Gold-catalyzed domino aminocyclization/1,3-sulfonyl migration of N-substituted N-sulfonyl-aminobut-3-yn-2-ols to 1-substituted 3-sulfonyl-1 H-pyrroles

Article abstract of DOI:10.1021/jo401083m

A method to prepare 1-substituted 3-sulfonyl-1H-pyrroles efficiently that relies on the gold(I)-catalyzed cycloisomerization of N-substituted N-sulfonyl-aminobut-3-yn-2-ols is described. The method was shown to be applicable to a broad range of 1,7-enyne alcohols containing electron-withdrawing, electron-donating, and sterically demanding substrate combinations. The mechanism is suggested to involve activation of the propargylic alcohol by the Au(I) catalyst, which causes the intramolecular nucleophilic addition of the sulfonamide unit to the alkyne moiety. The resulting nitrogen-containing heterocyclic intermediate undergoes dehydration and deaurative 1,3-sulfonyl migration, a process that remains rare in gold catalysis, to give the aromatic nitrogen-containing product.

Full text of DOI:10.1021/jo401083m

Article
pubs.acs.org/joc
Gold-Catalyzed Domino Aminocyclization/1,3-Sulfonyl Migration of
N‑Substituted N‑Sulfonyl-aminobut-3-yn-2-ols to 1‑Substituted
3‑Sulfonyl‑1H‑pyrroles
Wan Teng Teo, Weidong Rao, Ming Joo Koh, and Philip Wai Hong Chan*
Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University,
Singapore 637371, Singapore
S
* Supporting Information
ABSTRACT: A method to prepare 1-substituted 3-sulfonyl-1H-pyrroles efficiently that relies on the gold(I)-catalyzed
cycloisomerization of N-substituted N-sulfonyl-aminobut-3-yn-2-ols is described. The method was shown to be applicable to a
broad range of 1,7-enyne alcohols containing electron-withdrawing, electron-donating, and sterically demanding substrate
combinations. The mechanism is suggested to involve activation of the propargylic alcohol by the Au(I) catalyst, which causes
the intramolecular nucleophilic addition of the sulfonamide unit to the alkyne moiety. The resulting nitrogen-containing
heterocyclic intermediate undergoes dehydration and deaurative 1,3-sulfonyl migration, a process that remains rare in gold
catalysis, to give the aromatic nitrogen-containing product.
alkyne moiety to 4-sulfonyl-dihydropyrrole-oxides (Scheme 1,
eq 2).8 More recently, during the course of an ongoing program
examining the utility of gold catalysis in N-heterocyclic
synthesis,11 we found one further example of this type of
deaurative process (Scheme 2, pathway 1).9 With NHC−
gold(I) complex A shown in Figure 1 as the catalyst,12 3-tosyl
N-allyl pyrrole 2a and the 1,6-allene 3a were obtained in 20 and
29% yield, respectively, instead of the anticipated cyclobutane-
fused piperidine 4a from 1,7-enyne benzoate 1a. In a
continuation of these investigations, we reasoned that the
chemical yield of the potentially useful aromatic N-heterocyclic
adduct could be enhanced by the use of the corresponding 1,7-
enyne alcohol as the substrate and by identifying the
appropriate reaction conditions. Herein, we describe the details
of this study involving the Au(I)-catalyzed tandem amino-
cyclization/1,3-sulfonyl shift of N-substituted N-sulfonyl-
aminobut-3-yn-2-ols (Scheme 2, pathway 2). This process
provides a convenient and operationally straightforward route
to 1-substituted 3-sulfonyl-1H-pyrroles in good to excellent
yields for a wide variety of substrates.
INTRODUCTION
■
Gold-catalyzed organic transformations have received an
immense amount of attention over the years because of their
remarkable ability to deliver efficiently a diverse range of
synthetically useful complex molecules from simple and readily
accessible substrates.1−12 From a mechanistic viewpoint, the
reactions have generally relied on the gold-mediated activation
of the π bonds of alkenes, allenes, and alkynes to attack by a
nucleophile. This is then followed by protodeauration of the
resulting organogold species generated in situ in the final step
of the catalytic cycle to regenerate the metal catalyst and give
the product.1,2,9−12 Another approach to regenerate the metal
catalyst that has come under increasing scrutiny has been
carbodeauration, involving the substitution of the carbon−gold
bond by an allyl/α-alkoxy alkyl, iminium, or benzyl functional
group.3−6 The incorporation of a heteroatom into the product
at the electrophilic deauration step, by contrast, has been less
well investigated.7−10 This approach to regenerate the Lewis
acid catalyst has been reported only twice before in gold
catalysis, presumably because of the more favorable afore-
mentioned carbodeauration and protodeauration pathways. In
this context, a recent notable advance is that by Nakamura and
co-workers who showed that the deauration step involves 1,3-
sulfonyl migration in the gold-catalyzed cycloisomerization of o-
alkynyl-N-sulfonamides to the corresponding 3-sulfonylindole
derivatives (Scheme 1, eq 1).7,13 Following this seminal work,
Shin and co-workers reported a similar deaurative 1,3-sulfonyl
migration step to occur in the gold-catalyzed [3 + 2]
cycloadditions of N-sulfonyl hydroxylamines with a pendent
RESULTS AND DISCUSSION
■
To test the feasibility of our hypothesis, we choose 1b as the
model substrate to establish the reaction conditions (Table
1).15 This study revealed that treating 1b with 5 mol % of
Received: May 16, 2013
© XXXX American Chemical Society
A
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Scheme 1. Gold-Catalyzed Cycloisomerizations of Propargylic Substrates Involving a 1,3-Sulfonyl Migration Step
Scheme 2. Gold-Catalyzed Cycloisomerization of 1,7-Enyne Benzoates and Alcohols
Figure 1. Gold(I) complexes examined in this study.12,14
NHC−gold(I) complex A at 80 °C for 18 h gave the best
result, affording 1-allyl-2-benzyl-3,5-diphenyl-4-tosyl-1H-pyr-
role 2b in 70% yield (entry 1). The structure of the aromatic
nitrogen-containing heterocycle was confirmed by X-ray crystal
structure analysis.16 Lower product yields were obtained when
the reaction was carried out at room temperature or employed
THF or 1,2-dichloroethane in place of toluene as the solvent
(entries 2, 4, and 5). In the latter two control experiments,
trisubstituted pyrrole 5b was also furnished in low yields of 10
and 6% (entries 4 and 5), respectively. With 1,2-dichloroethane
as the solvent, a similar outcome was found when the reaction
was conducted with NHC−gold(I) complexes C−E,14 gold(I)
phosphine complexes F−H, and gold(I) phosphite complex I
shown in Figure 1 and with Ph3PAuNTf2 in place of A as the
catalyst (entries 7−13 and 15). In contrast, for the analogous
control experiments with NHC−gold(I) complex B shown in
Figure 1, (4-CF3Ph)3PAuCl/AgSbF6 or AuCl as the catalyst or
MeCN as the reaction solvent were found to be less effective
(entries 3, 6, 14, and 16). Subjecting 1b to these catalysts in
1,2-dichloroethane or NHC−gold(I) complex A with MeCN as
the solvent led to a variety of unidentifiable decomposition
1
products being detected by H NMR measurements of the
crude reaction mixtures. Likewise, AuBr3 and InBr3, reported to
promote the cycloisomerization of o-alkynyl-N-sulfonylanilines
to 3- and 5-sulfonyl substituted indoles,7 were found to result in
the recovery of 1b in 89% yield or a mixture of decomposition
products, respectively (entries 17 and 18). Control experiments
with AgSbF6, AgNTf2, and the Brønsted acids TfOH and
Tf2NH as the catalyst also led to the formation of a mixture of
decomposition products as well as provided evidence that the
cationic Au(I) complex is the active species (entries 19−22).
To define the scope of the present procedure, we next sought
to assess its generality for a series of N-substituted N-sulfonyl-
aminobut-3-yn-2-ols, and the results are summarized in Table 2.
Overall, the reaction conditions were found to be general, and a
variety of 3-sulfonyl-substituted pyrrole derivatives were
B
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a
Table 1. Optimization of the Reaction Conditions
yield (%)
entry
1
catalyst
solvent
2b
5b
6b
A
A
A
A
A
B
C
D
E
F
PhMe
70
b
2
PhMe
57
c
3
MeCN
4
THF
62
10
6
5
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
(CH2Cl)2
68
d
6
7
36
67
52
50
30
33
8
6
9
7
10
11
12
13
14
15
16
17
18
19
20
21
22
25
28
15
G
H
I
49
e
(4-CF3Ph)3PAuCl/AgSbF6
PPh3AuNTf2
AuCl
38
c
d
c
AuBr3
InBr3
AgSbF6
AgNTf2
TfOH
37
10
c
c
Tf2NH
a
b
c
All reactions conducted on the 0.2 mmol scale with 5 mol % of catalyst at 80 °C for 18 h. Reaction carried out at room temperature. Mixture of
d
unknown side products were furnished on the basis of 1H NMR analysis of the crude mixture. No reaction on the basis of TLC or 1H NMR analysis
of the crude mixture. Recovery of 1b in 66% yield.
e
afforded in 38−98% yield from corresponding starting alcohols
1c−v. Propargyl alcohols in which the carbinol carbon center is
occupied by a pendant phenyl group with an electron-donating
(1c) or electron-withdrawing (1d) substituent at the para
position gave corresponding products 2c and 2d in 56 and 41%
yield, respectively. Replacing the phenyl substituent at this
position with a 2-thiophenyl (1e) or Et (1f) moiety was found
to have no influence on the course of the reaction, affording 2e
and 2f in respective yields of 52 and 43%. Likewise, the
reactions of substrates with the CC bond substituted with an
aryl, thiophene, alkyl, or cycloalkyl group, as in 1g−l, were
found to be well tolerated and afforded corresponding products
2g−l in 59−93% yield. However, the presence of a terminal
alkyne moiety on the substrate (1m) was found to give
corresponding pyrrole adduct 2m in a lower yield of 45%.
Increasing the steric demand of the substituent at the amino
carbon (1n and 1o) was also found to play a role. In these
reactions, cycloisomerization of 1n, with a pendant Ph group at
the amino carbon center, gave 2n in 74% yield, whereas the
analogous reaction of 1o containing the more sterically bulky
iPr moiety at the same position afforded 2o in 38% yield.
Likewise, increasing the steric demand of the alkyl group (1p−
s) or decreasing the electron-donating ability of the sulfonyl
moiety (1t−v) on the amino center of the substrate was found
to give a similar outcome. Under standard conditions, the
corresponding N-methyl (2p), N-butyl (2q), N-benzyl (2r),
and N-cinnamyl (2s) protected products were obtained in 40−
98% yield. For reactions with N-(4-methoxyphenylsulfonyl)
(1t), N-(4-chlorophenylsulfonyl) (1u), and N-mesyl (1v)
protected substrates, corresponding 3-sulfonyl pyrrole adducts
2t−v were furnished in 67, 54, and 43% yields, respectively.
To demonstrate that the deaurative 1,3-sulfonyl migration
step proceeds in an intramolecular manner that leads to the
formation of the 3-sulfonyl-substituted pyrrole adduct, we next
examined the crossover experiment of 1 equiv of 1p with 1
equiv of 1v in the presence of 5 mol % A in toluene at 80 °C for
18 h (Scheme 3, eq 1). Under these conditions, both 2p and 2v
were afforded as the only products in respective yields of 42
and 58%, with the analysis of the crude reaction mixture by 1H
NMR spectroscopy and mass spectrometry showing no other
cyclic products being detected. Our findings that show the
near-quantitative recovery of starting materials for the reaction
of 5b with pTsCl exposed to 5 mol % of A under the standard
conditions described in Scheme 3, eq 2 led us to also posit that
an intermolecular deaurative sulfonylation step was unlikely.
Although speculative, the mechanism for the present Au(I)-
catalyzed 3-sulfonyl-pyrrole-forming reaction is outlined in
Scheme 4. This could involve the activation of the propargylic
alcohol through coordination of the metal catalyst with the
alkyne moiety of the adduct to give Au(I)-coordinated
intermediate A. As a result, this triggers the intramolecular
aminocyclization process involving anti addition of the N,N-
disubstituted amino moiety to the CC bond to provide vinyl
gold complex B. At this juncture, dehydration of this newly
C
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a
the substituents on the pyrrole ring and the migrating sulfonyl
moiety increase as a result of either of these functional groups
increasing. In the case of the observed trend when varying the
substitutent R1, this could be due to competition between the
alkyl and sulfonyl groups on the amine center to migrate as a
result of the ability of the former to stabilize a partial positive
charge as it increases in steric bulk and π conjugation. Similarly,
the lower product yields furnished upon going from substrates
containing a N-(4-tolylsulfonyl) or N-(4-methoxyphenylsulfon-
yl) to a N-(4-chlorophenylsulfonyl) protecting group would be
in good agreement with the typically lower migratory aptitudes
of less electron-rich moieties. However, the low product yield
obtained for the cycloisomerization of N-mesyl-protected
starting alcohol 1v could be due the competitive deprotonation
of the mesylate cation to form sulphene during the 1,3-
migration process.
Table 2. Cycloisomerization of 1c−v Catalyzed by A
CONCLUSIONS
■
We have demonstrated a gold(I)-catalyzed synthesis strategy
for the construction of 1-substituted 3-sulfonyl-1H-pyrroles
from N-substituted N-sulfonyl-amonibut-3-yn-2-ols. The re-
action was shown to be applicable to a diverse set of propargylic
alcohols and provided a number of new pyrrole-family
compounds for potential applications in medicinal chemistry.
Our studies suggest that the nitrogen-containing ring-forming
process likely involves dehydrative aminocyclization followed
by deaurative 1,3-sulfonyl migration. Efforts to explore the
synthesis applications of the present reaction are currently
underway and will be reported in due course.
a
All reactions were conducted on the 0.2 mmol scale with 5 mol % of
A in toluene at 80 °C for 18 h. The values in parentheses denote
product yields.
formed organogold intermediate might lead to the formation of
cationic pyrrole-gold adduct C and the generation of one
molecule of H2O (Scheme 4, path a). Subsequent 1,3-sulfonyl
migration of this putative species might then result in the
deauration and regeneration of the Lewis acid catalyst and
delivery of the product. Alternatively, vinyl gold complex B
could undergo the deaurative 1,3-sulfonyl migration process
first to give 2,3-dihydro-1H-pyrrol-3-ol adduct D that upon
dehydrative aromatization would provide 2 (Scheme 4, path b).
The formation of 5b under certain conditions described in
Table 1 could be due to a competing pathway in which
intermediates B or C undergoes protodeauration. The premise
that the deauration step involves 1,3-sulfonyl migration would
also be consistent with the gradual decrease in product yield as
the steric and electronic nature of the pendant group at the
amino carbon or amine center increases upon going from 1b →
1n → 1o and 1p → 1q → 1b → 1r → 1s or a less electron-
donating N-sulfonyl protecting group upon going from 1b or 1t
→ 1u. It might be anticipated that such a pathway would not be
expected to be as efficient because steric interactions between
EXPERIMENTAL SECTION
■
General Considerations. Unless otherwise stated, all reactions
were performed in oven-dried glassware under an argon atmosphere.
All reagents and starting materials were purchased from commercial
sources and used as received unless otherwise specified. Gold(I)
complexes A−D and F−I were purchased from commercial sources or
prepared following literature procedures.9,12 α-Tosylamino ketones S1
were prepared from the corresponding L-α-amino acids following
literature procedures.9 Analytical TLC was performed using a
precoated silica gel plate and was visualized with ultraviolet radiation
at 254 nm through staining with a potassium permanganate solution.
Flash chromatography was performed using silica gel and a gradient
solvent system (EtOAc/n-hexane as eluent). 1H and 13C NMR spectra
were recorded on a 300 or 400 MHz NMR spectrometer with
tetramethylsilane (TMS) as the internal standard. Chemical shifts were
reported in parts per million (ppm) with coupling constants reported
in Hertz (Hz). Multiplicities are given as s (singlet), br s (broad
singlet), d (doublet), t (triplet), dd (doublet of doublets), or m
(multiplet). The number of protons (n) for a given resonance is
indicated by nH. Infrared spectra were recorded on an FTIR
Scheme 3. Control Experiments with 1p, 1v, and 5b Catalyzed by A
D
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Scheme 4. Proposed Mechanism for the Au(I)-Catalyzed Cycloisomerization of 1
spectrometer. Solid samples were examined as a thin film between
NaCl salt plates. Low-resolution mass spectra were determined on a
mass spectrometer and reported in units of mass to charge (m/z).
High-resolution mass spectra (HRMS) were obtained on a LC/HRMS
TOF spectrometer using simultaneous electrospray ionization (ESI).
Procedure for the Synthesis of Gold(I) Complex E.14 To a
solution of IPrAuCl (150 mg, 0.24 mmol) in CH2Cl2 (2 mL) was
added a solution of AgPF6 (60.7 mg, 0.24 mmol) in CH2Cl2 (1 mL) at
room temperature. The mixture was stirred for 1 h, and the resulting
reaction mixture was filtered, washed with CH2Cl2 (2 × 4 mL), and
concentrated under reduced pressure. Diethyl ether (5 mL) was then
slowly added, which resulted in the immediate precipitation of a solid.
The precipitate was filtered, washed with diethyl ether (2 × 5 mL),
and dried under reduced pressure. This gave the title compound as a
light-pink, air-stable solid (129.5 mg, 78% yield): mp = 199−201 °C;
1H NMR (CDCl3, 400 MHz) δ 1.22 (d, 14H, J = 6.4 Hz), 1.31 (d,
mixture was concentrated under reduced pressure and purified by flash
column chromatography on silica gel (eluent: n-hexane/EtOAc = 6:1)
to afford product 2.
N-Allyl-N-(3-hydroxy-1,3,5-triphenylpent-4-yn-2-yl)-4-meth-
ylbenzenesulfonamide (1b).15 Colorless solid: yield 86%; 0.449 g;
mp = 155−157 °C; 1H NMR (CDCl3, 400 MHz) δ 2.32 (s, 3H), 2.85
(d, 1H, J = 14.1 Hz), 2.98 (d, 1H, J = 11.1 Hz), 3.61 (s, 1H), 4.31 (d,
1H, J = 6.0 Hz), 4.37 (d, 1H, J = 13.2 Hz), 4.89 (d, 1H, J = 9.2 Hz),
5.05 (d, 1H, J = 10.1 Hz), 5.16 (d, 1H, J = 17 Hz), 5.79−5.83 (m, 1H),
6.83 (d, 2H, J = 6.6 Hz), 6.94 (d, 2H, J = 7.7 Hz), 7.10−7.15 (m, 5H),
7.36−7.39 (m, 4H), 7.45 (t, 2H, J = 7.5 Hz), 7.53−7.55 (m, 2H), 7.89
(d, 2H, J = 7.6 Hz); 13C NMR (CDCl3, 100 MHz) δ 21.5, 34.3, 46.8,
69.6, 75.3, 89.0, 89.3, 117.3, 122.1, 126.3, 126.8, 127.9, 128.5, 128.55,
128.58, 129.0, 129.2, 131.7, 135.9, 136.9, 138.0, 142.9, 143.1; IR
(NaCl, neat) v 3412, 3021, 1599, 1325 cm−1; HRMS (ESI) [M + Na]+
calcd for C33H31NO3SNa, 544.1922; found, 544.1926.
N-Allyl-N-(3-hydroxy-1,5-diphenyl-3-(p-tolyl)pent-4-yn-2-
11H, J = 4.8 Hz), 2.47−2.51 (m, 4H), 7.26−7.31 (m, 6H), 7.50−7.52
(m, 2H); 13C NMR (CDCl3, 100 MHz) δ 24.1, 24.3, 28.8, 123.8,
124.4, 131.0, 133.6, 145.5; 31P NMR (161.98 MHz, CDCl3) δ −14.04
(t, 1J(19F−31P) = 980.0 Hz); HRMS (DART) calcd for C27H38N2OAu
(M+−POF2), 603.2650; found, 603.2632.
yl)-4-methylbenzenesulfonamide (1c). Yellow solid: yield 75%;
1
0.402 g; mp = 56−58 °C; H NMR (CDCl3, 400 MHz) δ 2.32 (s,
3H), 2.40 (s, 3H), 2.83 (d, 1H, J = 14.5 Hz), 2.96 (d, 1H, J = 11.6 Hz),
3.52 (s, 1H), 4.30 (d, 1H, J = 6.0 Hz), 4.37 (d, 1H, J = 13.6 Hz), 4.89
(d, 1H, J = 9.4 Hz), 5.04 (d, 1H, J = 10.1 Hz), 5.15 (d, 1H, J = 17.1
Hz), 5.79−5.82 (m, 1H), 6.85 (d, 2H, J = 6.9 Hz), 6.94 (d, 2H, J = 7.9
Hz), 7.09−7.16 (m, 4H), 7.25 (d, 3H, J = 7.8 Hz), 7.35−7.38 (m, 3H),
7.51−7.54 (m, 2H), 7.77 (d, 2H, J = 8.1 Hz); 13C NMR (CDCl3, 100
MHz) δ 21.2, 21.5, 34.4, 46.8, 69.6, 75.2, 89.2, 117.3, 122.2, 126.3,
126.7, 127.9, 128.5, 128.6, 129.0, 129.16, 129.24, 131.7, 136.0, 137.0,
138.1, 138.2, 140.3, 142.9; IR (NaCl, neat) v 3460, 3019, 1599, 1454
cm−1; HRMS (ESI) [M + Na]+ calcd for C34H33NO3SNa, 558.2079;
found, 558.2076.
General Procedure for the Preparation of 1b−v. To a round-
bottomed flask containing 4-methyl-N-(1,2-disubstituted)-
benzenesulfonamide9 (3.0 mmol) was added K2CO3 (9.0 mmol)
followed by dimethylformamide (10 mL). The corresponding allyl/
alkyl bromide or MeI (9.0 mmol) was then added, and the reaction
mixture was allowed to stir for 12−48 h at room temperature. On
completion, H2O (10 mL) and diethyl ether (10 mL) were
sequentially added to the reaction mixture. The aqueous layer was
extracted with ether (3 × 20 mL), and the organic layers were
combined, dried over MgSO4, and concentrated under reduced
pressure. The crude mixture was then purified by flash column
chromatography on silica gel (eluent: n-hexane/EtOAc = 6:1) to
afford the α-allylsulfonylamino ketone product, which was used
directly for the next step. To a solution of ethynylbenzene (3.0 mmol)
in THF (15 mL) was added LDA (2.0 M in THF, 1.5 mL, 3.0 mmol)
at −78 °C. The resulting solution was stirred for 1 h at −78 °C. The α-
allylsulfonylamino ketone (1 mmol) in THF (2 mL) was subsequently
added dropwise to the reaction mixture at −78 °C. The resulting
reaction mixture was slowly warmed to room temperature and stirred
for 16 h. On completion, the reaction mixture was quenched by the
addition of saturated NH4Cl (10 mL) and extracted with EtOAc (2 ×
30 mL). The combined organic layers were washed with brine (20
mL), dried over MgSO4, concentrated under reduced pressure, and
purified by flash column chromatography on silica gel (eluent: n-
hexane/EtOAc = 7:1) to afford the title compound.
N-Allyl-N-(3-(4-chlorophenyl)-3-hydroxy-1,5-diphenylpent-
4-yn-2-yl)-4-methylbenzenesulfonamide (1d). Yellow solid: yield
65%; 0.361 g; mp = 127−129 °C; 1H NMR (CDCl3, 400 MHz) δ 2.33
(s, 3H), 2.84 (d, 1H, J = 14.0), 2.97 (d, 1H, J = 11.1 Hz), 3.64 (s, 1H),
4.26 (d, 1H, J = 4.6 Hz), 4.34 (d, 1H, J = 12.9 Hz), 4.84 (d, 1H, J = 8.6
Hz), 5.06 (d, 1H, J = 10.0 Hz), 5.16 (d, 1H, J = 17.1 Hz), 5.70−5.90
(m, 1H), 6.85 (d, 2H, J = 6.4 Hz), 6.96 (d, 2H, J = 7.3 Hz), 7.08−7.17
(m, 5H), 7.38−7.40 (m, 5H), 7.51−7.53 (m, 2H), 7.80 (d, 2H, J = 8.4
Hz); 13C NMR (CDCl3, 100 MHz) δ 21.5, 34.4, 46.8, 69.4, 75.0, 88.6,
89.5, 117.5, 121.9, 126.4, 127.9, 128.4, 128.5, 128.6, 129.16, 129.2,
131.7, 134.3, 135.7, 136.7, 137.7, 141.7, 143.1; IR (NaCl, neat) v 3480,
3019, 1597, 1489 cm−1; HRMS (ESI) [M + Na]+ calcd for
C33H30ClNO3S, 578.1533; found, 578.1538.
N-Allyl-N-(3-hydroxy-1,5-diphenyl-3-(thiophen-2-yl)pent-4-
yn-2-yl)-4-methylbenzenesulfonamide (1e). Yellow solid: yield
72%; 0.380 g; mp = 129−131 °C; 1H NMR (CDCl3, 400 MHz) δ 2.33
(s, 3H), 2.96−3.04 (m, 2H), 3.78 (s, 1H), 4.30−4.36 (m, 2H), 4.91 (d,
1H, J = 7.6 Hz), 5.08 (d, 1H, J = 10.1 Hz), 5.18 d, 1H, J = 17.2 Hz),
5.70−5.86 (m, 1H), 6.91−6.97 (m, 4H), 7.03 (dd, 1H, J = 5.1, 3.6
Hz), 7.09−7.17 (m, 5H), 7.34−7.39 (m, 4H), 7.43 (dd, 1H, J = 3.5,
1.0 Hz), 7.52−7.54 (m, 2H); 13C NMR (CDCl3, 100 MHz) δ 21.5,
34.9, 46.8, 69.7, 72.7, 88.1, 88.6, 117.4, 121.9, 126.2, 126.3, 126.4,
General Experimental Procedure for NHC−Gold(I) Complex
A-Catalyzed Cycloisomerization of 1b−v. A two-neck round-
bottomed flask containing 1,7-enyne alcohol 1 (0.19 mmol) and
NHC−gold(I) complex A (0.01 mmol) was purged twice with argon
gas before toluene (2 mL) was added. The resulting reaction mixture
was then stirred at 80 °C for 18 h. On completion, the reaction
E
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Article
127.0, 127.9, 128.5, 128.6, 129.16, 129.21, 131.7, 136.0, 136.8, 137.9,
143.0, 148.3; IR (NaCl, neat) v 3429, 3019, 1599, 1493, 1090 cm−1;
HRMS (ESI) [M + Na]+ calcd for C31H29NO3S2Na, 550.1487; found,
550.1469.
3019, 1599, 1449 cm−1; HRMS (ESI) [M + H]+ calcd for
C31H36NO3S, 502.2416; found, 502.2421.
N-Allyl-N-(5-cyclopropyl-3-hydroxy-1,3-diphenylpent-4-yn-
2-yl)-4-methylbenzenesulfonamide (1k). Colorless solid: yield
1
86%; 0.418 g; mp = 105−107 °C; H NMR (CDCl3, 400 MHz) δ
N-Allyl-N-(3-ethyl-3-hydroxy-1,5-diphenylpent-4-yn-2-yl)-4-
methylbenzenesulfonamide (1f). Pale-yellow solid: yield 85%;
0.369 g; mp = 83−85 °C; 1H NMR (CDCl3, 400 MHz) δ 1.21 (t, 3H,
J = 7.3 Hz), 1.84−2.01 (m, 2H), 2.33 (s, 3H), 2.63 (s, 1H), 3.02 (dd,
1H, J = 14.4, 10.3 Hz), 3.32 (d, 1H, J = 12.6 Hz), 4.12 (dd, 1H, J =
16.1, 6.1 Hz), 4.22 (dd, 1H, J = 16.2, 5.0 Hz), 4.59 (d, 1H, J = 6.8 Hz),
3.57 (d, 1H, J = 10.1 Hz), 5.17 (d, 1H, J = 17.2 Hz), 5.79−5.85 (m,
1H), 6.46 (d, 2H, J = 7.6 Hz), 7.09−7.15 (m, 4H), 7.18−7.21 (m,
3H), 7.30−7.33 (m, 3H), 7.42−7.44 (m, 2H); 13C NMR (CDCl3, 100
MHz) δ 8.5, 21.5, 34.0, 35.4, 47.0, 67.2, 74.8, 86.8, 90.3, 117.5, 122.4,
126.4, 127.8, 128.4, 128.6, 129.2, 129.4, 131.7, 136.1, 137.0, 138.75,
142.8; IR (NaCl, neat) v 3524, 3019, 1599 cm−1; HRMS (ESI) [M +
H]+ calcd for C29H32NO3S, 474.2103; found, 474.2123.
0.77−0.81 (m, 2H), 0.83−0.88 (m, 2H), 1.39−1.43 (m, 1H), 2.31 (s,
3H), 2.71 (d, 1H, J = 14.0 Hz), 2.85 (d, 1H, J = 11.2 Hz), 3.36 (s, 1H),
4.22−4.31 (m, 2H), 4.76 (d, 1H, J = 9.2 Hz), 5.05 (d, 1H, J = 9.6 Hz),
5.18 (d, 1H, J = 17.2 Hz), 5.65−5.75 (m, 1H), 6.81 (d, 2H, J = 6.8
Hz), 6.93 (d, 2H, J = 7.8 Hz), 7.05−7.16 (m, 5H), 7.32−7.36 (m, 1H),
7.39−7.43 (m, 2H), 7.79 (d, 2H, J = 7.4 Hz); 13C NMR (CDCl3, 100
MHz) δ −0.4, 8.26, 8.28, 21.5, 34.3, 46.6, 69.4, 74.9, 75.2, 93.1, 116.9,
126.2, 126.8, 127.9, 128.2, 128.3, 128.4, 129.1, 129.2, 136.2, 137.0,
138.1, 142.8, 143.5; IR (NaCl, neat) v 3480, 3026, 1599, 1454 cm−1;
HRMS (ESI) [M + H]+ calcd for C30H32NO3S, 486.2103; found,
486.2102.
N-Allyl-N-((2S,3S)-5-(cyclohex-1-en-1-yl)-3-hydroxy-1,3-di-
phenylpent-4-yn-2-yl)-4-methylbenzenesulfonamide (1l). Yel-
N-Allyl-N-(3-hydroxy-1,3-diphenyl-5-(p-tolyl)pent-4-yn-2-
1
low solid: yield 80%; 0.421 g; mp = 117−119 °C; H NMR (CDCl3,
yl)-4-methylbenzenesulfonamide (1g). Yellow solid: yield 76%;
1
400 MHz) δ 1.61−1.70 (m, 4H), 2.13−2.15 (m, 2H), 2.20−2.22 (m,
2H), 2.32 (s, 3H), 2.75 (d, 1H, J = 14.4 Hz), 2.88 (d, 1H, J = 10.9 Hz),
3.41 (s, 1H), 4.26−4.28 (m, 2H), 4.82 (d, 1H, J = 9.0 Hz), 5.05 (d,
1H, J = 10.0 Hz), 5.17 (d, 1H, J = 17.2 Hz), 5.75−5.77 (m, 1H), 6.22−
6.24 (m, 1H), 6.82 (d, 2H, J = 7.0 Hz), 6.94 (d, 2H, J = 7.9 Hz), 7.08−
7.14 (m, 5H), 7.36 (t, 1H, J = 7.2 Hz), 7.42 (t, 2H, J = 7.8 Hz), 7.82
(d, 2H, J = 7.4 Hz); 13C NMR (CDCl3, 100 MHz) δ 21.5, 22.2, 25.7,
29.0, 34.4, 46.7, 69.5, 75.2, 86.2, 91.2, 117.1, 120.0, 126.2, 126.9, 127.9,
128.3, 128.4, 129.1, 129.2, 136.1, 137.2, 138.1, 142.8, 143.4; IR (NaCl,
neat) v 3400, 3019, 1599, 1449 cm−1; HRMS (ESI) [M + H]+ calcd
for C33H36NO3S, 526.2416; found, 526.2421.
0.407 g; mp = 116−118 °C; H NMR (CDCl3, 400 MHz) δ 2.32 (s,
3H), 2.38 (s, 3H), 2.84 (d, 1H, J = 13.7 Hz), 2.97 (d, 1H, J = 11.4 Hz),
3.58 (s, 1H), 4.31−4.36 (m, 2H), 4.89 (d, 1H, J = 8.5 Hz), 5.05 (d,
1H, J = 9.8 Hz), 5.16 (d, 1H, J = 16.9 Hz),5.65−5.81 (m, 1H), 6.83 (d,
2H, J = 5.4 Hz), 6.94 (d, 2H, J = 7.4 Hz), 7.10−7.19 (m, 7H), 7.37−
7.46 (m, 5H), 7.89 (d, 2H, J = 7.0 Hz); 13C NMR (CDCl3, 100 MHz)
δ 21.5, 21.6, 34.4, 46.7, 69.6, 75.4, 88.3, 89.5, 117.3, 119.1, 126.3,
126.9, 127.9, 128.4, 128.5, 129.16, 129.19, 129.3, 131.6, 136.0, 137.0,
138.0, 139.2, 142.9, 143.2; IR (NaCl, neat) v 3443, 3019, 1599, 1454
cm−1; HRMS (ESI) [M + H]+ calcd for C34H34NO3S, 536.2259;
found, 536.2249.
N-Allyl-N-(3-hydroxy-1,3-diphenylpent-4-yn-2-yl)-4-methyl-
N-Allyl-N-(5-(4-bromophenyl)-3-hydroxy-1,3-diphenylpent-
1
benzenesulfonamide (1m). Colorless oil: yield 73%; 0.325 g; H
4-yn-2-yl)-4-methylbenzenesulfonamide (1h). Yellow solid: yield
NMR (CDCl3, 400 MHz) δ 2.32 (s, 3H), 2.78 (d, 1H, J = 14.4 Hz),
2.91−2.98 (m, 2H), 3.61 (s, 1H), 4.27−4.29 (m, 2H), 4.80 (d, 1H, J =
9.6 Hz), 5.06 (d, 1H, J = 10 Hz), 5.19 (d, 1H, J = 17.2 Hz), 5.71−5.74
(m, 1H), 6.80 (d, 2H, J = 6.4 Hz), 6.93 (d, 2H, J = 8.0 Hz), 7.05−7.15
(m, 5H), 7.35−7.46 (m, 3H), 7.83 (d, 2H, J = 7.6 Hz); 13C NMR
(CDCl3, 100 MHz) δ 21.5, 34.2, 46.6, 74.9, 77.8, 83.7, 117.4, 126.3,
126.7, 127.9, 128.4, 128.5, 129.1, 135.7, 136.9, 137.9, 142.6, 142.9; IR
(NaCl, neat) v 3300, 3026, 1599, 1454 cm−1; HRMS (ESI) [M + H]+
calcd for C27H28NO3S, 446.1790; found, 446.1784.
1
72%; 0.432 g; mp = 64−66 °C; H NMR (CDCl3, 400 MHz) δ 2.31
(s, 3H), 2.84 (d, 1H, J = 14.0 Hz), 2.94 (d, 1H, J = 10.8 Hz), 3.65 (s,
1H), 4.25−4.36 (m, 2H), 4.88 (d, 1H, J = 8.6 Hz), 5.04 (d, 1H, J =
10.0 Hz), 5.14 (d, 1H, J = 16.8 Hz), 5.76−5.80 (m, 1H), 6.82 (d, 2H, J
= 6.5 Hz), 6.93 (d, 2H, J = 7.5 Hz), 7.08−7.17 (m, 5H), 7.37−7.40
(m, 3H), 7.42−7.52 (m, 4H), 7.86 (d, 2H, J = 7.5 Hz); 13C NMR
(CDCl3, 100 MHz) δ 21.5, 34.3, 46.7, 69.5, 75.5, 88.0, 90.2, 117.3,
121.0, 123.3, 126.3, 126.7, 127.9, 128.4, 128.6, 129.1, 129.2, 131.5,
131.8, 133.1, 135.9, 136.9, 142.9, 143.0; IR (NaCl, neat) v 3447, 3019,
1599, 1487, 754 cm−1; HRMS (ESI) [M + Na]+ calcd for
C33H30BrNO3SNa, 622.1027; found, 622.1012.
N-Allyl-N-(2-hydroxy-1,2,4-triphenylbut-3-yn-1-yl)-4-meth-
ylbenzenesulfonamide (1n). Colorless solid: yield 76%; 0.386 g;
mp = 117−119 °C; 1H NMR (CDCl3, 400 MHz) δ 2.29 (s, 3H), 3.99
(dd, 1H, J = 16.7, 5.9 Hz), 4.29 (dd, 1H, J = 16.7, 6.4 Hz), 5.07 (dd,
1H, J = 10.2, 1.2 Hz), 5.19 (dd, 1H, J = 1.4 Hz), (s, 1H), 5.79−5.90
(m, 1H), 7.00 (d, 2H, J = 8.1 Hz), 7.15−7.24 (m, 5H), 7.33−7.35 (m,
3H), 7.40−7.44 (m, 4H), 7.52−7.60(m, 5H); 13C NMR (CDCl3, 100
MHz) δ 21.4, 49.4, 70.4, 88.1, 91.2, 117.4, 122.4, 126.5, 127.8, 127.9,
127.96, 128.02, 128.4, 128.7, 129.1, 130.8, 131.9, 135.2, 136.4, 137.4,
142.4, 143.0; IR (NaCl, neat) v 3019, 1599, 1327 cm−1; HRMS (ESI)
[M + Na]+ calcd for C32H29NO3SNa, 530.1766; found, 530.1776.
N-Allyl-N-((3S,4S)-4-hydroxy-2-methyl-4,6-diphenylhex-5-
yn-3-yl)-4-methylbenzenesulfonamide (1o). Yellow solid: yield
74%; 0.350 g; mp = 101−103 °C; 1H NMR (CDCl3, 400 MHz) δ 0.50
(d, 3H, J = 6.6 Hz), 0.82 (d, 3H, J = 6.6 Hz), 2.26−2.28 (m, 1H), 2.41
(s, 3H), 3.03 (s, 1H), 4.25 (dd, 1H, J = 16.4, 5.6 Hz), 4.38 (d, 1H, J =
7.6 Hz), 4.44 (d, 1H, J = 9.8 Hz), 5.09 (dd, 1H, J = 10.1, 1.1 Hz), 5.24
(dd, 1H, J = 17.1, 1.1 Hz), 6.00−6.08 (m, 1H), 7.28 (d, 1H, J = 8 Hz),
7.32−7.43 (m, 6H), 7.48−7.51 (m, 2H), 7.82−7.88 (m, 4H); 13C
NMR (CDCl3, 100 MHz) δ 21.5, 21.6, 22.0, 29.7, 47.5, 72.5, 74.3,
88.8, 89.9, 117.8, 122.2, 127.0, 128.3, 128.4, 128.5, 128.6, 129.0, 129.3,
131.6, 135.8, 137.8, 143.3, 144.6; IR (NaCl, neat) v 3501, 3019, 1599,
1449 cm−1; HRMS (ESI) [M + Na]+ calcd for C29H31NO3SNa,
496.1922; found, 496.1925.
N-Allyl-N-(3-hydroxy-1,3-diphenyl-5-(thiophen-3-yl)pent-4-
yn-2-yl)-4-methylbenzenesulfonamide (1i). Yellow solid: yield
90%; 0.475 g; mp = 154−156 °C; 1H NMR (CDCl3, 400 MHz) δ 2.32
(s, 3H), 2.82 (d, 1H, J = 14.1 Hz), 2.95 (d, 1H, J = 11.2 Hz), 3.59 (s,
1H), 4.27 (d, 1H, J = 6.2 Hz), 4.36 (d, 1H, J = 14.1 Hz), 4.89 (d, 1H, J
= 8.9 Hz), 5.06 (d, 1H, J = 9.9 Hz), 5.16 (d, 1H, J = 17.0 Hz), 5.82−
5.83 (m, 1H), 6.83 (d, 2H, J = 6.5 Hz), 6.94 (d, 2H, J = 7.7 Hz), 7.08−
7.15 (m, 5H), 7.19 (dd, 1H, J = 5.0, 0.7 Hz), 7.32 (dd, 1H, J = 4.9, 3.0
Hz), 7.36−7.39 (m, 1H), 7.45 (t, 2H, J = 7.5 Hz), 7.55 (d, 1H, J = 2.0
Hz), 7.87 (d, 2H, J = 7.5 Hz); 13C NMR (CDCl3, 100 MHz) δ 21.5,
34.3, 46.7, 69.5, 75.4, 84.6, 88.4, 117.2, 121.1, 125.8, 126.3, 126.8,
127.9, 128.4, 128.5, 129.2, 129.5, 129.7, 136.0, 136.9, 137.9, 142.9,
143.0; IR (NaCl, neat) v 3414, 3022, 1599, 1449 cm−1; HRMS (ESI)
[M + H]+ calcd for C31H30NO3S2, 528.1667; found, 528.1668.
N-Allyl-N-(3-hydroxy-1,3-diphenylnon-4-yn-2-yl)-4-methyl-
benzenesulfonamide (1j). Yellow solid: yield 94%; 0.472 g; mp =
1
55−57 °C; H NMR (CDCl3, 400 MHz) δ 0.95 (t, 3H, J = 7.3 Hz),
1.44−1.53 (m, 2H), 1.57−1.64 (m, 2H), 2.31 (s, 3H), 2.38 (t, 2H, J =
7.0 Hz), 2.75 (d, 1H, J = 14.3 Hz), 2.87 (d, 1H, J = 11.2 Hz), 3.41 (s,
1H), 4.20−4.29 (m, 2H), 4.77 (d, 1H, J = 9.2 Hz), 5.04 (d, 1H, J =
10.0 Hz), 5.15 (d, 1H, J = 17.1 Hz), 5.75−5.77 (m, 1H), 6.80 (d, 2H, J
= 6.7 Hz), 6.92 (d, 2H, J = 7.8 Hz), 7.06−7.14 (m, 5H), 7.34−7.36
(m, 1H), 7.41 (t, 2H, J = 7.4 Hz), 7.81 (d, 2H, J = 7.5 Hz); 13C NMR
(CDCl3, 100 MHz) δ 13.6, 18.6, 21.4, 22.2, 30.6, 34.4, 46.6, 69.3, 75.0,
80.2, 90.2, 116.8, 126.2, 126.8, 127.9, 128.2, 128.3, 128.4, 129.07,
129.14, 136.1, 137.2, 138.2, 142.8, 143.6; IR (NaCl, neat) v 3410,
N-(3-Hydroxy-1,3,5-triphenylpent-4-yn-2-yl)-N,4-dimethyl-
benzenesulfonamide (1p). Yellow solid: yield 99%; 0.491 g; mp =
129−131 °C; 1H NMR (CDCl3, 400 MHz) δ 2.31 (s, 3H), 2.82−2.97
(m, 2H), 3.04 (s, 3H), 3.52 (s, 1H), 4.83 (dd, 1H, J = 11.0, 3.3 Hz),
6.85 (d, 2H, J = 7.2 Hz), 6.93 (d, 2H, J = 8.2 Hz), 7.00 (d, 2H, J = 8.3
F
dx.doi.org/10.1021/jo401083m | J. Org. Chem. XXXX, XXX, XXX−XXX

The Journal of Organic Chemistry
Article
Hz), 7.07−7.15 (m, 3H), 7.35−7.40 (m, 4H), 7.43−7.47 (m, 2H),
7.52−7.55 (m, 2H), 7.90 (d, 2H, J = 7.2 Hz); 13C NMR (CDCl3, 100
MHz) δ 21.5, 29.7, 33.6, 68.8, 75.3, 89.2, 122.2, 126.4, 126.9, 127.6,
128.5, 128.58, 128.61, 129.0, 129.3, 131.7, 135.7, 138.0, 142.70,
132.74; IR (NaCl, neat) v 3410, 3019, 1599, 1327 cm−1; HRMS (ESI)
[M + H]+ calcd for C31H30NO3S, 496.1946; found, 496.1952.
4.23−4.39 (m, 2H), 4.90 (d, 1H, J = 9.6 Hz), 5.04 (d, 1H, J = 10.0
Hz), 5.15 (d, 1H, J = 17.2 Hz), 5.81−5.83 (m, 1H), 6.60 (d, 2H, J =
8.6 Hz), 6.84 (d, 2H, J = 6 Hz), 7.11−7.14 (m, 5H), 7.35−7.39 (m,
4H), 7.45 (t, 2H, J = 7.5 Hz), 7.52−7.54 (m, 2H), 7.90 (d, 2H, J = 7.5
Hz); 13C NMR (CDCl3, 100 MHz) δ 34.3, 46.7, 55.5, 69.6, 75.4, 89.0,
89.3, 113.7, 117.2, 122.1, 126.4, 126.8, 128.47, 128.54, 128.6, 129.2,
130.0, 131.5, 131.7, 136.0, 138.0, 143.1, 162.5; IR (NaCl, neat) v 3057,
1597, 1490 cm−1; HRMS (ESI) [M + Na]+ calcd for C33H31NO4SNa,
560.1872; found, 560.1871.
N-Butyl-N-(3-hydroxy-1,3,5-triphenylpent-4-yn-2-yl)-4-
methylbenzenesulfonamide (1q). White solid: yield 89%; 0.382 g;
mp = 184−186 °C; 1H NMR (CDCl3, 400 MHz) δ 0.84 (t, 3H, J = 7.2
Hz), 1.18−1.22 (m, 2H), 1.85−1.94 (m, 2H), 2.32 (s, 3H), 2.81 (d,
1H, J = 14.3 Hz), 2.90 (d, 1H, J = 10.2 Hz), 3.42−3.57 (m, 2H), 3.94
(s, 1H), 4.73 (d, 1H, J = 8.2 Hz), 6.69 (d, 2H, J = 7.1 Hz), 7.01 (t, 2H,
J = 7.4 Hz), 7.07−7.16 (m, 3H), 7.34−7.44 (m, 6H), 7.53−7.56 (m,
2H), 7.87 (d, 2H, J = 7.4 Hz); 13C NMR (CDCl3, 100 MHz) δ 13.7,
20.7, 21.5, 32.8, 34.3, 44.5, 75.2, 88.7, 89.0, 122.2, 126.2, 126.9, 127.5,
128.4, 128.46, 128.52, 128.91, 128.94, 129.3, 131.6, 136.6, 137.8,
142.9, 143.3; IR (NaCl, neat) v 3444, 3053, 1599, 1448 cm−1; HRMS
(ESI) [M + H]+ calcd for C34H35NO3S, 538.2418; found, 538.2418.
N-Benzyl-N-(3-hydroxy-1,3,5-triphenylpent-4-yn-2-yl)-4-
methylbenzenesulfonamide (1r). Yellow solid; yield: 80%; 0.457
1-Allyl-2-benzyl-3,5-diphenyl-4-tosyl-1H-pyrrole (2b).16 Col-
orless solid: 0.068 g; mp = 118−119 °C; 1H NMR (CDCl3, 400 MHz)
δ 2.32 (s, 3H), 3.78 (s, 2H), 4.00−4.01 (m, 2H), 4.66 (dd, 1H, J =
17.1, 0.9 Hz), 5.04 (dd, 1H, J = 10.4, 0.92 Hz), 5.51−5.59 (m, 1H),
6.98−7.00 (m, 4H), 7.14−7.18 (m, 3H), 7.22−7.30 (m, 7H), 7.33−
7.43 (m, 5H); 13C NMR (CDCl3, 100 MHz) δ 21.5, 30.3, 47.0, 116.6,
120.4, 123.7, 126.4, 127.1, 127.6, 127.75, 127.80, 128.68, 128.72,
129.0, 129.6, 130.6, 131.3, 131.5, 133.4, 133.6, 136.7, 138.8, 141.0,
142.3; IR (NaCl, neat) v 3019, 1599, 1493, 1454 cm−1; HRMS (ESI)
[M + Na]+ calcd for C33H29NO2S, 526.1817; found, 526.1835.
1-Allyl-2-benzyl-5-phenyl-3-(p-tolyl)-4-tosyl-1H-pyrrole (2c).
1
1
g; mp = 165−167 °C; H NMR (CDCl3, 400 MHz) δ 2.28 (s, 3H),
Brown solid: 0.055 g; mp = 128−130 °C; H NMR (CDCl3, 400
2.84 (d, 1H, J = 13.8 Hz), 2.94 (d, 1H, J = 9.32 Hz), 3.59−3.73 (m,
1H), 4.92−5.00 (m, 2H), 6.64−6.66 (m, 2H), 6.83−6.86 (m, 2H),
7.04−7.19 (m, 8H), 7.30−7.45 (m, 10H), 7.89−7.91 (m, 2H); 13C
NMR (CDCl3, 100 MHz) δ 21.4, 34.9, 48.2, 69.5, 75.3, 88.8, 89.9,
122.1, 126.2, 126.8, 127.3, 127.6, 128.1, 128.2, 128.5, 128.6, 128.9,
129.1, 129.4, 131.7, 137.3, 137.7, 142.6, 143.5; IR (NaCl, neat) v 3419,
3019, 1599, 1447 cm−1; HRMS (ESI) [M + Na]+ calcd for
C37H33NO3SNa, 594.2079; found, 594.2099.
MHz) δ 2.32 (s, 3H), 2.36 (s, 3H), 3.78 (s, 2H), 3.98−3.99 (m, 2H),
4.65 (dd, 1H, J = 17.1, 0.8 Hz), 5.02 (dd, 1H, J = 10.4, 0.9 Hz), 5.51−
5.57 (m, 1H), 6.97−7.01 (m, 4H), 7.10 (d, 2H, J = 7.9 Hz), 7.15−7.18
(m, 4H), 7.21−7.25 (m, 3H), 7.31−7.42 (m, 5H); 13C NMR (CDCl3,
100 MHz) δ 21.4, 21.5, 30.3, 47.0, 116.5, 120.4, 123.7, 126.4, 127.2,
127.8, 127.8, 128.3, 128.7, 128.7, 129.0, 129.6, 130.6, 131.3, 133.4,
136.7, 136.8, 138.9, 141.2, 142.3; IR (NaCl, neat) v 3019, 2399, 1599,
1495 cm−1; HRMS (ESI) [M + H]+ calcd for C34H32NO2S, 518.2154;
found, 518.2171.
N-Cinnamyl-N-(3-hydroxy-1,3,5-triphenylpent-4-yn-2-yl)-4-
methylbenzenesulfonamide (1s). Yellow solid: yield 49%; 0.293 g;
mp = 79−81 °C; 1H NMR (CDCl3, 400 MHz) δ 2.23 (s, 3H), 2.92 (d,
1H, J = 14.1 Hz), 3.04 (d, 1H, J = 11.2 Hz), 3.56 (s, 1H), 4.46 (dd,
1H, J = 16.1, 5.4 Hz), 4.56 (dd, 1H, J = 16.3, 6.9 Hz), 5.03 (d, 1H, J =
9.3 Hz), 5.82−5.89 (m, 1H), 6.37 (d, 1H, J = 15,9 Hz), 6.85−6.92 (m,
3H), 7.03−7.09 (m, 4H), 7.13−7.25 (m, 7H), 7.34−7.40 (m, 4H),
7.46 (t, 2H, J = 7.4 Hz), 7.53 (d, 2H, J = 6.2 Hz), 7.92 (d, 2H, J = 7.4
Hz); 13C NMR (CDCl3, 100 MHz) δ 21.4, 34.6, 46.2, 69.3, 75.5, 89.2,
89.5, 122.1, 126.3, 126.4, 126.7, 126.8, 127.7, 128.0, 128.5, 128.57,
128.61, 129.05, 129.12, 129.4, 131.7, 132.2, 136.4, 137.5, 138.0, 142.9,
143.1; IR (NaCl, neat) v 3400, 3019, 1599, 1449 cm−1; HRMS (ESI)
[M + H]+ calcd for C39H36NO3S, 598.2416; found, 598.2406.
N-Allyl-N-(3-hydroxy-1,3,5-triphenylpent-4-yn-2-yl)-
methanesulfonamide (1t). Brown solid: yield 75%; 0.334 g; mp =
1-Allyl-2-benzyl-3-(4-chlorophenyl)-5-phenyl-4-tosyl-1H-
1
pyrrole (2d). Gray solid: 0.042 g; mp = 155−157 °C; H NMR
(CDCl3, 400 MHz) δ 2.33 (s, 3H), 3.77 (s, 2H), 4.00−4.01 (m, 2H),
4.65 (dd, 1H, J = 17.1, 0.8 Hz), 5.04 (dd, 1H, J = 10.4, 0.8 Hz), 5.51−
5.60 (m, 1H), 6.95 (d, 2H, J = 7.1 Hz), 7.02 (d, 2H, J = 8.1 Hz), 7.15−
7.28 (m, 9H), 7.31−7.33 (m, 2H), 7.37−7.43 (m, 3H); 13C NMR
(CDCl3, 100 MHz) δ 21.5, 30.2, 47.0, 116.7, 120.4, 122.3, 126.6,
127.1, 127.7, 127.79, 127.81, 128.7, 128.8, 129.1, 129.7, 130.3, 131.3,
132.2, 132.8, 133.3, 137.1, 138.5, 140.9, 142.6; IR (NaCl, neat) v 3019,
2399, 1597, 1489 cm−1; HRMS (ESI) [M + H]+ calcd for
C33H29ClNO2S, 538.1639; found, 538.1619.
1-Allyl-2-benzyl-5-phenyl-3-(thiophen-2-yl)-4-tosyl-1H-pyr-
role (2e). Brown solid: 0.049 g; mp = 133−135 °C; 1H NMR
(CDCl3, 400 MHz) δ 2.34 (s, 3H), 3.88 (s, 2H), 3.99−4.00 (m, 2H),
4.67 (dd, 1H, J = 17.0, 0.5 Hz), 5.03 (dd, 1H, J = 15.0, 0.6 Hz), 5.48−
5.58 (m, 1H), 7.00−7.06 (m, 6H), 7.15−7.19 (m, 1H), 7.15−7.29 (m,
5H), 7.32−7.34 (m, 2H), 7.34−7.44 (m, 3H); 13C NMR (CDCl3,100
MHz) δ 21.5, 30.5, 47.1, 11.5.1, 116.8, 126.2, 126.5, 126.7, 127.2,
127.8, 127.9, 128.7, 128.9, 129.1, 130.1, 130.3, 131.2, 131.9, 133.1,
133.3, 137.3, 138.4, 140.7, 142.5, 143.1; IR (NaCl, neat) v 3019, 2399,
1597, 1472 cm−1; HRMS (ESI) [M + H]+ calcd for C31H28NO2S2,
510.1561; found, 510.1571.
1
100−102 °C; H NMR (CDCl3, 400 MHz) δ 2.23 (s, 3H), 2.94 (d,
1H, J = 14.2 Hz), 3.04 (d, 1H, J = 11.4 Hz), 3.27 (s, 1H), 4.21−4.30
(m, 2H), 4.73 (d, 1H, J = 9.9 Hz), 5.21 (d, 1H, J = 9.6 Hz), 5.33 (d,
1H, J = 17.2), 6.12−6.15 (m, 1H), 7.06 (d, 2H, J = 7.2 Hz), 7.15−7.18
(m, 1H), 7.22−7.25 (m, 2H), 7.35−7.39 (m, 4H), 7.45 (t, 2H, J = 7.5
Hz), 7.53−7.56 (m, 2H), 7.85 (d, 2H, J = 7.4 Hz); 13C NMR (CDCl3,
100 MHz) δ 34.4, 41.0, 46.9, 69.3, 75.6, 89.1, 118.7, 122.0, 126.7,
126.9, 128.55, 128.59, 128.6, 129.1, 129.3, 131.7, 135.5, 138.0, 143.3;
IR (NaCl, neat) v 3458, 3019, 1599, 1449 cm−1; HRMS (ESI) [M +
Na]+ calcd for C27H27NO3S, 468.1609; found, 468.1618.
1-Allyl-2-benzyl-3-ethyl-5-phenyl-4-tosyl-1H-pyrrole (2f).
1
Brown solid: 0.037 g; mp = 135−137 °C; H NMR (CDCl3, 400
MHz) δ 1.15 (t, 3H, J = 7.4 Hz), 2.35 (s, 3H), 2.83 (q, 2H, J = 7.6
Hz), 3.92−3.95 (m, 4H), 4.59 (dd, 1H, J = 17.1, 0.8 Hz), 5.00 (dd,
1H, J = 10.4, 0.8 Hz), 5.48−5.55 (m, 1H), 7.05 (d, 2H, J = 7.2 Hz),
7.11 (d, 2H, J = 8.1 Hz), 7.14−7.18 (m, 2H), 7.20 (d, 1H, J = 7.3 Hz),
7.28−7.32 (m, 4H), 7.36 (d, 1H, J = 7.4 Hz), 7.44 (d, 2H, J = 8.2 Hz);
13C NMR (CDCl3, 100 MHz) δ 16.8, 18.1, 21.5, 29.8, 46.8, 116.3,
N-Allyl-4-chloro-N-(3-hydroxy-1,3,5-triphenylpent-4-yn-2-
yl)benzenesulfonamide (1u). Pale-yellow solid: yield 76%; 0.412 g;
1
mp = 137−139 °C; H NMR (CDCl3, 400 MHz) δ 2.89 (d, 1H, J =
14.2 Hz), 2.97 (d, 1H, J = 11.0 Hz), 3.55 (s, 1H), 4.27−4.38 (m, 2H),
4.90 (d, 1H, J = 9.5 Hz), 5.03 (d, 1H, J = 10.1 Hz), 5.16 (d, 1H, J =
17.1 Hz), 5.73−5.77 (m, 1H), 6.85 (d, 2H, J = 7.1 Hz), 7.04 (s, 4H),
7.10−7.20 (m, 3H), 7.33−7.39 (m, 4H), 7.45 (t, 2H, J = 7.5 Hz),
7.50−7.53 (m, 2H), 7.90 (d, 2H, J = 7.5 Hz); 13C NMR (CDCl3, 100
MHz) δ 34.4, 46.9, 69.9, 75.4, 89.0, 89.4, 117.7, 122.0, 125.4, 126.6,
126.8, 128.7, 129.1, 129.25, 129.32, 131.7, 135.6, 138.1, 138.4, 138.9,
143.2, 150.9; IR (NaCl, neat) v 3019, 1585, 1329 cm−1; HRMS (ESI)
[M + Na]+ calcd for C32H28ClNO3SNa, 564.1376; found, 564.1369.
N-Allyl-N-(3-hydroxy-1,3,5-triphenylpent-4-yn-2-yl)-4-me-
thoxybenzenesulfonamide (1v). Pale-yellow solid: yield 92%;
123.8, 126.5, 126.7, 127.6, 127.8, 128.4, 128.7, 128.8, 129.0, 129.4,
130.5, 131.4, 133.6, 136.7, 138.8, 142.3; IR (NaCl, neat) v 3019, 2438,
1599, 1495 cm−1; HRMS (ESI) [M + H]+ calcd for C29H30NO2S,
456.1997; found, 456.2005.
1-Allyl-2-benzyl-3-phenyl-5-(p-tolyl)-4-tosyl-1H-pyrrole
(2g). Dark-brown solid: 0.060 g; mp = 67−70 °C; 1H NMR (CDCl3,
400 MHz) δ 2.32 (s, 3H), 2.40 (s, 3H), 3.77 (s, 2H), 4.00−4.01 (m,
2H), 4.67 (dd, 1H, J = 17.1, 0.8 Hz), 5.04 (dd, 1H, J = 10.4, 0.8 Hz),
5.53−5.60 (m, 1H), 6.97−7.00 (m, 4H), 7.15−7.19 (m, 3H), 7.21−
7.29 (m, 11H); 13C NMR (CDCl3, 100 MHz) δ 21.49, 21.51, 30.3,
1
0.369 g; mp = 122−124 °C; H NMR (CDCl3, 400 MHz) δ 2.85 (d,
1H, J = 14.4 Hz), 2.96−3.02 (m, 1H), 3.68 (s, 1H), 3.77 (s, 3H),
G
dx.doi.org/10.1021/jo401083m | J. Org. Chem. XXXX, XXX, XXX−XXX

The Journal of Organic Chemistry
Article
46.9, 116.5, 120.3, 123.6, 126.4, 127.12, 127.14, 127.5, 127.6, 127.8,
128.5, 128.67, 128.70, 129.5, 131.1, 131.6, 133.5, 133.6, 137.0, 138.83,
138.84, 141.1, 142.3; IR (NaCl, neat) v 3019, 2399, 1599, 1493, 1389
cm−1; HRMS (ESI) [M + H]+ calcd for C34H32NO2S, 518.2154;
found, 518.2153.
1-Allyl-2,3,5-triphenyl-4-tosyl-1H-pyrrole (2n). Yellow solid:
0.069 g; mp = 136−138 °C; H NMR (CDCl3, 400 MHz) δ 2.29 (s,
1
3H), 4.21−4.22 (m, 2H), 4.54 (dd, 1H, J = 17.1, 0.9 Hz), 4.93 (dd,
1H, J = 10.3, 0.9 Hz), 5.41−5.49 (m, 1H), 6.96 (d, 2H, J = 8.1 Hz),
7.12−7.17 (m, 9H), 7.18−7.20 (m, 3H), 7.43−7.46 (m, 5H); 13C
NMR (CDCl3, 100 MHz) δ 21.5, 27.5, 117.0, 121.2, 123.2, 126.7,
127.1, 127.2, 127.8, 127.97, 128.04, 128.7, 129.0, 130.8, 130.9, 131.2,
131.5, 131.9, 133.1, 133.3, 133.4, 136.9, 140.8, 142.4; IR (NaCl, neat)
v 3019, 2399, 1599, 1464 cm−1; HRMS (ESI) [M + H]+ calcd for
C32H28NO2S, 490.1841; found, 490.1847.
1-Allyl-2-benzyl-5-(4-bromophenyl)-3-phenyl-4-tosyl-1H-
1
pyrrole (2h). Brown solid: 0.065 g; mp = 129−131 °C; H NMR
(CDCl3, 400 MHz) δ 2.32 (s, 3H), 3.77 (s, 2H), 4.00−4.01 (m, 2H),
4.65 (dd, 1H, J = 17.1, 0.6 Hz), 5.05 (dd, 1H, J = 10.4, 0.7 Hz), 5.50−
5.60 (m, 1H), 6.96−7.01 (m, 4H), 7.13−7.18 (m, 3H), 7.22−7.25 (m,
6H), 7.27−7.29 (m, 3H), 7.52 (d, 2H, J = 1.6 Hz); 13C NMR (CDCl3,
100 MHz) δ 21.5, 30.3, 47.0, 116.7, 120.8, 123.6, 123.8, 126.5, 127.1,
127.3, 127.6, 127.8, 128.7, 128.8, 129.6, 130.1, 131.1, 131.5, 132.9,
133.2, 133.3, 135.3, 138.6, 140.7, 142.6; IR (NaCl, neat) v 3019, 2399,
1597, 1493 cm−1; HRMS (ESI) [M + H]+ calcd for C33H29BrNO2S,
582.1102; found, 582.1113.
1-Allyl-2-isopropyl-3,5-diphenyl-4-tosyl-1H-pyrrole (2o). Yel-
low solid: 0.033 g; mp = 114−116 °C; 1H NMR (CDCl3, 400 MHz) δ
0.98 (s, 3H), 0.99 (s, 3H), 2.32 (s, 3H), 2.88 (sep, 1H, J = 7.1 Hz),
4.25−4.27 (m, 2H), 4.75 (dd, 1H, J = 17.1, 0.8 Hz), 5.13 (dd, 1H, J =
10.5, 0.9 Hz), 6.99 (d, 2H, J = 8.0 Hz), 7.07 (d, 2H, J = 8.3 Hz), 7.13−
7.16 (m, 2H), 7.24−7.31 (m, 3H), 7.36−7.45 (m, 5H); 13C NMR
(CDCl3, 100 MHz) δ 21.5, 22.6, 26.4, 46.6, 116.5, 120.8, 124.3, 127.0,
127.3, 127.7, 128.7, 128.9, 131.2, 131.3, 132.3, 134.0, 134.3, 135.4,
136.1, 141.0, 142.2; IR (NaCl, neat) v 3017, 2399, 1605, 1472 cm−1;
HRMS (ESI) [M + H]+ calcd for C29H30NO2S, 456.1997; found,
456.1996.
2-Benzyl-1-methyl-3,5-diphenyl-4-tosyl-1H-pyrrole (2p).
Dark-green solid: 0.074 g; mp = 183−185 °C 1H NMR (CDCl3,
400 MHz) δ 2.30 (s, 3H), 3.05 (s, 3H), 3.81 (s, 2H), 6.97−7.00 (m,
4H), 7.13−7.18 (m, 3H), 7.22−7.30 (m, 7H), 7.34−7.36 (m, 2H),
7.41−7.44 (m, 3H); 13C NMR (CDCl3, 100 MHz) δ 21.5, 30.6, 32.1,
120.0, 123.1, 126.4, 127.1, 127.2, 127.6, 127.9, 128.0, 128.72, 128.74,
129.0, 129.8, 130.8, 131.3, 131.5, 133.7, 136.7, 138.5, 141.1, 142.3; IR
(NaCl, neat) v 3019, 1597, 1493, 1454 cm−1; HRMS (ESI) [M + H]+
calcd for C31H28NO2S, 478.1841; found, 478.1855.
1-Allyl-2-benzyl-3-phenyl-5-(thiophen-3-yl)-4-tosyl-1H-pyr-
1
role (2i). Brown solid: 0.062 g; mp = 83−85 °C; H NMR (CDCl3,
400 MHz) δ 2.32 (s, 3H), 3.77 (s, 2H), 4.04−4.05 (m, 2H), 4.68 (dd,
1H, J = 17.1, 0.9 Hz), 5.05 (dd, 1H, J = 10.4, 0.9 Hz), 5.55−5.63 (m,
1H), 6.97−7.02 (m, 4H), 7.07 (dd, 1H, J = 4.6, 1.5 Hz), 7.16−7.23
(m, 5H), 7.26−7.34 (m, 7H); 13C NMR (CDCl3, 100 MHz) δ 21.5,
30.3, 47.1, 116.5, 121.1, 124.0, 124.6, 126.5, 127.0, 127.2, 127.6, 127.9,
128.7, 128.8, 129.7, 130.0, 130.2, 131.5, 133.5, 133.6, 138.6, 140.9,
132.4; IR (NaCl, neat) v 3019, 2399, 1599, 1495 cm−1; HRMS (ESI)
[M + H]+ calcd for C31H28NO2S2, 510.1561; found, 510.1566.
1-Allyl-2-benzyl-5-butyl-3-phenyl-4-tosyl-1H-pyrrole (2j).
1
Dark-yellow oil: 0.074 g; H NMR (CDCl3, 400 MHz) δ 0.95 (t,
3H, J = 7.3 Hz), 1.41−1.50 (m, 2H), 1.59−1.66 (m, 2H), 2.33 (s, 3H),
2.99−3.03 (m, 2H), 3.67 (s, 2H), 4.23−4.24 (m, 2H), 4.74 (d, 1H, J =
17.1 Hz), 5.10 (d, 1H, J = 11.0 Hz), 5.65−5.70 (m, 1H), 6.93 (d, 2H, J
= 7.1 Hz), 7.02−7.07 (m, 4H), 7.15−7.25 (m, 6H), 7.29 (d, 2H, J =
8.2 Hz); 13C NMR (CDCl3, 100 MHz) δ 13.9, 21.5, 23.0, 24.8, 30.2,
33.1, 46.2, 116.4, 117.5, 123.3, 126.4, 126.9, 127.4, 127.7, 128.6, 128.8,
128.9, 131.6, 133.2, 133.6, 138.3, 138.9, 141.3, 142.2; IR (NaCl, neat)
v 3019, 2399, 1601, 1408 cm−1; HRMS (ESI) [M + H]+ calcd for
C31H34NO2S, 484.2310; found, 484.2318.
2-Benzyl-1-butyl-3,5-diphenyl-4-tosyl-1H-pyrrole (2q).
1
Brown solid: 0.083 g; mp = 167−169 °C; H NMR (CDCl3, 400
MHz) δ 0.55 (t, 3H, J = 7.2 Hz), 0.87 (sextet, 2H, J = 7.2 Hz), 1.09−
1.17 (m, 2H), 2.31 (s, 3H), 3.39−3.43 (m, 2H), 3.81 (s, 2H), 6.97−
7.02 (m, 4H), 7.12−7.18 (m, 3H), 7.21−7.30 (m, 7H), 7.34−7.37 (m,
2H), 7.40−7.43 (m, 3H); 13C NMR (CDCl3, 100 MHz) δ 13.3, 19.8,
21.5, 30.6, 32.6, 44.7, 120.2, 123.3, 126.4, 127.08, 127.14, 127.5, 127.8,
127.9, 128.6, 128.7, 128.8, 129.3, 131.0, 131.4, 131.6, 133.8, 136.4,
138.9, 141.1, 142.2; IR (NaCl, neat) v 3055, 2303, 1599 cm−1; HRMS
(ESI) [M + H]+ calcd for C34H34NO2S, 520.2310; found, 520.2301.
1,2-Dibenzyl-3,5-diphenyl-4-tosyl-1H-pyrrole (2r). Colorless
1-Allyl-2-benzyl-5-cyclopropyl-3-phenyl-4-tosyl-1H-pyrrole
(2k). Dark-green solid: 0.067 g; mp = 107−109 °C; 1H NMR (CDCl3,
400 MHz) δ 0.89−0.91 (m, 2H), 1.05−1.10 (m, 2H), 1.69−1.76 (m,
1H), 2.32 (s, 3H), 3.68 (s, 2H), 4.46−4.48 (m, 2H), 4.72 (dd, 1H, J =
17.1, 0.8 Hz), 5.11 (dd, 1H, J = 10.4, 0.8 Hz), 5.71−5.79 (m, 1H), 6.93
(d, 2H, J = 7.1 Hz), 7.02 (d, 2H, 8.0 Hz), 7.07−7.10 (m, 2H), 7.14−
7.25 (m, 6H), 7.36 (d, 2H, J = 8.3 Hz); 13C NMR (CDCl3, 100 MHz)
δ 6.7, 8.2, 21.5, 30.1, 46.7, 116.1, 120.3, 123.5, 126.4, 126.9, 127.0,
127.4, 127.7, 128.6, 128.7, 128.8, 131.4, 133.5, 133.8, 137.4, 138.9,
141.2, 142.3; IR (NaCl, neat) v 3019, 2399, 1601, 1454 cm−1; HRMS
(ESI) [M + H]+ calcd for C30H30NO2S, 468.1997; found, 468.2007.
1-Allyl-2-benzyl-5-(cyclohex-1-en-1-yl)-3-phenyl-4-tosyl-1H-
1
solid: 0.063 g; mp = 194−196 °C; H NMR (CDCl3, 400 MHz) δ
2.33 (s, 3H), 3.59 (s, 2H), 4.62 (s, 2H), 6.71 (d, 2H, J = 6.6 Hz), 6.92
(d, 2H, J = 7.2 Hz), 7.01 (d, 2H, J = 8.0 Hz), 7.15−7.36 (m, 18H), 13C
NMR (CDCl3, 100 MHz) δ 21.5, 30.5, 48.1, 120.6, 124.1, 125.6, 126.5,
127.18, 127.21, 127.4, 127.6, 127.79, 127.81, 128.7, 128.8, 129.0,
129.9, 130.4, 131.3, 131.5, 133.5, 137.1, 137.4, 138.7, 141.0, 142.4; IR
(NaCl, neat) v 3019, 2399, 1524, 1393 cm−1; HRMS (ESI) [M + H]+
calcd for C37H32NO2S, 554.2154; found, 554.2145.
1
pyrrole (2l). Yellow oil: 0.093 g; H NMR (CDCl3, 400 MHz) δ
2-Benzyl-1-cinnamyl-3,5-diphenyl-4-tosyl-1H-pyrrole (2s).
Reddish-brown solid: 0.044 g; mp = 153−155 °C; 1H NMR
(CDCl3, 400 MHz) δ 2.32 (s, 3H), 3.84 (s, 2H), 4.18 (d, 2H),
5.69−5.74 (m, 1H), 5.82 (d, 1H, J = 15.9 Hz), 7.01 (t, 4H, J = 8.8 Hz),
7.12−7.19 (m, 5H), 7.23−7.35 (m, 10H), 7.35−7.44 (m, 5H); 13C
NMR (CDCl3, 100 MHz) δ 21.5, 30.5, 46.8, 124.4, 126.4, 126.5, 127.2,
127.6, 127.8, 128.0, 128.6, 128.8, 129.0, 129.6, 130.7, 131.5, 131.6,
132.1, 133.6, 136.0, 136.9, 138.7, 141.0, 142.3; IR (NaCl, neat) v 3019,
2399, 1599, 1391 cm−1; HRMS (ESI) [M + H]+ calcd for
C39H34NO2S, 580.2310; found, 580.2328.
1.60−1.81 (m,4H), 2.02−2.27 (m, 3H), 2.33 (s, 3H), 2.57−2.61 (m,
1H), 3.71 (d, 2H, J = 8.6 Hz), 4.09 (d, 1H, J = 16.2 Hz), 4.25 (d, 1H, J
= 12.7 Hz), 4.79 (dd, 1H, J = 17.1, 0.8 Hz), 5.08 (dd, 1H, J = 10.3, 0.8
Hz), 5.64−5.71 (m, 2H), 6.93 (d, 2H, J = 7.2 Hz), 7.05 (d, 2H, J = 8.0
Hz), 7.15−7.16 (m, 3H), 7.20−7.25 (m, 5H), 7.33 (d, 2H, 8.4 Hz);
13C NMR (CDCl3, 100 MHz) δ 21.5, 21.7, 22.7, 25.6, 30.3, 30.9, 46.8,
116.5, 118.2, 123.2, 126.4, 127.0, 127.1, 127.5, 127.8, 128.6, 128.7,
129.7, 131.5, 132.2, 133.6, 134.1, 139.0, 139.5, 141.4, 142.2; IR (NaCl,
neat) v 3019, 2399, 1599, 1495 cm−1; HRMS (ESI) [M + H]+ calcd
for C33H34NO2S, 508.2310; found, 508.2312.
1-Allyl-2-benzyl-3-phenyl-4-tosyl-1H-pyrrole (2m). Brown oil:
0.037 g; H NMR (CDCl3, 400 MHz) δ 2.34 (s, 3H), 3.79 (s, 2H),
1-Allyl-2-benzyl-4-((4-methoxyphenyl)sulfonyl)-3,5-diphen-
yl-1H-pyrrole (2t). Yellow solid: 0.066 g; mp = 57−59 °C; 1H NMR
(CDCl3, 400 MHz) δ 3.78 (s, 3H), 3.99−4.01 (m, 2H), 4.66 (dd, 1H,
J = 17.1, 0.7 Hz), 5.03 (dd, 1H, J = 10.4, 0.8 Hz), 5.51−5.60 (m, 1H),
6.65−6.67 (m, 2H), 6.98 (d, 2H), 7.16−7.22 (m, 3H), 7.24−7.27 (m,
7H), 7.27−7.34 (m, 5H); 13C NMR (CDCl3, 100 MHz) δ 30.3, 46.9,
55.5, 113.2, 116.5, 120.8, 123.5, 126.4, 127.1, 127.6, 127.75, 127.78,
128.7, 128.9, 129.2, 129.5, 130.6, 131.3, 131.5, 133.4, 133.6, 135.8,
136.6, 138.8, 162.2; IR (NaCl, neat) v 3053, 2304, 1495 cm−1; HRMS
(ESI) [M + H]+ calcd for C33H30NO3S, 520.1946; found, 520.1948.
1
4.22 (d, 2H, J = 5.2 Hz), 5.02 (d, 1H, J = 17.0 Hz), 5.20 (d, 1H, J = 0.2
Hz), 5.71−5.81 (m, 1H), 6.95 (d, 2H, J = 7.3 Hz), 7.05 (d, 2H, J = 7.9
Hz), 7.13−7.26 (m, 8H), 7.35 (d, 2H, J = 8.0 Hz), 7.43 (s, 1H); 13C
NMR (CDCl3, 100 MHz) δ 21.5, 30.1, 50.2, 118.7, 122.9, 123.0, 125.4,
126.5, 127.2, 127.3, 127.3, 127.7, 127.8, 128.7, 129.0, 130.8, 131.1,
132.5, 132.8, 138.5, 140.0, 142.7; IR (NaCl, neat) v 3019, 2399, 1746,
1599 cm−1; HRMS (ESI) [M + H]+ calcd for C27H26NO2S, 428.1684;
found, 428.1689.
H
dx.doi.org/10.1021/jo401083m | J. Org. Chem. XXXX, XXX, XXX−XXX

The Journal of Organic Chemistry
Article
1-Allyl-2-benzyl-4-((4-chlorophenyl)sulfonyl)-3,5-diphenyl-
1H-pyrrole (2u). Yellow solid: 0.054 g; mp = 132−134 °C; 1H NMR
(CDCl3, 400 MHz) δ 3.79 (s, 2H), 4.01−4.03 (m, 2H), 4.66 (dd, 1H,
J = 17.1, 0.8 Hz), 5.05 (dd, 1H, J = 10.4, 0.8 Hz), 5.52−5.60 (m, 1H),
6.98 (d, 2H, J = 7.2 Hz), 7.16−7.19 (m, 4H), 7.22−7.25 (m, 5H),
7.29−7.35 (m, 5H), 7.39−7.45 (m, 3H); 13C NMR (CDCl3, 100
MHz) δ 30.3, 47.0, 116.7, 126.5, 127.4, 127.7, 127.8, 127.9, 128.3,
128.6, 128.7, 129.2, 129.9, 130.3, 131.2, 131.5, 133.2, 137.2, 138.2,
138.6, 142.2; IR (NaCl, neat) v 3019, 2399, 1584, 1476 cm−1; HRMS
(ESI) [M + Na]+ calcd for C32H26ClNO2SNa, 546.1270; found,
546.1280.
1-Allyl-2-benzyl-4-(methylsulfonyl)-3,5-diphenyl-1H-pyrrole
(2v). Reddish-brown solid: 0.035 g; mp = 80−82 °C; 1H NMR
(CDCl3, 400 MHz) δ 2.64 (s, 3H), 3.89 (s, 2H), 4.07−4.08 (m, 2H),
4.73 (d, 1H, J = 17.1 Hz), 5.10 (d, 1H, J = 10.4 Hz), 5.57−5.67 (m,
1H), 7.05 (d, 2H, J = 7.2 Hz); 7.20−7.38 (m, 6H); 7.40−7.41 (m,
5H), 7.49 (d, 2H, J = 7.6 Hz); 13C NMR (CDCl3, 100 MHz) δ 30.4,
45.2, 47.0, 116.6, 119.9, 123.0, 126.6, 127.6, 127.8, 128.0, 128.1, 128.8,
129.2, 129.7, 130.4, 131.1, 131.3, 133.4, 133.5, 136.6, 138.7; IR (NaCl,
neat) v 3019, 2399, 1605, 1493 cm−1; HRMS (ESI) [M + H]+ calcd
for C27H26NO2S, 428.1684; found, 428.1699.
1-Allyl-2-benzyl-3,5-diphenyl-1H-pyrrole (5b). Dark-yellow
oil: 1H NMR (CDCl3, 400 MHz) δ 4.17 (s, 2H), 4.31−4.33 (m,
2H), 4.83 (dd, 1H, J = 17.1, 1.2 Hz), 5.13 (dd, 1H, J = 10.4, 1.2 Hz),
5.80−5.87 (m, 1H), 6.47 (s, 1H), 7.15−7.21 (m, 5H), 7.29−7.34 (m,
5H), 7.36−7.47 (m, 5H); 13C NMR (CDCl3, 100 MHz) δ 30.8, 46.7,
108.8, 115.9, 124.0, 125.5, 126.2, 127.0, 127.75, 127.82, 129.9, 128.4,
128.5, 128.7, 128.8, 133.5, 134.5, 135.0, 137.0, 140.1; IR (NaCl, neat)
v 3017, 1603,1493 cm−1; HRMS (ESI) [M + H]+ calcd for C26H24N,
530.1909; found, 350.1920.
38, 2269. (g) Hashmi, A. S. K.; Rudolph, M. Chem. Soc. Rev. 2008, 37,
1766. (h) Jimenez-Nunez, E.; Echavarren, M. Chem. Rev. 2008, 108,
́
́
̃
3326. (i) Gorin, D. J.; Sherry, B. D.; Toste, F. D. Chem. Rev. 2008, 108,
3351. (j) Patil, N. T.; Yamamoto, Y. Chem. Rev. 2008, 108, 3395.
(k) Gorin, D. J.; Toste, F. D. Nature 2007, 446, 395. (l) Hashmi, A. S.
K. Chem. Rev. 2007, 107, 3180. (m) Hashmi, A. S. K. Angew. Chem.,
Int. Ed. 2006, 45, 7896. (n) Zhang, L.; Sun, J.; Kozmin, S. A. Adv.
Synth. Catal. 2006, 348, 2271.
(2) For selected examples of studies probing the mechanisms in gold-
catalyzed organic reactions, see: (a) Hansmann, M. M.; Rominger, F.;
Hashmi, A. S. K. Chem. Sci. 2013, 4, 1552. (b) Klatt, G.; Xu, R.;
Pernpointner, M.; Molinari, L.; Hung, T. Q.; Rominger, F.; Hashmi, A.
S. K.; Koppel, H. Chem.−Eur. J. 2013, 19, 3954. (c) Hansmann, M. M.;
̈
Rudolph, M.; Rominger, F.; Hashmi, A. S. K. Angew. Chem., Int. Ed.
́ ́
2013, 52, 2593. (d) Gomez-Suarez, A.; Dupuy, S.; Slawin, A. M. Z.;
Nolan, S. P. Angew. Chem., Int. Ed. 2013, 52, 938. (e) Wang, W.;
Hammond, G. B.; Xu, B. J. J. Am. Chem. Soc. 2012, 134, 5697.
(f) Dupuy, S.; Crawford, L.; Buhl, M.; Slawin, A. M. Z.; Nolan, S. P.
̈
Adv. Synth. Catal. 2012, 354, 2380. (g) Lop
́
ez-Carrillo, V.; Huguet, N.;
Mosquera, A.; Echavarren, A. M. Chem.−Eur. J. 2011, 17, 10972.
(h) Perez-Galan, P.; Herrero-Gomez, E.; Hog, D. T.; Martin, N. J. A.;
́
́
́
́
Maseras, F.; Echavarren, A. M. Chem. Sci. 2011, 2, 141. (i) Egorova, O.
A.; Seo, H.; Kim, Y.; Moon, D.; Rhee, Y. M.; Ahn, K. H. Angew. Chem.,
Int. Ed. 2011, 50, 11446. (j) Hashmi, A. S. K. Angew. Chem., Int. Ed.
2010, 49, 5232. (k) Wang, Z. J.; Benitez, D.; Tkatchouk, E.; Goddard,
W. A., III; Toste, F. D. J. J. Am. Chem. Soc. 2010, 132, 13064.
́
(l) Echavarren, A. M. Nature Chem. 2009, 1, 431. (m) Mauleon, P.;
Krinsky, J. L.; Toste, F. D. J. J. Am. Chem. Soc. 2009, 131, 4513.
(n) Liu, L.-P.; Xu, B.; Mashuta, M. S.; Hammond, G. B. J. J. Am. Chem.
Soc. 2008, 130, 17642.
2-Benzyl-2,4-diphenylbut-3-ynal (6b). Yellow oil: 1H NMR
(CDCl3, 400 MHz) δ 3.26 (d, 1H, J = 13.2 Hz), 3.54 (d, 1H, J = 13.2
Hz), 6.99−7.01 (m, 2H), 7.13−7.15 (m, 3H), 7.29−7.44 (m, 10H);
13C NMR (CDCl3, 100 MHz) δ 42.3, 59.5, 85.4, 91.5, 122.5, 126.6,
127.6, 128.2, 128.4, 128.65, 128.67, 128.71, 128.8, 130.7, 131.7, 135.4,
136.2; IR (NaCl, neat) v 3028, 1728 cm−1; HRMS (DART) [M + H]+
calcd for C23H19O, 311.1436; found, 311.1431.
(3) For a review on carbodeauration processes, see: Adcock, H. V.;
Davies, P. W. Synthesis 2012, 3401.
(4) (a) Park, S. R.; Kim, C.; Kim, D.-G.; Thrimurtulu, N.; Yeom, H.-
S.; Jun, J.; Shin, S.; Rhee, Y. H. Org. Lett. 2013, 15, 1166. (b) Hashmi,
A. S. K.; Lothschutz, C.; Dopp, R.; Ackermann, M.; Becker, J. D. B.;
̈
̈
Rudolph, M.; Scholz, C.; Rominger, F. Adv. Synth. Catal. 2012, 354,
133. (c) Nakamura, I.; Sato, T.; Yamamoto, Y. Angew. Chem., Int. Ed.
2006, 45, 4473.
ASSOCIATED CONTENT
■
S
* Supporting Information
(5) Zhang, L. J. Am. Chem. Soc. 2005, 127, 16804.
(6) Dube, P.; Toste, F. D. J. Am. Chem. Soc. 2006, 128, 12062.
́
(7) (a) Nakamura, I.; Yamagishi, U.; Song, D.; Konta, S.; Yamamoto,
Y. Chem.Asian J. 2008, 3, 285. (b) Nakamura, I.; Yamagishi, U.;
Song, D.; Konta, S.; Yamamoto, Y. Angew. Chem., Int. Ed. 2007, 46,
2284.
1H and 13C NMR spectra for all starting materials and products
and CIF files and ORTEP drawings of 1b, 2b, and NHC−
gold(I) complex E. This material is available free of charge via
the Internet at http://pubs.acs.org.
(8) Yeon, H.-S.; So, E.; Shin, S. Chem.−Eur. J. 2011, 17, 1764.
(9) Rao, W.; Susanti, D.; Chan, P. W. H. J. Am. Chem. Soc. 2011, 133,
15248.
(10) For the only other examples of a heteroatom or transmetalation-
triggered deaurative process in gold catalysis, see: (a) Chen, Y.; Chen,
M.; Liu, Y. Angew. Chem., Int. Ed. 2012, 51, 6181. (b) Hopkinson, M.
N.; Giuffredi, G. T.; Gee, A. D.; Gouverneur, V. Synlett 2010, 2737.
(c) Schuler, M.; Silva, F.; Bobbio, C.; Tessier, A.; Gouverneur, V.
Angew. Chem., Int. Ed. 2008, 47, 7927. (d) Nakamura, I.; Sato, T.;
Terada, M.; Yamamoto, Y. Org. Lett. 2007, 9, 4081.
(11) For selected examples, see ref 9 and: (a) Rao, W.; Sally; Koh, M.
J.; Chan, P. W. H. J. Org. Chem. 2013, 78, 3183. (b) Rao, W.; Koh, M.
J.; Kothandaraman, P.; Chan, P. W. H. J. Am. Chem. Soc. 2012, 134,
10811. (c) Kothandaraman, P.; Huang, C.; Susanti, D.; Rao, W.; Chan,
P. W. H. Chem.−Eur. J. 2011, 17, 10081. (d) Kothandaraman, P.;
Mothe, S. R.; Toh, S. S. M.; Chan, P. W. H. J. Org. Chem. 2011, 76,
7633. (e) Kothandaraman, P.; Rao, W.; Foo, S. J.; Chan, P. W. H.
Angew. Chem., Int. Ed. 2010, 49, 4619.
AUTHOR INFORMATION
Corresponding Author
*E-mail: waihong@ntu.edu.sg.
Notes
■
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
This work is supported by a College of Science Start-Up Grant
from Nanyang Technological University and an A*STAR-
MSHE Joint Grant (122 070 3062) from A*STAR, Singapore.
A Yousef Jameel Scholarship (to W.T.T.) is gratefully
acknowledged, and we thank Drs. Yongxin Li and Rakesh
Ganguly of this Division for providing the X-ray crystallo-
graphic data reported in this work.
REFERENCES
■
(12) (a) Barabe,
Lett. 2011, 13, 5580. (b) Lop
Chem. Soc. 2010, 132, 9292. (c) Amijs, C. H. M.; Lop
Raducan, M.; Perez-Galan, P.; Ferrer, C.; Echavarren, A. M. J. Org.
́
F.; Levesque, P.; Korobkov, L.; Barriault, L. Org.
ez-Carrillo, V.; Echavarren, A. M. J. Am.
ez-Carrillo, V.;
(1) For selected general reviews on gold catalysis, see: (a) Rudolph,
M.; Hashmi, A. S. K. Chem. Soc. Rev. 2012, 41, 2448. (b) Garayalde,
D.; Nevado, C. ACS Catal. 2012, 2, 1462. (c) Krause, N.; Winter, C.
Chem. Rev. 2011, 111, 1994. (d) Corma, A.; Leyva-Per
M. J. Chem. Rev. 2011, 111, 1657. (e) Furstner, A. Chem. Soc. Rev.
́
́
́
́
́
ez, A.; Sabater,
Chem. 2008, 73, 7721. (d) Richard, L.; Gagosz, F. Organometallics
2007, 26, 4704.
̈
2009, 38, 3208. (f) Abu Sohel, S. M.; Liu, R.-S. Chem. Soc. Rev. 2009,
I
dx.doi.org/10.1021/jo401083m | J. Org. Chem. XXXX, XXX, XXX−XXX

The Journal of Organic Chemistry
Article
(13) For selected examples of sulfonyl group migrations mediated by
other Lewis and Brønsted acids or a base, see: (a) Yu, X.; Xin, X.;
Wan, B.; Li, X. J. Org. Chem. 2013, 78, 4895. (b) Prasad, B.; Adepu, R.;
Sandra, S.; Rambabu, D.; Krishna, G. R.; Reddy, C. M.; Deora, G. S.;
Misra, P.; Pal, M. Chem. Commun. 2012, 48, 10434. (c) Xin, X.; Wang,
D.; Li, X.; Wan, B. Angew. Chem., Int. Ed. 2012, 51, 1693. (d) Lee, Y.
T.; Chung, Y. K. J. Org. Chem. 2008, 73, 4698. (e) Weatherhead-
Kloster, R. A.; Corey, E. J. Org. Lett. 2006, 8, 171. (f) Matsumoto, S.;
Kishimoto, T.; Ogura, K. Chem. Lett. 2002, 134.
(14) CCDC 918205 (E) contains the supplementary crystallographic
data for this Article. These data can be obtained free of charge from
the Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/
data_request/cif.
(15) CCDC 918206 (1b) contains the supplementary crystallo-
graphic data for this Article. These data can be obtained free of charge
from the Cambridge Crystallographic Data Centre via www.ccdc.cam.
ac.uk/data_request/cif.
(16) CCDC 918207 (2b) contains the supplementary crystallo-
graphic data for this Article. These data can be obtained free of charge
from the Cambridge Crystallographic Data Centre via www.ccdc.cam.
ac.uk/data_request/cif.
J
dx.doi.org/10.1021/jo401083m | J. Org. Chem. XXXX, XXX, XXX−XXX