R, in which the CꢁC triple bond is 1.237 ꢀ,
Scheme 2. Calculated reaction pathways for substrate 1a. The selected bond lengths are in ꢀ, and the relative free energies (DG) are in kcalmolꢀ1. Selected
NPA atomic charges and bond angles are given. Calculated at the PBE1PBE/6-311+G**/SDD level.
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117, 2858; f) A. S. K. Hashmi, P. Haufe, C. Schmid, A. R. Nass, W. Frey,
Chem. Eur. J. 2006, 12, 5376; g) A. S. K. Hashmi, M. C. Blanco, E. Kurpe-
When there is no base in the reaction system, the cyclization
of INT-CC-Break over TS-4-Cyc (11.8 kcalmolꢀ1) yields a thermo-
dynamically unstable product INT-4-Cyc (ꢀ5.1 kcalmolꢀ1). A
more favorable pathway is the reverse reaction, regenerating
the reactant complex R, then along path b forming the cy-
clized intermediate INT-exo-e (0.6 kcalmolꢀ1) over transition-
state TS-C2-exo-e (11.2 kcalmolꢀ1). Subsequently, the CꢀC
bond break by TS-CC-Break’ (6.3 kcalmolꢀ1) leads to intermedi-
ate INT-CC-Break’ (ꢀ4.6 kcalmolꢀ1), the cyclization of which
leads to product 3a-P (ꢀ26.9 kcalmolꢀ1). This process is similar
to that reported for Petasis–Ferrier rearrangement.[19]
´
jovic, W. Frey, J. W. Bats, Adv. Synth. Catal. 2006, 348, 709; h) A. S. K.
Hashmi, M. Rudolph, J. W. Bats, W. Frey, F. Rominger, T. Oeser, Chem. Eur.
J. 2008, 14, 6672; i) A. S. K. Hashmi, M. Rudolph, H. Siehl, M. Tanaka,
J. W. Bats, W. Frey, Chem. Eur. J. 2008, 14, 3703; j) A. S. K. Hashmi, S. Pan-
kajakshan, M. Rudolph, E. Enns, T. Bander, F. Rominger, W. Frey, Adv.
Synth. Catal. 2009, 351, 2855; k) A. S. K. Hashmi, M. Wçlfle, F. Ata, W.
Frey, F. Rominger, Synthesis 2010, 2297.
[3] a) Y. Chen, Y. Lu, G. Li, Y. Liu, Org. Lett. 2009, 11, 3838; b) A. S. K. Hashmi,
´
M. Rudolph, J. Huck, W. Frey, J. W. Bats, M. Hamzic, Angew. Chem. Int.
Ed. 2009, 48, 5848; Angew. Chem. 2009, 121, 5962; c) Y. Chen, G. Li, Y.
Liu, Adv. Synth. Catal. 2011, 353, 392; d) Y. Chen, Y. Liu, J. Org. Chem.
2011, 76, 5274; e) A. S. K. Hashmi, W. Yang, F. Rominger, Angew. Chem.
Int. Ed. 2011, 50, 5762; Angew. Chem. 2011, 123, 5882; f) C. Wang, Y.
Chen, X. Xie, J. Liu, Y. Liu, J. Org. Chem. 2012, 77, 1915; g) A. S. K.
Hashmi, W. Yang, F. Rominger, Chem. Eur. J. 2012, 18, 6576; h) N. Sun, X.
Xie, Y. Liu, Chem. Eur. J. 2014, 20, 7514; i) Y. Chen, L. Wang, N. Sun, X.
Xie, X. Zhou, H. Chen, Y. Li, Y. Liu, Chem. Eur. J. 2014, 20, 12015.
[4] a) R. S. Menon, M. G. Banwell, Org. Biomol. Chem. 2010, 8, 5483; b) Z.
Dong, C. H. Liu, Y. Wang, M. Lin, Z. X. Yu, Angew. Chem. Int. Ed. 2013, 52,
14157; Angew. Chem. 2013, 125, 14407.
[5] For regioselective and controllable cyclization of pyrrole- or indole-ynes
under different catalysts, see: a) S. G. Modha, A. Kumar, D. D. Vachhani,
S. K. Sharma, V. S. Parmar, E. V. Van der Eycken, Chem. Commun. 2012,
48, 10916; b) A. Kumar, Z. Li, S. K. Sharma, V. S. Parmar, E. V. Van der
Eycken, Chem. Commun. 2013, 49, 6803; c) A. Kumar, D. D. Vachhani,
S. G. Modha, S. K. Sharma, V. S. Parmar, E. V. van der Eycken, Synthesis
2013, 45, 2571.
In DFT studies on the gold-catalyzed a-functionalization of
furans by b-tethered alkynes,[4b] the selectivity of 7-endo and
6-exo attacks determined by the electrophilicity of carbon
atoms of the CꢁC triple bond. However, as shown in
Scheme 2, TS-C2-exo-e is less favorable though C2 in R is more
electrophilic.[20] The bond angles A1 and A2 in R are 122.5 and
123.28, respectively. In TS-C2-exo-e these two angles are de-
creased by 5.8 and 7.28, respectively. However, in TS-C2-
endo-e these two angles are only decreased by 1.0 and 1.18,
respectively. Therefore, we propose that in this case the larger
strain energy required to form the benzo five-membered ring
may be important for the regioselectivity.
In conclusion, we have disclosed gold-catalyzed endo- or
exo-selective cyclizations on the same substrates of furan-ynes.
The reaction provides a concise access to stereodefined trisub-
stituted alkenes by endo cyclization with concomitant 1,5-mi-
gration of the furanyl group in the presence of unactivated 3ꢀ
molecular sieves. While in the absence of molecular sieves,
indene products were generated by exo cyclization followed
by 1,4-furanyl migration and cyclization. The scope for 1,5-mi-
grations can be extended to other heterocycles, such as ben-
zofurans, thiophenes, and pyrroles. Further extensions of this
chemistry are in progress.
[6] For gold-catalyzed cyclizations of furan-ynes accompanied by furanyl
migration, see: a) A. S. K. Hashmi, T. Hꢂffner, W. Yang, S. Pankajakshan, S.
Schꢂfer, L. Schultes, F. Rominger, W. Frey, Chem. Eur. J. 2012, 18, 10480;
for indene formation accompanied by furanyl migration, see: b) A. S. K.
Hashmi, J. Hofmann, S. Shi, A. Schꢃtz, M. Rudolph, C. Lothschꢃtz, M.
Wieteck, M. Bꢃhrle, M. Wçlfle, F. Rominger, Chem. Eur. J. 2013, 19, 382.
[7] For a review, see: a) A. Studer, M. Bossart, Tetrahedron 2001, 57, 9649,
and the references therein. For recent papers, see: b) A. Studer, M. Bos-
sart, T. Vasella, Org. Lett. 2000, 2, 985; c) K. Wakabayashi, H. Yorimitsu, H.
Shinokubo, K. Oshima, Org. Lett. 2000, 2, 1899; d) A. Gheorghe, B. Quic-
let-Sire, X. Vila, S. Z. Zard, Org. Lett. 2005, 7, 1653; e) S. Amrein, M. Bos-
sart, T. Vasella, A. Studer, J. Org. Chem. 2000, 65, 4281.
[8] a) J. W. Wilt, T. P. Malloy, J. Am. Chem. Soc. 1970, 92, 4747; b) J. W. Wilt,
T. P. Malloy, P. K. Mookerjee, D. R. Sullivan, J. Org. Chem. 1974, 39, 1327;
c) K. Tomooka, A. Nakazaki, T. Nakai, J. Am. Chem. Soc. 2000, 122, 408;
d) T. Khan, P. J. Skabara, S. J. Coles, M. B. Hursthouse, Chem. Commun.
2001, 369; e) A. Nakazaki, J. Usuki, K. Tomooka, Synlett 2008, 2064; f) L.
Wu, M. Shi, Y. Li, Chem. Eur. J. 2010, 16, 5163.
Acknowledgements
We thank the National Natural Science Foundation of China
(Grant Nos. 21125210, 21372244, 21172248, 21121062), Chinese
Academy of Science, and the Major State Basic Research Devel-
opment Program (Grant No. 2011CB808700) for financial
support.
[9] Y. Chen, L. Wang, Y. Liu, Y. Li, Chem. Eur. J. 2011, 17, 12582.
[10] We found that if the reaction was carried out under the conditions con-
taminated with water, the yield of 2a could be increased.
[11] CCDC-915008 (2a), -1023011 (3d), -915006 (5), -915009 (9), and -915007
(17) contain the supplementary crystallographic data for this paper.
These data can be obtained free of charge from The Cambridge Crystal-
lographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
[12] a) P. Hohenberg, W. Kohn, Phys. Rev. 1964, 136, B864–B871; b) W. Kohn,
L. J. Sham, Phys. Rev. 1965, 140, A1133–A1138.
Keywords: alkenes · furans · gold catalysis · migration ·
stereoselectivity
[13] M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb, J. R.
Cheeseman, G. Scalmani, V. Barone, B. Mennucci, G. A. Petersson, H. Na-
katsuji, M. Caricato, X. Li, H. P. Hratchian, A. F. Izmaylov, J. Bloino, G.
Zheng, J. L. Sonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Ha-
segawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven,
A., Jr., Montgomery, J. E. Peralta, F. Ogliaro, M. Bearpark, J. J. Heyd, E.
Brothers, K. N. Kudin, V. N. Staroverov, R. Kobayashi, J. Normand, K. Ra-
ghavachari, A. Rendell, J. C. Burant, S. S. Iyengar, J. Tomasi, M. Cossi, N.
Rega, J. M. Millam, M. Klene, J. E. Knox, J. B. Cross, V. Bakken, C. Adamo,
J. Jaramillo, R. Gomperts, R. E. Stratmann, O. Yazyev, A. J. Austin, R.
Cammi, C. Pomelli, J. W. Ochterski, R. L. Martin, K. Morokuma, V. G. Zakr-
zewski, G. A. Voth, P. Salvador, J. J. Dannenberg, S. Dapprich, A. D. Dan-
iels, O. Farkas, J. B. Foresman, J. V. Ortiz, J. Cioslowski, D. J. Fox, Gaussian
09, Revision A.02, Gaussian, Inc., Wallingford, CT, 2009.
[1] a) B. H. Lipshutz, Chem. Rev. 1986, 86, 795; b) H. Heaney, J. S. Ahn in
Comprehensive Heterocyclic Chemistry II, Vol. 2 (Eds.: A. R. Katritzky, C. W.
Rees, E. F. V. Scriven), Pergamon Press, Oxford, 1996, pp. 297–350;
c) J. A. Joule, K. Mills, Heterocyclic Chemistry, 5th ed., Wiley-Blackwell,
Hoboken, 2010, pp. 347–368.
[2] a) A. S. K. Hashmi, T. M. Frost, J. W. Bats, J. Am. Chem. Soc. 2000, 122,
11553; b) A. S. K. Hashmi, T. M. Frost, J. W. Bats, Org. Lett. 2001, 3, 3769;
c) A. S. K. Hashmi, L. Ding, J. W. Bats, P. Fischer, W. Frey, Chem. Eur. J.
2003, 9, 4339; d) A. S. K. Hashmi, J. P. Weyrauch, M. Rudolph, E. Kurpe-
´
jovic, Angew. Chem. Int. Ed. 2004, 43, 6545; Angew. Chem. 2004, 116,
6707; e) A. S. K. Hashmi, M. Rudolph, J. P. Weyrauch, M. Wçlfle, W. Frey,
J. W. Bats, Angew. Chem. Int. Ed. 2005, 44, 2798; Angew. Chem. 2005,
Chem. Eur. J. 2014, 20, 1 – 7
www.chemeurj.org
5
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[14] a) J. P. Perdew, K. Burke, M. Ernzerhof, Phys. Rev. Lett. 1996, 77, 3865;
b) J. P. Perdew, K. Burke, M. Ernzerhof, Phys. Rev. Lett. 1997, 78, 1396.
[15] R. H. Kang, H. Chen, S. Shaik, J. N. Yao, J. Chem. Theory Comput. 2011, 7,
4002.
[19] a) N. A. Petasis, S. P. Lu, J. Am. Chem. Soc. 1995, 117, 6394; b) N. A. Peta-
sis, S. P. Lu, Tetrahedron Lett. 1996, 37, 141. For DFT study on the reac-
tion mechanism, see: c) G. J. Jiang, Y. Wang, Z. X. Yu, J. Org. Chem. 2013,
78, 6947.
[20] A. E. Reed, L. A. Curtiss, F. Weinhold, Chem. Rev. 1988, 88, 899.
[16] P. Fuentealba, H. Preuss, H. Stoll, L. von Szentpꢄly, Chem. Phys. Lett.
1982, 89, 418.
[17] See the Supporting Information for details.
Received: September 8, 2014
Published online on && &&, 0000
[18] Determined by pH meter using 10% aq. suspension.
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Communication
COMMUNICATION
&
Organic Synthesis
C. Wang, X. Xie, J. Liu, Y. Liu,* Y. Li*
&& – &&
Gold(I)-Catalyzed 1,4- and/or 1,5-
Heteroaryl Migration Reactions
through Regiocontrolled Cyclizations
Migrate to complex products: Gold(I)-
catalyzed regioselective cycloisomeriza-
tions of furan-ynes have been devel-
oped. In the presence of unactivated
3ꢀ molecular sieves, trisubstituted al-
kenes were provided stereoselectively
by endo cyclization with concomitant
1,5-migration of the furanyl group. In
the absence of molecular sieves, indene
products were generated by exo cycliza-
tion followed by 1,4-furanyl migration/
cyclization (see scheme).
Chem. Eur. J. 2014, 20, 1 – 7
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