Indium(III)-Catalyzed Cyclization of Aromatic 5-Enynamides: Facile Synthesis of 2-Aminonaphthalenes, 2-Amino-1H-indenes, and 2,3-Dihydro-1H-indeno[2,1-b]pyridines

Article abstract of DOI:10.1002/adsc.201500449

Indium(III)-catalyzed cyclization reactions of aromatic 5-enynamides were studied. Indium triflate enabled the efficient synthesis of 2-aminonaphthalenes and 2-amino-1H-indenes from aromatic N-methyl-N-tosyl-ynamides bearing an ortho-vinyl and -isobutenyl group, respectively. The aromatic N-3-arylpropargylynamides bearing an ortho-gem-dihalovinyl subunit underwent a tandem cyclization/carbobromination reaction in the presence of indium tribromide to provide the dibrominated 2,3-dihydro-1H-indeno[2,1-b]pyridine derivatives in good yields.

Full text of DOI:10.1002/adsc.201500449

FULL PAPERS
DOI: 10.1002/adsc.201500449
Indium(III)-Catalyzed Cyclization of Aromatic 5-Enynamides:
Facile Synthesis of 2-Aminonaphthalenes, 2-Amino-1H-indenes,
and 2,3-Dihydro-1H-indeno[2,1-b]pyridines
Ming-Chang P. Yeh,a,* Chia-Jung Liang,a Hsiao-Feng Chen,a and Yu-Ting Wenga
a
Department of Chemistry, National Taiwan Normal University, 88 Ding-Jou Road, Section 4, Taipei 11677, Taiwan,
Republic of China
Fax: (+886)-2-2932-4249; e-mail: cheyeh@ntnu.edu.tw
Received: May 6, 2015; Revised: July 30, 2015; Published online: October 14, 2015
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/adsc.201500449.
Abstract: Indium(III)-catalyzed cyclization reactions vinyl subunit underwent a tandem cyclization/carbo-
of aromatic 5-enynamides were studied. Indium tri- bromination reaction in the presence of indium tri-
flate enabled the efficient synthesis of 2-aminonaph- bromide to provide the dibrominated 2,3-dihydro-
thalenes and 2-amino-1H-indenes from aromatic N- 1H-indeno[2,1-b]pyridine derivatives in good yields.
methyl-N-tosyl-ynamides bearing an ortho-vinyl and
-isobutenyl group, respectively. The aromatic N-3-ar-
ylpropargylynamides bearing an ortho-gem-dihalo- Keywords: amides; bromine; cyclization; indium
Introduction
indenes were available in excellent yields from the
cyclization of aromatic ynamides with an ortho-isobu-
In recent years, ynamides have emerged as versatile tenyl group. Moreover, the reaction of aromatic N-3-
building blocks in organic synthesis.[1] Reactive kete- arylpropargyl-ortho-gem-dibromovinyl-ynamides with
niminium ions, generated in situ from the reaction of InBr3 proceeded via a tandem enynamide cyclization/
ynamides with a metal catalyst or an acid, are strong carbobromination to furnish the dibrominated 2,3-di-
electrophilic anchors for cyclization with p-nucleo- hydro-1H-indeno[2,1-b]pyridine derivatives.
philes, providing an easy access to a variety of useful
nitrogen-containing heterocycles.[2] Many transition
metal catalysts, including Rh,[3] Pd,[4] Pt,[5] Cu,[6] Ag,[7] Results and Discussion
Co,[8] and gold,[9] have been employed for intramolec-
ular cyclization of ynamides with an alkene or alkyne. Various synthetic methods for the synthesis of yn-
In contrast to various transition metal-catalyzed cycli- amides have been documented.[13] The aromatic 5-en-
zation reactions, acid-promoted intramolecular cycli- ynamide 1a, as the cyclization precursor, was pre-
À
zations of ynamides with tethered unsaturated C C pared starting from 2-bromobenzaldehyde (see the
bonds were limited to the HNTf2-catalyzed cyclization Supporting Information for details)[14] and was treated
of aromatic ynamides,[10a] the TsOH-catalyzed cycliza- with a range of Brønsted and Lewis acids (Table 1).
tion of ynamides with an alkyne,[10b] the AgOTf-cata- Our first optimization study consisted of subjecting
lyzed cycloisomerization reactions of heteroaromatic 5 mol% of HNTf2 to a solution of the 5-enynamide 1a
ynamides[11a] and epoxy ynamides,[11b] and the in CH2Cl2 (DCM) at 308C. After 2 min, 1a led to the
BF3·OEt2-promoted intramolecular ring-closing meta- 2-aminonaphthalene derivative 2a in 69% yield
thesis of ynamides bearing an aldehyde.[12] In this (Table 1, entry 1). On the other hand, reaction of 1a
report, we describe our results on a simple catalytic with TfOH (5 mol%) in DCM at room temperature
process that transforms aromatic 5-enynamides, in the for 3 d produced 2a in only 32% yield (Table 1,
presence of a catalytic amount of InX3 (X=OTf or entry 2). Next, the use of 5 mol% of the Au(I) cation,
Br), into nitrogen-containing bi- and tricycles. Under formed in situ from AuCl(PPh3) and AgOTf, in DCM
mild reaction conditions, aromatic ynamides bearing at room temperature for 5 d led to a 49% yield of 2a
a vinyl group at the ortho position of the phenyl ring (Table 1, entry 3). It has been known that AgOTf is
afforded 2-aminonaphthalenes, whereas 2-amino-1H- capable of catalyzing intramolecular hydroarylation
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Indium(III)-Catalyzed Cyclization of Aromatic 5-Enynamides
Table 1. Screen of catalysts for the formation of 2-amino-
naphthalene 2a.[a]
Table 2. Screen of catalysts for the formation of 2-amino-
1H-indene 4a.[a]
[a]
Reaction conditions: 1a (0.25 mmol), catalyst (1.25”
10À2 mmol), DCM (2.5 mL).
[a]
Reaction conditions: 3a (0.25 mmol), catalyst (1.25”
[b]
10À2 mmol), DCM (2.5 mL).
Yields obtained from column chromatography over silica
[b]
gel.
Yields obtained from column chromatography over silica
[c]
In(OTf)3 (3 mol%) was used.
gel.
of aromatic ynamide-tethered pyrroles to afford pyr- (10 min, 44%), and InBr3 (10 min, 60%), were capa-
rolo[1,2-a]quinolines in good yields.[11a] However, ble of transforming 3a into 4a (Table 2 entries 2–9),
when subjected to 5 mol% of AgOTf in DCM for 2 d, 0.05 molar equiv. of In(OTf)3 in DCM at room tem-
1a delivered 2a in only 47% yield (Table 1, entry 4). perature for 10 min were the optimal reaction condi-
Other Lewis acids (5 mol%), including Fe(OTf)3, tions, which delivered 4a in 98% isolated yield. There-
Sc(OTf)3, and Sn(OTf)2, were capable of promoting fore, In(OTf)3 was chosen as the catalyst of perform-
the cycloisomerization reaction to produce 2a in 71– ing the cycloisomerization reactions for both starting
76% yields (Table 1, entries 5–7). To our delight, substrates 1 and 3.
when 1a was treated with 5 mol% of In(OTf)3 in
Having identified the optimal reaction conditions
DCM at room temperature for 8 h, 2a was isolated in for the synthesis of 2-aminonaphthalene derivative 2a
94% yield (Table 1, entry 8). With a lower loading of and 2-amino-1H-indene derivative 4a, a survey of var-
In(OTf)3 (3 mol%) in DCM, the reaction required ious substrates was conducted to evaluate the scope
a prolonged reaction time (13 h) but still provided 2a and limitation of the cycloisomerization reactions. Re-
in 75% yield (Table 1, entry 9). Unfortunately, the cy- sults are summarized in Scheme 1 and Scheme 2, re-
cloisomerization reaction failed in the presence of spectively. Unlike the parent substrate 1a requiring
InCl3 and the reactant 1a was recovered quantitative- a lengthy reaction time, aromatic 5-enynamides 1b–g,
ly. (Table 1, entry 10).
having an alkyl or aryl group substituent at the inter-
Next, the aromatic ortho-isobutenyl-substituted nal olefin carbon, were more reactive and afforded
enynamide 3a was investigated. Interestingly, treat- the corresponding 2-aminonaphthalene derivatives
ment of 3a with a catalytic amount of In(OTf)3 2b–g[15] in minutes (2–13 min) and in excellent yields
(5 mol%) in DCM at room temperature under nitro- (85–99%). Compound 1h bearing a benzyl protecting
gen for 10 min afforded a compound identified as the group on the nitrogen atom also cyclized efficiently to
2-amino-1H-indene derivative 4a in 98% isolated generate the desired product 2h in 9 min and in 98%
yield after column chromatography over silica gel yield. The halogenated aromatic 5-enynamides, 1i and
(Table 2, entry 1). Although various acids, including 1j, were also reactive and afforded quantitatively the
FeCl3 (10 min, 74%), Yb(OTf)3 (10 d, 84%), Sn(OTf)2 desired cyclization products 2i and 2j, respectively.
(10 min, 74%), NHTf2 (45 min, 55%), In(NTf2)3 The ortho-vinyl-tethered thiophenylynamides 1k–m
(10 min, 67%), SnCl4 (10 min, 51%), BF3·OEt2 were also tolerated and cycloisomerized to the corre-
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Scheme 2. Substrate scope of the In(OTf)3-catalyzed cyclo-
isomerization of 3. Reaction conditions: 3 (0.25 mmol),
In(OTf)3 (1.25”10À2 mmol), DCM (2.5 mL); isolated yields.
Figure 1. Structures of 2n, 2o, and 4j.
an aqueous work-up and column chromatography
over silica gel. Moreover, substrate 1o, bearing an N-
Boc(Ph) group, was subjected to 3 mol% In(OTf)3 in
DCM. The cycloisomerization reaction required
70 min and afforded 2-aminonaphthalene derivative
2o (Figure 1) in 64% isolated yield. Furthermore, it
should be noted that an important gold(I)-catalyzed
cyclization of aromatic ynamides with ethoxyethene
was also known to afford 2-aminonaphthalenes in
good yields.[17]
Scheme 1. Substrate scope of the In(OTf)3-catalyzed cyclo-
isomerization of 1. Reaction conditions: 1a (0.25 mmol),
In(OTf)3 (7.5”10À3 mmol), DCM (2.5 mL); isolated yields.
sponding 5-aminobenzo[b]thiophenes 2k–m[15] in 75–
As revealed in Scheme 2, aromatic ortho-isobuten-
95% yields. To explore the possibility of deprotecting yl-substituted enynamides 3a–d bearing an electron-
the N-tosyl group, compound 2d was treated with neutral or electron-rich substituent on the phenyl ring
sodium/naphthalene in THF at À788C.[16] The reac- were equally reactive and produced the desired 2-
tion was stirred for 30 min and delivered 4-phenyl-2- amino-1H-indenes 4a–d[15] in excellent yields (90–
aminonaphthalene (2n) (Figure 1) in 54% yield after 98%). It is noteworthy that a fluorine or chlorine
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Indium(III)-Catalyzed Cyclization of Aromatic 5-Enynamides
Scheme 3. Postulated reaction paths for the formation of 2 and 4.
atom on the phenyl ring did not interfere with the re- ophiles with alkynes for the construction of various
activity of the catalyst and 3e and 3f delivered 4e and carbocycles and heterocycles have also been stud-
4f in 93 and 99% yield, respectively. Switching the ied.[19]
methyl protecting group to a benzyl (3g) or n-butyl
Next, substrate 8 possessing an ortho-gem-dibromo-
group (3h) on the nitrogen atom did not show any in- vinyl subunit was investigated for the intramolecular
fluence on the cyclization. The corresponding 2- cyclization reaction. Among the Lewis acids
amino-1H- indene derivatives 4g[15] and 4h were iso- [In(OTf)3, FeCl3, InBr3, and AuCl(PPh3)/AgOTf]
lated in respectively 94 and 95% yield. The 5-amino- screened, InBr3 was found to have a promising ten-
cyclopenta[b]thiophene derivative 4i was also avail- dency to yield 1-tribromomethyl-2-amino-1H- indene
able in quantitative yield from the ortho-isobutenyl- derivative 9. Thus, treatment of 8a with 1.2 molar e-
substituted thiophenylynamide 3i. When treated with quiv. of InBr3 at room temperature under nitrogen for
0.05 equiv. of In(OTf)3 in DCM, substrate 3j, bearing 10 min produced the carbobromination product 9a[15]
an N-Boc(Ph) tether, also gave the corresponding 2- in 60% yield (Scheme 4). Substrate 8b bearing a fluo-
amino-1H-indene derivatives 4j (Figure 1) in 2 min rine at C-5 of the phenyl ring also gave the corre-
and in 51% isolated yield. The current synthetic sponding 1-tribromomethyl-2-amino-1H- indene 9b in
method employing a catalytic amount of In(OTf)3 55% yield. In this transformation, the activation of 8a
with the ortho-isobutenyl-tethered ynamides provides with InBr3 would form the reactive keteniminium in-
a good alternative to 3-alkenyl-substituted 2-aminoin- termediate 10 (Scheme 5). Attack of the gem-dibro-
denes, which may be applied to the synthesis of bioac- movinyl group at the a-carbon of the keteniminium
tive molecules.[18]
ion 10 generated the transient carbonium ion. Addi-
Formation of 2-aminonaphthalene 2a and 2-amino- tion of a bromide to the cation center followed by
1H-indene 4a can be explained by reaction paths de-
picted in Scheme 3. First, metalation of the electron-
rich alkyne of the enynamide 1a with In(OTf)3 would
form a reactive keteniminium ion 5. Attack of the
vinyl group at the a-position of 5a (R=H) via a 6-
exo-dig fashion gives the benzylic cation 6, which un-
dergoes deprotonation followed by protodemetalation
to produce 2a, whereas a 5-exo-dig cyclization of 5b
(R=CH3) occurred, leading to the tertiary cationic
intermediate 7, which produces 4a after deprotona-
tion followed by protodemetalation. In both cases, the
weakly nucleophilic anion (TfOÀ, the conjugated
base) does not add to the keteniminium ion 5 or at
carbocation centers of 6 and 7. It is worth mentioning
Scheme 4. Synthesis of 1-tribromomethyl-2-amino- 1H-in-
denes 9a and 9b. Reaction conditions: 8 (0.20 mmol), InBr3
that In(III)-promoted cyclization reactions of p-nucle- (0.24 mmol), DCM (2.0 mL); isolated yields.
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Ming-Chang P. Yeh et al.
Scheme 5. Suggested mechanism for the formation of 9a.
protodemetalation during an aqueous process fur-
nished 1-tribromomethyl-2-amino-1H-indene deriva-
tive 9a. Unfortunately, substrate 8c, bearing an N-
Boc(Ph) group, decomposed upon treatment with
InBr3 under the same reaction conditions. Interesting-
ly, when switching the alkyl protecting group to a 3-
phenylpropargyl moiety on the nitrogen atom, for ex-
ample 11a, a consecutive cyclization occurred to fur-
nish the dibrominated 2,3-dihydro-1H-indeno[2,1-
b]pyridine derivative 12a (Scheme 6). Thus, treatment
of 11a with 1.2 equiv. of InBr3 in DCM at 308C for
10 min gave a 42% isolated yield of 12a.[15] Com-
pound 12 may have potential applications in medici-
nal chemistry since several indeno[2,1-b]pyridine-
based compounds have been reported to possess phar-
macological activities.[20] Further optimization studies
had shown that the yield of 12a increased to 78%
when 11a was treated with 0.5 molar equiv. of InBr3
in dichloroethane (DCE) at a higher temperature
(808C). Next, a series of aromatic N-3-arylpropargyl-
ortho-gem-dibromovinyl-ynamides, 11b–i, were sub-
mitted to the tandem cyclization conditions employ-
Scheme 6. Synthesis of the dibrominated 2,3-dihydro-1H-
indeno[2,1-b]pyridine derivatives 12. Reaction conditions: 11
(0.2 mmol), InBr3 (0.1 mmol), DCE (20 mL), 808C; isolated
yields.
ing 0.5 molar equiv. of InBr3 at 808C in DCE and the desired products in low yields (46–64%). Unfortu-
results are shown in Scheme 6. The cyclization pro- nately, substrate 11j, with an n-butyl substituent at
ceeded smoothly with electron-neutral and electron- the terminus of the alkyne, gave an unidentified mix-
deficient 3-arylpropargyl groups to give the desired ture of compounds.
cyclization products in yields ranging from 60–78%
(12a–d). Substrates with a halogen atom at the phenyl representative
A suggested reaction path for the formation of the
dibrominated 2,3-dihydro-1H-
group, 11e and 11f, were also operative and delivered indeno[2,1-b]pyridine 12a from 11a is shown in
12e and 12f in 93 and 62% yield, respectively. Sub- Scheme 7. The reactive keteniminium cation 13, gen-
strates 11g–i, containing electron-donating methyl and erated from metalation of the ynamide, was attacked
methoxy substituents on the phenyl ring, afforded the by the pendant dibromoalkene by a 5-exo-dig cycliza-
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Indium(III)-Catalyzed Cyclization of Aromatic 5-Enynamides
Conclusions
In conclusion, this report demonstrates a convenient
method for the synthesis of 2-aminonaphthalenes and
2-amino-1H-indenes from aromatic ortho-alkenyl-yn-
amides employing indium triflate as the catalyst. The
dibrominated 2,3-dihydro-1H-indeno[2,1-b]- pyridines
are available from indium tribromide-promoted en-
ynamide cyclization/carbobromination of aromatic
N-3-arylpropargyl-ortho-gem-dihalo-vinylynamides.
These reactions have advantages as they involve
milder reaction conditions, short reaction times, and
good to excellent yields. Especially, the facile ap-
proach to the dibrominated 2,3-dihydro-1H-
indeno[2,1-b]pyridine derivatives from easily available
starting substrates may have further applications.
Experimental Section
Typical Procedure for the Preparation of N,4-
Dimethyl-N-(naphthalen-2-yl)benzenesulfonamide
(2a) in Dichloromethane
Scheme 7. Mechanism for the formation of the dibrominated
1H-indeno[2,1-b]pyridine derivative 12a.
To a solution of N,4-dimethyl-N-[(2-vinylphenyl)ethynyl]-
benzenesulfonamide (1a) (78 mg, 0.25 mmol) in dichlorome-
thane (2.5 mL) was added In(OTf)3 (4.0 mg, 0.0075 mmol)
at room temperature under nitrogen. The reaction mixture
was stirred until no trace of 1a was detected on TLC, and
concentrated under reduced pressure to give a crude oil.
The resulting crude mixture was purified by flash column
chromatography [silica gel, 5% EtOAc in hexanes] to afford
product 2a as a pale yellow oil; yield: 58 mg (0.19 mmol,
75%).
The products 2b–m were prepared in a similar manner.
N,4-Dimethyl-N-(naphthalen-2-yl)benzenesulfonamide
(2a): yield: 58 mg (0.19 mmol, 75%); yellow oil; IR
(CH2Cl2): n=3055, 2925, 1598, 1466, 1356, 1162, 819, 752,
672 cmÀ1 1H NMR (400 MHz, CDCl3): d=7.82 (m, 1H),
;
7.77 (d, J=8.8 Hz, 1H), 7.72 (m, 1H), 7.51–7.46 (m,3H),
7.43 (d, J=8.3 Hz, 2H), 7.30 (dd, J=8.8, 2.2 Hz, 1H) 7.21
(d, J=8.2 Hz, 2H), 3.26 (s, 3H), 2.41 (s, 3H); 13C NMR
(100 MHz, CDCl3): d=143.6, 139.2, 133.5, 133.2, 132.1, 129.3
(2C), 128.6, 127.9 (2C), 127.9, 127.6, 126.4, 126.3, 125.1,
124.6, 38.2, 21.5; MS (APCI): m/e (%)=312.1 ([M+H]+,
100), 249.2 (1), 198.1 (2), 157.1 (4); HR-MS (APCI): m/e=
312.1055, calcd. for C18H18NO2S [M+H]+: 312.1058.
Scheme 8. Synthesis of the dichlorinated 2,3-dihydro-1H-
indeno[2,1-b]pyridine derivatives 17.
tion to afford the cation 14. Then, an anti-addition of
a bromide and the carbonium ion across the alkyne
N,4-Dimethyl-N-(4-methylnaphthalen-2-yl)benzenesulfon-
occurred, giving the tribrominated compound 15, amide (2b): yield: 80 mg (0.25 mmol, 98%) white solid; mp
88–898C; IR (CH2Cl2): n=3064, 2924, 1600, 1466, 1350,
which underwent dehydrobromination followed by
protodemetalation to furnish the dibrominated 2,3-di-
hydro-1H- indeno[2,1-b]pyridine derivative 12a.
The cyclization reactions were also effective with
aromatic N-3-arylpropargyl-ortho-gem-dichlorovinyl-
ynamides 16a–f, albeit in slightly lower yields. Thus,
treatment of ynamides 16a–f with 0.5 molar equiv. of
InCl3 in DCE (0.01M) at 808C for 45 min generated
the desired products 17a–f[15] in 50–72% yields
(Scheme 8).
1
1170, 876, 806, 666 cmÀ1; H NMR (400 MHz, CDCl3): d=
7.95 (d, J=8.4 Hz, 1H), 7.70 (d, J=8.2 Hz, 1H), 7.54–7.46
(m, 2H), 7.45 (d, J=8.3 Hz, 2H), 7.28 (s, 1H), 7.24–7.18 (m,
3H), 3.23 (s, 3H), 2.64 (s, 3H), 2.41(s, 3H); 13C NMR
(100 MHz, CDCl3): d=143.5, 138.8, 135.4, 133.6, 133.4,
131.4, 129.3 (2C), 128.5, 127.9 (2C), 126.1, 126.1,126.0,
123.9, 122.6, 38.3, 21.5, 19.3; MS (ESI): m/e (%)=326.05
([M+H]+, 100), 321.17 (9), 171.21 (32), 154.16 (2); HR-MS
(ESI): m/e=326.1220, calcd. for C19H20NO2S [M+H]+:
326.1215.
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N-(4-Butylnaphthalen-2-yl)-N,4-dimethylbenzenesulfona-
mide (2c): yield: 91 mg (0.25 mmol, 99%); pale yellow solid;
mp 76–778C; IR (CH2Cl2): n=3063, 2929, 2872, 1599, 1459,
J=3.2 Hz, 1H), 7.92 (d, J=3.2 Hz, 1H), 7.88 (d, J=8.3 Hz,
1H), 7.80 (d, J=2.1 Hz, 1H), 7.56 (dd, J=8.2, 7.1 Hz, 1H),
7.52–7.45 (m, 4H), 7.38 (dd, J=7.0, 1.1 Hz, 1H), 7.36–7.26
(m, 4H), 7.19 (d, J=8.2 Hz. 2H), 7.12 (d, J=2.2 Hz, 1H),
3.29 (s, 3H), 2.35 (s, 3H); 13C NMR (100 MHz, CDCl3): d=
143.6, 139.4, 138.3, 137.4, 133.7, 133.5 (2C), 132.5, 131.7,
129.4 (2C), 128.4, 128.2, 128.2, 127.9 (2C), 127.7, 126.5,
126.5, 126.4, 126.3, 126.1, 125.9, 125.8, 125.5, 125.2, 38.2,
21.5; MS (ESI): m/e (%)=438.06 ([M+H]+, 100), 284.33
(16), 283.29 (65), 282.28 (15), 267.49 (4); HR-MS (ESI):
m/e=438.1528, calcd. for C28H24NO2S [M+H]+: 438.1528.
N-Benzyl-4-methyl-N-(4-phenylnaphthalen-2-yl)benzene-
sulfonamide (2h): yield: 114 mg (0.25 mmol, 98%); yellow
solid; mp 56–588C; IR (CH2Cl2): n=3062, 3032, 2924, 1597,
1
1349, 1171, 808, 663 cmÀ1; H NMR (400 MHz, CDCl3): d=
8.00 (d, J=8.3 Hz,1H), 7.73 (d, J=8.5 Hz, 1H), 7.53–7.45
(m, 2H), 7.44 (d, J=8.2 Hz, 2H), 7.35 (d, J=2.1 Hz, 1H),
7.21 (d, J=8.0 Hz, 2H), 7.11 (d, J=2.1 Hz, 1H), 3.25 (s,
3H), 3.00 (t, J=7.8 Hz, 2H), 2.40 (s, 3H), 1.72–1.58 (m,
2H), 1.40 (sextet, J=7.44 Hz, 2H), 0.95 (t, J=7.3 Hz, 3H);
13C NMR (100 MHz, CDCl3): d=143.4, 140.1, 138.7, 133.8,
133.7, 130.8, 129.3 (2C), 128.8, 127.9 (2C), 126.1, 126.0,
124.9, 123.7, 123.0, 38.2, 32.7, 32.5, 22.7, 21.5, 14.0; MS
(FAB): m/e (%)=368.1 ([M+H]+, 100), 367.1 (84), 303.2
(41), 228.2 (6), 212.2 (81), 129.1 (8); HR-MS (FAB): m/e=
368.1689, calcd. for C22H26NO2S [M+H]+: 368.1684.
1455, 1348, 1160, 919, 750, 703 cmÀ1 1H NMR (400 MHz,
;
N,4-Dimethyl-N-(4-phenylnaphthalen-2-yl)benzenesulfon-
amide (2d): yield: 95 mg (0.25 mmol, 98%); yellow solid;
mp 153–1558C; IR (CH2Cl2): n=3061, 2922, 1596, 1448,
CDCl3): d=7.79 (d, J=8.2 Hz, 1H), 7.74 (d, J=8.0 Hz, 1H),
7.58 (d, J=8.1 Hz, 2H), 7.55 (s, 1H), 7.47–7.36 (m, 5H),
7.27 (d, J=6.1 Hz, 6H), 7.23–7.13 (m, 3H), 6.95 (d, J=
1.9 Hz, 1H), 4.83 (s 2H), 2.43 (s, 3H); 13C NMR (100 MHz,
CDCl3): d=143.6, 141.0, 139.7, 136.0, 135.8, 135.7, 133.7,
130.7, 129.9 (2C), 129.5 (2C), 128.5, 128.5 (2C), 128.4 (2C),
128.2 (2C), 127.8 (3C), 127.6, 127.5, 127.0, 126.6, 126.2,
125.7, 54.7, 21.5; MS (FAB): m/e (%)=464.1 ([M+H]+,
100), 463.1 (72), 399.2 (25), 308.2 (87), 231.1 (10), 202.1
(15); HR-MS (FAB): m/e=464.1677, calcd. for C30H26NO2S
[M+H]+: 464.1684.
1
1352, 1169, 920, 786, 704 cmÀ1; H NMR (400 MHz, CDCl3):
d=7.86 (d, J=8.3 Hz, 1H), 7.81 (d, J=7.9 Hz, 1H), 7.58 (d,
J=2.0 Hz, 1H), 7.52–7.36 (m, 9H), 7.23 (d, J=8.1 Hz, 2H),
7.15 (d, J=2.1 Hz, 1H), 3.27 (s, 3H), 2.42 (s, 3H); 13C NMR
(100 MHz, CDCl3): d=143.6, 141.2, 139.8, 138.5, 133.8,
133.7, 130.5, 129.9 (2C), 129.4 (2C), 128.4, 128.3 (2C), 128.0
(2C), 127.5, 126.5, 126.4, 125.9, 125.7, 124.6, 38.3, 21.5; MS
(APCI): m/e (%)=388.1 ([M+H]+, 100), 343.1 (10), 311.1
(42), 223.1 (21), 186.1 (9), 122.0 (6); HR-MS (APCI): m/e=
388.1380, calcd. for C24H22NO2S [M+H]+: 388.1371.
N-(6-Fluoro-4-phenylnaphthalen-2-yl)-N,4-dimethylben-
zenesulfonamide (2i): yield: 100 mg (0.25 mmol, 99%);
white solid; mp 172–1738C; IR (CH2Cl2): n=3060, 2926,
N,4-Dimethyl-N-(4-(p-tolyl)naphthalen-2-yl)benzenesul-
fonamide (2e): yield: 78 mg (0.23 mmol, 92%); pale yellow
solid; mp 129–1308C; IR (CH2Cl2): n=3050, 2923, 1597,
1600, 1350, 1169, 948, 757 cmÀ1
;
1H NMR (400 MHz,
CDCl3): d = 7.81 (dd, J=9.0, 5.8 Hz, 1H), 7.60 (d, J=
2.0 Hz, 1H), 7.52–7.40 (m, 6H), 7.39–7.32 (m, 2H), 7.30–
7.22 (m, 3H), 7.15 (d, J=2.0 Hz, 1H), 3.26 (s, 3H), 2.42 (s,
3H); 13C NMR (100 MHz, CDCl3): d=161.2 (d, J=246 Hz),
143.7, 140.6 (d, J=6 Hz), 139.3, 137.9 (d, J=3 Hz), 133.6,
131.5 (d, J=9 Hz), 130.8 (d, J=9 Hz), 130.7, 129.7 (2C),
129.4 (2C), 128.5 (2C), 128.0 (2C), 127.8, 126.5, 124.7, 116.8
(d, J=26 Hz), 119.4 (d, J=22 Hz), 38.2, 21.5; 19F NMR
(376 MHz, CDCl3): d=À113.7; MS (ESI): m/e (%)=406.0
([M+H]+, 100), 374.6 (4), 251.3 (64), 230.90 (3); HR-MS
(ESI): m/e=406.1277, calcd. for C24H21NO2FS [M+H]+:
406.1277.
1
1351, 1168, 922, 823, 663 cmÀ1; H NMR (400 MHz, CDCl3):
d=7.88 (d, J=8.4 Hz, 1H), 7.80 (d, J=7.8 Hz, 1H), 7.58 (d,
J=2.1 Hz, 1H), 7.53–7.45 (m, 3H), 7.42 (ddd, J=8.3, 6.8,
1.3 Hz, 1H), 7.28 (s, 4H), 7.23 (d, J=8.1 Hz, 2H), 7.11 (d,
J=2.2 Hz, 1H), 3.26 (s, 3H), 2.44 (s, 3H), 2.42 (s, 3H);
13C NMR (100 MHz, CDCl3): d=143.6, 141.2, 138.5, 137.3,
136.8, 133.8, 133.7, 130.6, 129.8 (2C), 129.4 (2C), 129.0 (2C),
128.4, 128.0 (2C), 126.4, 126.3, 125.9, 125.6, 124.5, 38.3, 21.5,
21.2; MS (FAB): m/e (%)=402.1 ([M+H]+, 100), 377.2
(40), 296.2 (10), 247.2 (96), 246.2 (87), 205.1 (28); HR-MS
(FAB): m/e=402.1518, calcd. for C25H24NO2S [M+H]+:
402.1528.
N-[6-Chloro-4-phenylnaphthalen-2-yl]-N,4-dimethylben-
zenesulfonamide (2j): yield: 104 mg (0.25 mmol, 99%);
white oil; IR (CH2Cl2): n=3058, 2926, 1736, 1593, 1351,
N-{4-([1,1’-Biphenyl]-4-yl)naphthalen-2-yl}-N,4-dimethyl-
benzenesulfonamide (2f): yield: 97 mg (0.24 mmol, 97%);
yellow solid; mp 89–918C; IR (CH2Cl2): n=3060, 2925,
1
1170, 1089, 928 cmÀ1; H NMR (400 MHz, CDCl3): d=7.82
1598, 1488, 1349, 1168, 922, 845, 711 cmÀ1
;
1H NMR
(d, J=1.9 Hz, 1H), 7.75 (d, J=8.8 Hz, 1H), 7.57 (d, J=
2.1 Hz, 1H), 7.51–7.42 (m, 6H), 7.38–7.34 (m, 2H), 7.24 (d,
J=8.0 Hz, 2H), 7.17 (d, J=2.2 Hz, 1H), 3.26 (s, 3H), 2.42
(s, 3H); 13C NMR (100 MHz, CDCl3): d=143.8, 140.5, 139.1,
138.8, 133.6, 132.6, 132.0, 131.1, 129.9, 129.8 (2C), 129.4
(2C), 128.5 (2C), 127.9 (2C), 127.9, 127.4, 126.6, 124.8,
124.4, 38.1, 21.5; MS (ESI): m/e (%)=423.9 ([M+H+2]+,
37), 421.9 ([M+H]+, 100), 414.6 (10), 356.8 (7), 267.3 (82),
229.2 (5); HR-MS (ESI): m/e=422.0980, calcd. for
C24H21NO2SCl [M+H]+: 422.0982.
(400 MHz, CDCl3): d=7.95 (d, J=8.2 Hz, 1H), 7.83 (d, J=
7.9 Hz, 1H), 7.73–6.65 (m, 4H), 7.60 (d, J=2.1 Hz, 1H),
7.53–7.44 (m, 8H), 7.42– 7.36 (m, 1H), 7.25 (d, J=8.0 Hz,
2H), 7.20 (d, J=2.2 Hz, 1H), 3.29 (s, 3H), 2.43 (s, 3H);
13C NMR (100 MHz, CDCl3): d=143.6, 140.8, 140.7, 140.5,
138.8, 138.6, 133.9, 133.8, 130.5, 130.4 (2C), 129.4 (2C),
128.9 (2C), 128.5, 128.0 (2C), 127.5, 127.1 (2C), 127.0 (2C),
126.6, 126.5, 125.9, 125.8, 124.7, 38.3, 21.6; MS (FAB):
m/e (%)=464.1 ([M+H]+, 100), 463.1 (78), 399.2 (31), 309.2
(76), 308.2 (71), 267.1 (31), 235.2 (13); HR-MS (FAB):
m/e=464.1687, calcd. for C30H26NO2S [M+H]+: 464.1684.
N-([1,1’-Binaphthalen]-3-yl)-N,4-dimethylbenzenesulfona-
mide (2g): yield: 93 mg (0.21 mmol, 85%); white solid; mp
170–1718C; IR (CH2Cl2): n=3061, 2926, 1598, 1351, 1166,
N-(Benzo[b]thiophen-5-yl)-N,4-dimethylbenzenesulfona-
mide (2k): yield: 60 mg (0.19 mmol, 75%); brown solid; mp
101–1028C; IR (CH2Cl2): n=3502, 2926, 2856, 1736, 1597,
1438, 1348, 1165, 938, 846, 814 cmÀ1 1H NMR (400 MHz,
;
CDCl3): d=7.77 (d, J=8.6 Hz, 1H), 7.57 (d, J=2.0 Hz, 1H),
7.48 (d, J=5.4 Hz, 1H), 7.45 (d, J=8.2 Hz, 2H), 7.27 (d, J=
1
917, 791, 666 cmÀ1; H NMR (400 MHz, CDCl3): d=7.95 (d,
3248
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Adv. Synth. Catal. 2015, 357, 3242 – 3254

FULL PAPERS
Indium(III)-Catalyzed Cyclization of Aromatic 5-Enynamides
5.3 Hz, 1H), 7.24 (d, J=8.1 Hz, 2H), 7.05 (dd, J=8.6,
2.0 Hz, 1H), 3.23 (s, 3H), 2.42 (s, 3H); 13C NMR (100 MHz,
CDCl3): d=143.5, 139.9, 138.6, 138.3, 133.5, 129.3 (2C),
128.0 (2C), 127.8, 123.9, 123.0, 122.6, 122.0, 38.6, 21.5; MS
(ESI): m/e (%)=318.0 ([M+H]+, 100), 279.1 (6), 248.6 (4),
163.2 (18); HR-MS (ESI): m/e=318.0623, calcd. for
C16H16NO2S2 [M+H]+: 318.0622.
103.7, 30.8; MS (ESI): m/e (%)=234.2 ([M+H]+, 100),
219.3 (5); HR-MS (ESI): m/e=234.1282, calcd. for C17H16N
[M+H]+: 234.1283.
tert-Butyl naphthalen-2-yl(phenyl)carbamate (2o): yield:
51 mg (0.16 mmol, 64%); white solid; mp 114–1168C; IR
(CH2Cl2): n=2978, 1712, 1596, 1495, 1317, 1163, 748,
693 cmÀ1 1H NMR (400 MHz, CDCl3): d=7.84–7.76 (m,
;
N,4-Dimethyl-N-(7-phenylbenzo[b]thiophen-5-yl)ben-
zenesulfonamide (2l): yield: 84 mg (0.21 mmol, 85%); white
solid;, mp 167–1688C; IR (CH2Cl2): n=3513, 3061, 2933,
2H), 7.76–7.69 (m, 1H), 7.62 (d, J=2.0 Hz, 1H), 7.48–7.41
(m, 2H), 7.39 (dd, J=8.8, 2.1 Hz, 1H), 7.36–7.29 (m, 2H),
7.29–7.22 (m, 2H), 7.22–7.14 (m, 1H), 1.47 (s, 9H);
13C NMR (100 MHz, CDCl3): d=153.9, 143.1, 140.6, 133.5,
131.3, 128.7 (2C), 128.3, 127.7, 127.5, 127.0 (2C), 126.2,
125.9, 125.7, 125.6, 124.8, 81.3, 28.3; MS (ESI): m/e (%)=
342.1 ([M+Na]+, 100), 286.1 (26), 264.2 (22), 218.3 (15);
HR-MS (ESI): m/e=342.1470, calcd. for C21H21NO2Na [M+
Na]+: 342.1470.
1597, 1346, 1169, 895, 701 cmÀ1
;
1H NMR (400 MHz,
CDCl3): d=7.62–7.56 (m, 3H), 7.52–7.44 (m, 5H), 7.44–7.38
(m, 1H), 7.34 (d, J=5.4 Hz, 1H), 7.26 (d, J=7.6 Hz, 2H),
7.03 (d, J=2.0 Hz, 1H), 3.26 (s, 3H), 2.43 (s, 3H); 13C NMR
(100 MHz, CDCl3): d=143.6, 140.5, 139.8, 139.0, 137.8,
136.9, 133.7, 129.4 (2C), 128.8 (2C), 128.2, 128.1 (2C), 128.0
(2C), 127.9, 124.4, 122.9, 121.0, 38.7, 21.5; MS (FAB):
m/e (%)=393.0 ([M]+, 47), 329.1 (15), 238.1 (100), 210.1
(13), 197.1 (10), 165.1 (7); HR-MS (FAB): m/e=393.0857,
calcd. for C22H19NO2S2 [M]+: 393.0857.
Typical Procedure for the Preparation of N,4-
Dimethyl-N-[1-(prop-1-en-2-yl)-1H-inden-2-
yl]benzenesulfonamide (4a) in Dichloromethane
N-Benzyl-4-methyl-N-(7-phenylbenzo[b]thiophen-5-yl)-
benzenesulfonamide (2m): yield: 112 mg (0.24 mmol, 95%);
white oil; IR (CH2Cl2): n=3032, 2926, 1697, 1351, 1164,
To a solution of N,4-dimethyl-N-{[2-(2-methylprop- 1-en-1-
1
1093, 701 cmÀ1; H NMR (400 MHz, CDCl3): d=7.61 (d, J=
yl)phenyl]ethynyl}benzenesulfonamide
(3a,
85 mg,
0.25 mmol) in dichloromethane (2.5 mL) was added
In(OTf)3 (7 mg, 0.012 mmol) at room temperature under ni-
trogen. The reaction mixture was stirred until no trace of 3a
was detected on TLC, then concentrated under reduced
pressure to give a crude liquid. The resulting crude mixture
was purified by flash column chromatography [silica gel,
20% EtOAc in hexanes] to afford product 4a as a yellow
oil; yield: 83 mg (0.25 mmol, 98%).
8.2 Hz, 2H), 7.50–7.42 (m, 6H), 7.42–7.37 (m, 1H), 7.32–
7.16 (m, 8H), 6.87 (d, J=1.8 Hz, 1H), 4.81 (s, 2H), 2.46 (s,
3H); 13C NMR (100 MHz, CDCl3): d=143.5, 140.5, 139.7,
138.2, 136.8, 136.2, 136.0, 135.8, 129.5 (2C), 128.7 (2C),
128.5 (2C), 128.4 (2C), 128.2, 128.0 (2C), 127.9 (2C), 127.7,
127.6, 124.5, 124.4, 123.6, 55.2, 21.5; MS (ESI): m/e (%)=
470.0 ([M+H]+, 100), 447.2 (2), 315.2 (38), 286.2 (3); HR-
MS (ESI): m/e=470.1248, calcd. for C28H24NO2S2 [M+H]+:
470.1248.
The products 4b–i were prepared by the similar manner.
N,4-Dimethyl-N-[1-(prop-1-en-2-yl)-1H-inden-2-yl]ben-
zenesulfonamide (4a): yield: 83 mg (0.25 mmol, 98%);
yellow oil; IR (CH2Cl2): n=3069, 2971, 2356, 1918, 1644,
Procedure for Deprotection of the N-Tosyl Group of
2d; Synthesis of N-Methyl-4-phenylnaphthalen-2-
amine (2n)
1597, 1463, 1358, 1169, 1089, 919, 889, 755, 670, 567 cmÀ1
;
1H NMR (400 MHz, CDCl3): d=7.61 (d, J=8.2 Hz, 2H),
7.26 (d, J=8.0 Hz, 2H), 7.24–7.19 (m, 2H), 7.18–7.11 (m,
2H), 6.23 (s, 1H), 5.24 (s, 1H), 5.09 (s, 1H), 4.74 (s, 1H),
3.11 (s, 3H), 2.41 (s, 3H), 1.22 (s, 3H); 13C NMR (100 MHz,
CDCl3): d=149.7, 143.8, 143.3, 142.6, 142.2, 133,3, 129.5
(2C), 127.7 (2C), 126.9, 124.9, 122.9, 120.3, 119.8, 116.1,
59.7, 37.9, 21.5, 17.2; MS (ESI): m/e (%)=340.1 ([M+H]+,
20), 279.3 (5), 102.1 (5); HR-MS (ESI): m/e=340.1364,
calcd. for C20H22NO2S [M+H]+: 340.1371.
To a flame-dried 25-mL round-bottom flask were added
8 equiv. of sodium (28 mg, 1.2 mmol) and naphthalene
(154 mg, 1.2 mmol) in tetrahydrofuran (0.4 mL) at room
temperature under nitrogen. After 15 min, the solution
turned to a dark-green color. To this solution of sodium
naphthalenide at –788C was added dropwise a solution of
N,4-dimethyl-N-(4-phenylnaphthalen-2-yl)benzenesulfona-
mide (2d, 58 mg, 0.15 mmol) in tetrahydrofuran (0.4 mL).
The reaction mixture was stirred until no trace of 2d was de-
tected on TLC (ca. 30 min). The reaction mixture was then
quenched with 5 drops of saturated aqueous NH4Cl solution
at 08C and concentrated under reduced pressure to give
a crude oil. The resulting crude mixture was purified by
flash column chromatography [silica gel, 5% EtOAc in hex-
anes] to afford product 2n as a yellow oil; yield: 19 mg
(0.08 mmol, 54%).
N,4-Dimethyl-N-[5-methyl-1-(prop-1-en-2-yl)-1H-inden-2-
yl]benzenesulfonamide (4b): yield: 80 mg (0.23 mmol, 90%);
white solid; mp 120–1218C; IR (CH2Cl2): n=3443, 3115,
2920, 2358, 1909, 1597, 1474, 1357, 1170, 803, 670, 571 cmÀ1
;
1H NMR (400 MHz, CDCl3): d=7.60 (d, J=8.3 Hz, 2H),
7.26 (d, J=8.2 Hz, 2H), 7.16 (d, J=7.7 Hz, 1H), 7.01 (s,
1H), 6.97 (d, J=7.7 Hz, 1H), 6.18 (s, 1H), 5.22 (s, 1H), 5.07
(t, J=1.4 Hz, 1H), 4.70 (s, 1H), 3.10 (s, 3H), 2.41 (s, 3H),
2.35 (s, 3H), 1.22 (s, 3H); 13C NMR (100 MHz, CDCl3): d=
149.8, 143.8, 142.9, 142.4, 140.5, 136.7, 133.5, 129.5 (2C),
127.8 (2C), 125.7, 122.7, 121.1, 119.9, 115.8, 59.5, 37.9, 21.5
(2C), 17.3; MS (EI, 70 eV): m/e (%)=353.1 ([M]+, 100),
198.1 (40), 157.1 (100), 142.1 (35); HR-MS (EI, 70 eV): m/
e=353.1444, calcd. for C21H23NO2S [M]+: 353.1450.
N-Methyl-4-phenylnaphthalen-2-amine (2n): yield: 19 mg
(0.08 mmol, 54%); yellow oil; IR (CH2Cl2): n=3418, 3056,
2897, 1714, 1621, 1500, 1409, 1233, 703 cmÀ1 1H NMR
;
(400 MHz, CDCl3): d=7.68 (t, J=7.9 Hz, 2H), 7.50–7.45
(m, 4H), 7.45–7.39 (m, 1H), 7.39–7.34 (m, 1H), 7.17–7.10
(m, 1H), 6.83 (s, 2H), 3.90 (s, 1H), 2.97 (s, 3H); 13C NMR
(100 MHz, CDCl3): d=146.3, 141.2, 140.7, 135.8, 129.9 (2C),
128.1 (2C), 127.2, 126.3, 126.2, 125.9, 125.9, 122.0, 118.8,
N-[5,6-Dimethoxy-1-(prop-1-en-2-yl)-1H-inden-2-yl]-N,4-
dimethylbenzenesulfonamide (4c): yield: 90 mg (0.23 mmol,
90%); white solid; mp 132–1338C; IR (CH2Cl2): n=3344,
Adv. Synth. Catal. 2015, 357, 3242 – 3254
ꢀ 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
3249

FULL PAPERS
Ming-Chang P. Yeh et al.
3079, 2938, 2254, 1921, 1644, 1597, 1491, 1354, 1299, 1167,
1105 cmÀ1 1H NMR (400 MHz, CDCl3): d=7.60 (d, J=
(m, 1H), 6.55 (s, 1H), 5.16–5.12 (m, 2H), 4.98 (s, 1H), 4.48–
4.44 (m, 2H), 2.37 (s, 3H), 0.66 (s, 3H); 13C NMR
(100 MHz, CDCl3): d=146.3, 143.8, 142.8, 142.5, 142.3,
136.3, 135.4, 129.4 (2C), 128.3 (2C), 128.0 (2C), 127.7 (2C),
127.5, 126.8, 124.8, 122.8, 122.0, 120.4, 116.4, 292, 52.8, 21.4,
16.6; MS (APCI): m/e (%)=416.2 ([M+H]+, 100); HR-MS
(APCI): m/e=416.1679, calcd. for C26H26NO2S [M+H]+:
416.1684.
;
8.2 Hz, 2H), 7.27 (d, J=8.1 Hz, 2H), 6.86 (s, 1H), 6.78 (s,
1H), 6.14 (s, 1H), 5.25 (s, 1H), 5.09 (s, 1H), 4.68 (s, 1H),
3.89 (s, 3H), 3.87 (s, 3H), 3.07 (s, 3H), 2.41 (s, 3H), 1.21 (s,
3H); 13C NMR (100 MHz, CDCl3): d=148.5, 148.3, 147.5,
143.7, 142.9, 135.8 134.5, 133.2, 129.4 (2C), 127.7 (2C),
120.4, 116.1, 107.2, 104.2, 59.9, 56.2, 56.0, 38.0, 21.5, 17.0;
MS (EI, 70 eV): m/e (%)=399.2 ([M]+, 40), 325.2 (20),
244.2 (100), 203.1 (100), 188.1 (15); HR-MS (EI, 70 eV):
m/e=399.1506, calcd. for C22H25NO4S [M]+: 399.1504.
N-Butyl-4-methyl-N-[1-(prop-1-en-2-yl)-1H-inden-2-yl]-
benzenesulfonamide (4h): yield: 91 mg (0.24 mmol, 95%);
yellow oil; IR (CH2Cl2): n=3459, 3069, 2959, 2932, 2340,
1918, 1722, 1642, 1597, 1463, 1353, 1166, 1018, 771 cmÀ1
;
N,4-Dimethyl-N-(5-(prop-1-en-2-yl)-5-indeno[5,6-d][1,3]-
1H NMR (400 MHz, CDCl3): d=7.64 (d, J=8.3 Hz, 2H),
7.24–7.20 (m, 6H), 7.17–7.11 (m, 1H), 6.42 (s, 1H), 5.18 (s,
1H), 5.04 (s, 1H), 4.63 (s, 1H), 3.81–3.74 (m, 1H), 3.32–3.25
(m, 1H), 2.38 (s, 3H), 1.63–1.53 (m, 2H), 1.41–1.26 (m, 2H),
1.10 (s, 2H), 0.89 (t, J=7.3 Hz, 3H); 13C NMR (100 MHz,
CDCl3): d=146.9, 143.5, 143.1, 142.4, 135.4, 129.3 (2C),
127.7 (2C), 127.0, 124.9, 123.0, 121.8, 120.4, 116.4, 77.2, 59.3,
49.5, 30.5, 21.5, 19.9, 17.3, 13.6; MS (APCI): m/e (%)=382.2
([M+H]+, 100); HR-MS (APCI): m/e=382.1838, calcd. for
C23H28NO2S [M+H]+: 382.1841.
dioxol-6-yl)benzenesulfonamide
(0.24 mmol, 95%); yellow oil; IR (CH2Cl2): n=3556, 3370,
2974, 2917, 2204, 1500, 1470, 1355, 1165, 1039, 812 cmÀ1
(4d):
yield:
91 mg
;
1H NMR (400 MHz, CDCl3): d=7.59 (d, J=8.2 Hz, 2H),
7.27 (d, J=6.7 Hz, 2H), 6.80 (s, 1H), 6.69 (s, 1H), 6.10 (s,
1H), 5.25 (s, 1H), 5.92 (d, J=1.5 Hz, 1H), 5.22 (s, 1H), 5.07
(s, 1H), 4.64 (s, 1H), 3.06 (s, 3H), 2.41 (s, 3H), 1.21 (s, 3H);
13C NMR (100 MHz, CDCl3): d=148.4, 146.8, 145.8, 143,7,
142.6, 137.2, 135.6, 133.2, 129.4 (2C), 127.7 (2C), 120.3,
116.2, 104.8, 101.6, 100.8, 59.7, 38.0, 21.5, 16.9; MS (EI,
70 eV): m/e (%)=383.1 ([M]+, 57), 228.1 (98), 187.1 (100),
157.1 (40), 129.1(80), 128.1 (65); HR-MS (EI, 70 eV): m/e=
383.1188, calcd. for C21H21NO4S [M]+: 383.1191.
N,4-Dimethyl-N-(6-(prop-1-en-2-yl)-6H-cyclopenta[b]-
thiophen-5-yl)benzenesulfonamide
(4i):
yield:
86 mg
(0.25 mmol, 99%); white solid; mp 89–908C; IR (CH2Cl2):
n=3907, 3427, 2926, 2357, 2012, 1698, 1453, 1346, 1164,
N-[6-Fluoro-1-(prop-1-en-2-yl)-1H-inden-2-yl]-N,4-dime-
thylbenzenesulfonamide (4e): yield: 83 mg (0.23 mmol,
93%); yellow oil; IR (CH2Cl2): n=3456, 3080, 2973, 2944,
1089 cmÀ1 1H NMR (400 MHz, CDCl3): d=7.60 (d, J=
;
8.3 Hz, 2H), 7.28 (d, J=8.4 Hz, 2H), 7.26 (s, 1H), 6.89 (d,
J=4.8 Hz, 1H), 6.14 (d, J=1.2 Hz, 1H), 5.19 (s, 1H), 5.06
(t, J=1.5 Hz, 1H), 4.78 (s, 1H), 3.04 (s, 3H), 2.42 (s, 3H),
1.35 (s, 3H); 13C NMR (100 MHz, CDCl3): d=150.4, 145.3,
143.7, 142.6, 142.2, 133.0, 129.4 (2C), 127.9 (2C), 127.3,
119.4, 118.5, 115.9, 57.9, 38.5, 21.5, 17.6; MS (EI, 70 eV):
m/e (%)=345.1 ([M]+, 30), 325.2 (50), 279.2 (20), 239.2 (24),
190.1 (100), 149.1 (42), 134.1 (20); HR-MS (EI, 70 eV):
m/e=345.0851, calcd. for C18H19NO2S2 [M]+: 345.0857.
2360, 1919, 1724, 1598, 1475, 1354, 1189, 1034, 864 cmÀ1
;
1H NMR (400 MHz, CDCl3): d=7.63 (d, J=8.3 Hz, 2H),
7.30 (d, J=8.1 Hz, 2H), 7.13 (dd, J=8.2, 5.0 Hz, 1H), 7.03
(dd, J=8.6, 2.3 Hz, 1H), 6.94 (td, J=9.6, 2.5 Hz, 1H), 6.20
(s, 1H), 5.27 (s, 1H), 5.13 (t, J=1.4 Hz, 1H), 4.76 (s, 1H),
3.11 (s, 3H), 2.44 (s, 3H), 1.25 (s, 3H); 13C NMR (100 MHz,
CDCl3): d=161.5 (d, J=240 Hz), 149.3 (d, J=4 Hz), 145.4
(d, J=8 Hz), 143.9, 142.1, 137.9, 133.3, 129.5 (2C), 127.7
(2C), 121,0 (d, J=8 Hz),119.3, 116.6, 113.8 (d, J=23 Hz),
110.9 (d, J=24 Hz), 59.9 (d, J=2 Hz), 37.9, 21.5, 17.2;
19F NMR (376 MHz, CDCl3): d=À118.4; MS (APCI):
m/e (%)=358.1 ([M+H]+, 100), 319.2 (10), 279.2 (10), 229.1
(5), 203.1 (5); HR-MS (APCI): m/e=358.1272, calcd. for
C20H21FNO2S [M+H]+: 358.1277.
tert-Butyl phenyl[1-(prop-1-en-2-yl)-1H-inden-2-yl]carba-
mate (4j): yield: 44 mg (0.13 mmol, 51%); brown oil; IR
(CH2Cl2): n=2977, 1718, 1594, 1459, 1317, 1157, 751 cmÀ1
;
1H NMR (400 MHz, CDCl3): d=7.40–7.31 (m, 2H), 7.31–
7.24 (m, 1H), 7.24–7.20 (m, 2H), 7.20–7.13 (m, 3H), 7.07
(td, J=7.2, 1.6 Hz, 1H), 6.28 (s, 1H), 5.00–4.95 (m, 1H),
4.89 (s, 1H), 4.56 (s, 1H), 1.44 (s, 9H), 1.37 (s, 3H);
13C NMR (100 MHz,CDCl3): d=153.2, 149.8, 143.2, 142.6,
142.5, 142.1, 128.7 (2C), 128.1 (2C), 126.9 (2C), 124.2, 122.8,
120.2, 120.0, 115.6, 81.4, 57.9, 28.1, 17.7; MS (ESI): m/
e (%)=370.0 ([M+Na]+, 100), 347.8 (10), 292.1 (43), 180.7
(7); HR-MS (ESI): m/e=370.1783, calcd. for C23H25NO2Na
[M+Na]+: 370.1783.
N-[6-Chloro-1-(prop-1-en-2-yl)-1H-inden-2-yl]-N,4-dime-
thylbenzenesulfonamide (4f): yield: 93 mg (0.25 mmol,
99%); yellow oil; IR (CH2Cl2): n=2973, 2942, 2362, 1597,
1587, 1358, 1169, 866, 814 cmÀ1
;
1H NMR (400 MHz,
CDCl3): d=7.60 (d, J=8.2 Hz, 2H), 7.28 (s, 1H), 7.26– 7.25
(m, 2H), 7.19 (dd, J=8.0, 1.9 Hz, 2H), 7.09 (d, J=8.0 Hz,
2H), 6.19 (s, 1H), 5.24 (s, 1H), 5.10 (s, 1H), 4.73 (s, 1H),
3.10 (s, 3H), 2.41 (s, 3H), 1.22 (s, 3H); 13C NMR (100 MHz,
CDCl3): d=150.0, 144.9, 144.0, 141.9, 140.7, 130.8, 129.5
(2C), 127.7 (2C), 127.2. 123.5, 121.1, 120.5, 118.8, 116.7,
59.8, 37.8, 21.5, 17.2; MS (ESI): m/e (%)=376.0 ([M+2+
H]+, 374.0 ([M+H]+, 100), 219.1 (30); HR-MS (ESI): m/e=
374.0980, calcd. for C20H21NO2SCl [M+H]+: 374.0982.
Typical Procedure for the Preparation of N,4-
Dimethyl-N-[1-(tribromomethyl)-1H-inden-2-
yl]benzenesulfonamide (9a) in Dichloromethane
To a solution of N-{[2-(2,2-dibromovinyl)phenyl]ethynyl}-
N,4-dimethylbenzenesulfonamide (8a, 94 mg, 0.2 mmol) in
dichloromethane (2.0 mL) was added InBr3 (85 mg,
0.24 mmol) at room temperature under an atmosphere of ni-
trogen. The reaction mixture was stirred until no trace of 8a
was detected on TLC (ca. 10 min), and then concentrated
under reduced pressure to give a crude liquid. The resulting
crude mixture was purified by flash column chromatography
N-Benzyl-4-methyl-N-[1-(prop-1-en-2-yl)-1H-inden-2-yl]-
benzenesulfonamide (4g): yield: 98 mg (0.24 mmol, 94%);
white solid; mp 128–1298C; IR (CH2Cl2): n=3429, 3066,
2971, 2340, 1643, 1596, 1566, 1456, 1352, 1164, 1090,
699 cmÀ1
;
1H NMR (400 MHz, CDCl3): d=7.69 (d, J=
8.2 Hz, 2H), 7.33 (d, J=7.2 Hz, 2H), 7.24 (d, J=8.2 Hz,
2H), 7.23 (d, J=7.4 Hz, 2H), 7.19–7.10 (m, 4H), 7.07–7.03
3250
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FULL PAPERS
Indium(III)-Catalyzed Cyclization of Aromatic 5-Enynamides
[silica gel, 20% EtOAc in hexanes] to afford product 9a as
a green solid; yield: 66 mg (0.12 mmol, 60%).
The product 9b was prepared by a similar method.
6.65 (m, 2H), 5.04 (s, 2H), 2.34 (s, 3H); 13C NMR
(100 MHz, CDCl3): d=144.2, 143.0, 139.5, 137.3, 136.7,
135.9, 132.0, 131.7, 130.5 (2C), 129.9 (3C), 129.7, 128.8,
127.8 (2C), 127.2 (2C), 125.0, 124.6, 121.7, 119.3, 118.7, 55.5,
21.5; MS (EI, 70 eV): m/e (%)=570.9 ([M+4]+, 27), 569.0
([M+2]+, 59), 567.0 ([M]+, 24), 412.0 (58), 334.1 (34), 254.2
N,4-Dimethyl-N-[1-(tribromomethyl)-1H-inden-2-yl]ben-
zenesulfonamide (9a): yield: 66 mg 0.12 mmol, 60%); green
solid; mp 181–1828C; IR (CH2Cl2): n=3067, 2914, 2361,
1920, 1701, 1598, 1464, 1352, 1168, 1088, 1031, 906 cmÀ1
;
(93);
C26H19Br2NO2S [M]+: 566.9503.
(E)-4-Bromo-3-[bromo(phenyl)methylene]-6-fluoro-1-
HR-MS
(ESI):
m/e=566.9509,
calcd.
for
1H NMR (400 MHz, CDCl3): d=8.18 (d, J=7.5 Hz, 1H),
7.57 (d, J=8.1 Hz, 2H), 7.38 (td, J=7.3, 0.7 Hz, 1H), 7.32–
7.34 (m, 3H), 7.24 (d, J=7.4 Hz, 1H), 6.29 (s, 1H),5.30 (m,
1H), 3.11 (s, 3H), 2.44 (s, 3H); 13C NMR (100 MHz,
CDCl3): d=147.4, 147.9, 141.6, 140.7, 132.1, 129.4 (2C),
129.3, 128.9, 128.1 (2C), 126.9, 125.8, 121.4, 69.2, 39.6, 28.8,
21.5; MS (APCI): m/e (%)=553.8 ([M+6+H]+, 10), 551.8
([M+4+H]+, 30), 549.9 ([M+2+H]+, 30), 547.9 ([M+H]+,
10), 265.1 (15), 233.1 (100), 216.1 (20); HR-MS (APCI):
m/e=547.8538, calcd. for C18H17NO2SBr3 [M+H]+:
547.8530.
tosyl-2,3-dihydro-1H-indeno[2,1-b]pyridine (12b): Yield:
65 mg (0.12 mmol, 60%); red solid; mp 156–1578C; IR
(CH2Cl2): n=2918, 2848, 1581, 1463, 1362, 1274, 1167, 1088,
954 cmÀ1
;
1H NMR (400 MHz, CDCl3): d=7.79 (d, J=
8.3 Hz, 2H), 7.76 (dd, J=9.9, 2.4 Hz, 1H), 7.32 (td, J=6.8,
1.2 Hz, 1H), 7.21 (d, J=8.2 Hz, 2H), 7.20 (d, J=8.0 Hz,
2H), 7.09 (dd, J=8.2, 5.2 Hz, 1H), 6.92 (ddd, J=8.9, 8.2,
2.4 Hz, 1H), 6.81 (s, 1H), 6.67 (d, J=7.1 Hz, 2H), 5.03 (s,
2H), 2.30 (s, 3H); 13C NMR (100 MHz, CDCl3): d=161.0
(d, J=243 Hz),144.2, 139.4, 138.6, 135.7, 133.6 (d, J=
9 Hz),132.6, 130.4 (2C), 130.0, 129.9 (2C), 128.5, 127.8 (2C),
127.1 (2C), 122.0 (d, J=8 Hz), 119.9, 118.8, 115.5 (d, J=
22 Hz),112.9 (d, J=26 Hz), 55.4, 21.4; 19F NMR (376 MHz,
CDCl3): d=À117.0; MS (EI, 70 eV): m/e (%)=589.0 ([M+
4]+, 22), 587.0 ([M+2]+, 44), 585.0 ([M]+, 22), 458.0 (10),
431.9 (100), 352 (30), 351 (30), 272.1 (60), 271.1 (40), 244.1
(25); HR-MS (EI, 70 eV): m/e=584.9407, calcd. for
C26H18FNO2SBr2 [M]+: 584.9407.
N-[6-Fluoro-1-(tribromomethyl)-1H-inden-2-yl]-N,4-dime-
thylbenzenesulfonamide (9b): yield: 63 mg (0.11 mmol,
55%); green solid; mp 243–2448C; IR (CH2Cl2): n=3072,
2940, 2358, 1598, 1473, 1460, 1351, 1163, 1087, 1026,
1
906 cmÀ1; H NMR (400 MHz, CDCl3): d=7.94 (dd, J=9.6,
2.2 Hz, 1H), 7.56 (d, J=8.7 Hz, 2H), 7.30 (d, J=8.1 Hz,
2H), 7.17 (dd, J=8.2, 5.2 Hz, 1H), 7.08 (td, J=8.7, 2.4 Hz,
1H), 6.25 (s, 1H), 5.28 (s, 1H), 3.09 (s, 3H), 2.44 (s, 3H);
13C NMR (100 MHz, CDCl3): d=161.2 (d, J=245 Hz),
147.1, 144.0, 142.7 (d, J=9 Hz),137.4, 132.2, 129.4 (2C),
128.5, 128.1 (2C), 122.0 (d, J=8 Hz), 115.7 (d, J=23 Hz),
115.4 (d, J=26 Hz), 69.2, 38.8, 38.3, 21.5; 19F NMR
(376 MHz, CDCl3): d=À114.8; MS (FAB): m/e (%)=570.8
([M+6]+, 10), 568.8 ([M+4]+, 30), 566.8 ([M+2]+, 30),
564.8 ([M]+, 10), 487.9 (25), 460.1 (5), 391.3 (5), 307.1 (35),
289.1 (20), 235.2 (10), 219.2 (5); HR-MS (FAB): m/e=
564.8353, calcd. for C18H15NO2SBr3F [M]+: 564.8358.
(E)-Ethyl 4-{bromo(4-bromo-1-tosyl-1H-indeno[2,1-b]pyr-
idin-3(2H)-ylidene)methyl}benzoate (12c): yield: 90 mg
(0.14 mmol, 71%); red solid; mp 163–1658C; IR (CH2Cl2):
1
n=3055, 2985, 1717, 1601, 1352, 1274, 1166 cmÀ1; H NMR
(400 MHz, CDCl3): d=7.97 (d, J=7.6 Hz, 1H), 7.86 (d, J=
8.4 Hz, 2H), 7.80 (d, J=8.2 Hz, 2H), 7.25–7.15 (m, 4H),
7.03 (td, J=7.5, 1.0 Hz, 1H), 6.85 (s, 1H), 6.76 (d, J=
8.2 Hz, 2H), 5.03 (s, 2H), 4.38 (q, J=7.1 Hz, 2H), 2.36 (s,
3H), 1.40 (t, J=7.1 Hz, 3H); 13C NMR (100 MHz, CDCl3):
d=165.7, 144.3, 143.7, 142.9, 137.9, 136.6, 135.8, 131.9, 131.5,
130.3 (2C), 130.1, 129.9 (3C), 129.7, 128.9 (2C), 127.2 (2C),
125.2, 124.7, 121.8, 119.8, 117.7, 61.3, 55.3, 21.5, 14.2; MS
(FAB): m/e (%)=643.0 ([M + 4]+, 67), 640.9 ([M + 2]+,
100), 638.9 ([M+], 45), 485.9 (44), 406.0 (9); HR-MS (FAB):
m/e=638.9702, calcd. for C29H23Br2NO4S [M]+: 638.9715.
(E)-Ethyl 3-{bromo(4-bromo-1-tosyl-1H-indeno[2,1-b]pyr-
idin-3(2H)-ylidene)methyl}benzoate (12d): yield: 90 mg
(0.15 mmol, 74%); red solid; mp 148–1508C; IR (CH2Cl2):
Typical Procedure for the Preparation of (E)-4-
Bromo-3-[bromo(phenyl)methylene]-1-tosyl-2,3-
dihydro-1H-indeno[2,1-b]pyridine (12a) in 1,2-
Dichloroethane
To a solution of N-{[2-(2,2-dibromovinyl)phenyl]ethynyl}-N-
(3-phenylprop-2-yn-1-yl)tolylsulfonamide (11a, 0.11 mg,
0.20 mmol) in 1,2-dichloroethane (20 mL) was added InBr3
(35 mg, 0.10 mmol) at 808C under an atmosphere of nitro-
gen. The reaction mixture was stirred until no trace of 11a
was detected on TLC in 10 min. The mixture was filtered
through a bed of Celiteꢁ and concentrated to give a crude
solid. The resulting crude mixture was purified by flash
column chromatography [silica gel, 5% EtOAc in hexanes]
n=3066, 2979, 1717, 1601, 1447, 1351, 1240, 1166 cmÀ1
;
1H NMR (400 MHz, CDCl3): d=7.98 (d, J=7.7 Hz, 2H),
7.81 (d, J=8.3 Hz, 2H), 7.61 (s, 1H), 7.25–7.15 (m, 5H),
7.03 (td, J=7.6, 1.2 Hz, 1H), 6.84 (s, 1H), 6.70 (d, J=
7.8 Hz, 1H), 5.11 (br s, 1H), 4.95 (br s, 1H), 4.37 (q, J=
7.1 Hz, 2H), 2.31 (s, 3H), 1.38 (t, J=7.2 Hz, 3H); 13C NMR
(100 MHz, CDCl3): d=165.6, 144.4, 143.0, 139.8, 137.8,
136.5, 135.9, 134.4, 132.0, 131.3, 130.7, 130.5, 129.9 (3C),
129.8, 129.7, 127.7, 127.2 (2C), 125.1, 124.7, 121.7, 119.6,
117.8, 61.3, 55.4, 21.4, 14.3; MS (ESI): m/e (%)=666.0
([M+4+Na]+, 35), 664.0 ([M+2+Na]+, 100), 662.0 ([M+
Na]+, 33), 397.4 (8), 274.3 (32), 264.1 (7); HR-MS (ESI):
m/e=661.9617, calcd. for C29H23Br2NO4S [M+Na]+:
661.9612.
to afford product 12a as
a red solid; yield: 88 mg
(0.16 mmol, 78%).
The products 12b–i (from 0.20 mmol of 11b–i and 0.10
mml of InBr3) and 17a–f (from 0.15 mmol of 16a–f and
0.075 mmol of InCl3) were prepared by a similar method.
(E)-4-Bromo-3-[bromo(phenyl)methylene]-1-tosyl-2,3-di-
hydro-1H-indeno[2,1-b]pyridine
(12a):
yield:
88 mg
(0.16 mmol, 78%); red solid; mp 173–1748C; IR (CH2Cl2):
1
n=3059, 2914, 2355, 1601, 1447, 1352, 1166 cmÀ1; H NMR
(E)-4-Bromo-3-[bromo(4-bromophenyl)methylene]-1-
tosyl-2,3-dihydro-1H-indeno[2,1-b]pyridine (12e): yield:
121 mg (0.19 mmol, 93%); red solid; mp 162–1638C; IR
(400 MHz, CDCl3): d=8.01 (d, J=7.4 Hz, 1H), 7.81 (d, J=
8.3 Hz, 2H), 7.31 (ddd, J=8.0, 6.9, 1.2 Hz, 1H), 7.24–7.16
(m, 6H), 7.03 (td, J=7.6, 1.4 Hz, 1H), 6.85 (s, 1H), 6.72–
Adv. Synth. Catal. 2015, 357, 3242 – 3254
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FULL PAPERS
Ming-Chang P. Yeh et al.
(CH2Cl2): n=3063, 2920, 1913, 1600, 1447, 1352, 1167 cmÀ1
;
7.03 (td, J=7.5, 1.4 Hz, 1H), 6.83 (s, 1H), 6.69 (d, J=
9.0 Hz, 2H), 6.61 (d, J=8.8 Hz, 2H), 5.01 (s, 2H), 3.80 (s,
3H), 2.32 (s, 3H); 13C NMR (100 MHz, CDCl3): d=161.1,
144.1, 143.0, 136.9, 136.7, 136.0, 132.3 (2C), 132.1, 131.7,
129.9 (3C), 129.6, 127.6, 127.2 (2C), 125.0, 124.5, 121.6,
119.3, 119.1, 113.1 (2C), 55.7, 55.4, 21.5; MS (FAB): m/
e (%)=601.0 ([M+4]+, 63), 598.9 ([M+2]+, 100), 596.9
([M]+, 46), 443.9 (52), 364.0 (30); HR-MS (FAB): m/e=
596.9611, calcd. for C27H21Br2NO3S [M]+: 596.9609.
1H NMR (400 MHz, CDCl3): d=8.00 (d, J=7.6 Hz, 1H),
7.79 (d, J=8.3 Hz, 2H), 7.33 (d, J=8.6 Hz, 2H), 7.25–7.13
(m, 4H), 7.05 (td, J=7.6, 1.3 Hz, 1H), 6.85 (s, 1H), 6.55 (d,
J=8.5 Hz, 2H), 5.01 (s, 2H), 2.35 (s, 3H); 13C NMR
(100 MHz, CDCl3): d=144.2, 143.0, 138.4, 137.7, 136.7,
135.8, 131.9, 131.9 (2C), 131.0 (2C), 129.9 (3C), 129.9, 129.5,
127.2 (2C), 125.2, 124.6, 124.4, 121.8, 119.7, 118.0, 55.4, 21.5;
MS (FAB): m/e (%)=648.8 ([M+4]+, 100), 646.9 ([M+2]+,
89), 644.8 ([M]+, 31), 493.8 (53), 413.9 (19), 334.0 (18); HR-
MS (FAB): m/e=644.8622, calcd. for C26H18Br3NO2S [M]+:
644.8608.
(E)-4-Chloro-3-[chloro(phenyl)methylene]-1-tosyl-2,3-di-
hydro-1H-indeno[2,1-b]pyridine
(17a):
yield:
45 mg
(0.10 mmol, 63%); red solid; mp 145–1468C; IR (CH2Cl2):
1
(E)-4-Bromo-3-[bromo(4-chlorophenyl)methylene]-1-
tosyl-2,3-dihydro-1H-indeno[2,1-b]pyridine (12f): yield:
75 mg (0.13 mmol, 62%); red solid; mp 166–1678C; IR
n=3062, 2926, 2359, 1598, 1491, 1355, 1167 cmÀ1; H NMR
(400 MHz, CDCl3): d=7.78 (d, J=7.7 Hz, 1H), 7.76 (d, J=
8.3 Hz, 2H), 7.38–7.30 (m, 1H), 7.24–7.16 (m, 6H), 7.09–
6.99 (m, 1H), 6.84 (s, 1H), 6.74 (d, J=7.5 Hz, 2H), 4.99 (s,
2H), 2.34 (s, 3H); 13C NMR (100 MHz, CDCl3): d=144.2,
142.7, 138.0, 137.8, 136.6, 135.4, 134.4, 131.2, 130.0 (3C),
129.8 (2C), 129.5, 128.9, 127.8 (2C), 127.1 (2C), 125.3, 125.1,
124.9, 121.6, 119.5, 52.0, 21.5; MS (ESI): m/e (%)=504.0
([M+2+Na]+, 38), 502.0 ([M+Na]+, 52), 439.5 (8), 397.4
(7), 337.1 (9), 321.0 (11); HR-MS (ESI): m/e=502.0421,
calcd. for C26H19Cl2NO2NaS [M+Na]+: 502.0411.
(CH2Cl2): n=3053, 2919, 1600, 1449, 1352, 1166 cmÀ1
;
1H NMR (400 MHz, CDCl3): d=8.00 (d, J=7.6 Hz, 1H),
7.79 (d, J=8.3 Hz, 2H), 7.27–7.14 (m, 6H), 7.04 (td, J=7.6,
1.2 Hz, 1H), 6.85 (s, 1H), 6.61 (d, J=8.5 Hz, 2H), 5.01 (s,
2H), 2.35 (s, 3H); 13C NMR (100 MHz, CDCl3): d=144.2,
142.9, 138.0, 137.7, 136.6, 136.1, 135.8, 131.9, 131.7 (2C),
129.9 (2C), 129.9 (2C), 129.5, 128.1 (2C), 127.2 (2C), 125.2,
124.6, 121.8, 119.7, 118.0, 55.4, 21.5; MS (ESI): m/e (%)=
604.9 ([M+4]+, 40), 602.8 ([M+2]+, 50), 600.8 ([M]+, 21),
447.9 (23), 368.0 (8); HR-MS (ESI): m/e=600.9119, calcd.
for C26H18Br2ClNO2S [M]+: 600.9114.
(E)-4-Chloro-3-[chloro(p-tolyl)methylene]-1-tosyl-2,3-di-
hydro-1H-indeno[2,1-b]pyridine
(0.08 mmol, 51%); red solid; mp 175–1778C; IR (CH2Cl2):
n=3059, 2927, 1597, 1447, 1353, 1169 cmÀ1 1HNMR
(17b):
yield:
38 mg
(E)-4-Bromo-3-[bromo(p-tolyl)methylene]-1-tosyl-2,3-di-
;
hydro-1H-indeno[2,1-b]pyridine
(0.13 mmol, 64%); red solid; mp 188–1898C; IR (CH2Cl2):
n=3034, 2922, 1909, 1600, 1572, 1447, 1352, 1165 cmÀ1
(12g):
yield:
74 mg
(400 MHz, CDCl3): d=7.79 (d, J=7.6 Hz, 1H), 7.75 (d, J=
8.3 Hz, 2H), 7.23–7.15 (m, 4H), 7.05–6.98 (m, 3H), 6.83 (s,
1H), 6.64 (d, J=8.1 Hz, 2H), 4.98 (s, 2H), 2.36 (s, 3H), 2.34
(s, 3H); 13C NMR (100 MHz, CDCl3): d=144.1, 142.7, 140.4,
138.4, 136.6, 135.4, 135.0, 134.2, 131.2, 129.9 (2C), 129.8
(2C), 129.4, 129.2, 128.5 (2C), 127.1 (2C), 125.2, 124.8,
124.5, 121.6, 119.3, 52.0, 21.5, 21.4; MS (ESI): m/e (%)=
518.1 ([M+2+Na]+, 12), 516.1 ([M+Na]+, 17), 437.4 (5),
381.4 (3), 360.3 (11), 304.3 (12); HR-MS (ESI): m/e=
516.0555, calcd. for C27H21Cl2NO2NaS [M+Na]+: 516.0568.
(E)-4-Chloro-3-[chloro(m-tolyl)methylene]-1-tosyl-2,3-di-
;
1H NMR (400 MHz, CDCl3): d=8.02 (d, J=7.6 Hz, 1H),
7.79 (d, J=8.3 Hz, 2H), 7.25–7.16 (m, 4H), 7.03 (td, J=7.5,
1.4 Hz, 1H), 6.84 (s, 1H), 6.58 (d, J=8.1 Hz, 2H), 5.02 (s,
2H), 2.34 (s, 3H), 2.34 (s, 3H); 13C NMR (100 MHz,
CDCl3): d=144.1, 143.0, 140.4, 137.1, 136.7, 136.7, 136.0,
132.2, 132.1, 130.5 (2C), 129.9 (2C), 129.6, 128.5 (2C), 128.2,
127.2 (2C), 125.0, 124.5, 121.6, 119.1, 119.1, 55.6, 21.4; MS
(ESI): m/e (%)=586.0 ([M+4+H]+, 30), 584.0 ([M+2+
H]+, 73), 582.0 ([M+H]+, 27), 504.0 (7), 419.3 (3), 348.0 (7),
311.1 (21); HR-MS (ESI): m/e=581.9739, calcd. for
C27H22Br2NO2S [M+H]+: 581.9738.
hydro-1H-indeno[2,1-b]pyridine
(0.08 mmol, 52%); red solid; mp 119–1208C; IR (CH2Cl2):
n=3059, 2920, 1598, 1447, 1354, 1166 cmÀ1 1H NMR
(17c):
yield:
39 mg
;
(E)-4-Bromo-3-[bromo(m-tolyl)methylene]-1-tosyl-2,3-di-
hydro-1H-indeno[2,1-b]pyridine (12h): 58 mg (0.10 mmol,
50%); red solid; mp 188–1898C; IR (CH2Cl2): n=3055,
(400 MHz, CDCl3): d=7.79 (d, J=7.7 Hz, 1H), 7.76 (d, J=
8.3 Hz, 2H), 7.22–7.17 (m, 4H), 7.15 (d, J=7.7 Hz, 1H),
7.09 (t, J=7.6 Hz, 1H), 7.06–7.00 (m, 1H), 6.83 (s, 1H), 6.62
(s, 1H) 6.51 (d, J=7.6 Hz, 1H), 4.98 (s, 2H), 2.34 (s, 3H),
2.28 (s, 3H); 13C NMR (100 MHz, CDCl3): d=144.1, 142.7,
138.3, 137.8, 137.5, 136.6, 135.4, 134.3, 131.2, 130.7, 130.1,
129.9 (2C), 129.4, 129.1, 127.6, 127.1 (2C), 127.0, 125.2,
124.9, 124.8, 121.6, 119.3, 51.9, 21.5, 21.2; MS (EI, 70 eV):
m/e (%)=495.2 ([M+2]+, 7), 493.2 ([M+], 4), 394.2 (18),
358.2 (3), 303.1 (6), 267.2 (19); HR-MS (EI, 70 eV): m/e=
493.0676, calcd. for C27H21Cl2NO2S [M]+: 493.0670.
1
2919, 1600, 1574, 1449, 1352, 1166 cmÀ1; H NMR (400 MHz,
CDCl3): d=8.02 (d, J=7.7 Hz, 1H), 7.81 (d, J=8.3 Hz, 2H),
7.25–7.16 (m, 4H), 7.12 (d, J=7.6 Hz, 1H), 7.09–7.00 (m,
2H), 6.84 (s, 1H), 6.57 (s, 1/H), 6.45 (d, J=7.5 Hz, 1H),
5.03 (s, 2H), 2.34 (s, 3H), 2.26 (s, 3H); 13C NMR (100 MHz,
CDCl3): d=144.1, 143.0, 139.5, 137.5, 137.2, 136.7, 136.0,
132.1, 132.1, 130.9, 130.7, 129.9 (2C), 129.6, 128.6, 127.7,
127.6, 127.3 (2C), 125.0, 124.6, 121.6, 119.1, 119.0, 55.5, 21.5,
21.2; MS (ESI): m/e (%)=608.0 ([M+4+Na]+, 45), 606.0
([M+2+Na]+, 100), 604.0 ([M+Na]+, 40), 507.0 (12), 471.4
(18), 409.0 (26), 317.0 (30); HR-MS (ESI): m/e=603.9563,
calcd. for C27H21Br2NO2NaS [M+Na]+: 603.9557.
(E)-4-Chloro-3-[chloro(p-tolyl)methylene]-1-tosyl-2,3-di-
hydro-1H-indeno[2,1-b]pyridine
(17d):
yield:
39 mg
0.08 mmol, 50%); red solid; mp 166–1678C; IR (CH2Cl2):
1
n=3061, 2931, 1600, 1450, 1354, 1255, 1168 cmÀ1; H NMR
(E)-4-Bromo-3-[bromo(4-methoxyphenyl)methylene]-1-
(400 MHz, CDCl3): d=7.80 (d, J=7.6 Hz, 1H), 7.74 (d, J=
8.3 Hz, 2H), 7.23–7.12 (m, 4H), 7.07–7.00 (m, 1H), 6.82 (s,
1H), 6.77–6.64 (m, 4H), 4.97 (s, 2H), 3.82 (s, 3H), 2.33 (s,
3H); 13C NMR (100 MHz, CDCl3): d=161.1, 144.1, 142.7,
138.2, 136.6, 135.4, 134.0, 131.6 (2C), 131.2, 130.0, 129.9
(2C), 129.3 (2C), 127.1 (2C), 125.2, 124.8, 123.8, 121.6,
tosyl-2,3-dihydro-1H-indeno[2,1-b]pyridine
(12i):
yield:
55 mg (0.09 mmol, 46%); red solid; mp 175–1768C; IR
(CH2Cl2): n=3047, 2941, 2356, 1601, 157/4, 1448, 1351, 1252,
1166 cmÀ1 1H NMR (400 MHz, CDCl3): d=8.03 (d, J=
;
7.6 Hz, 1H), 7.79 (d, J=8.3 Hz, 2H), 7.25–7.15 (m, 4H),
3252
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FULL PAPERS
Indium(III)-Catalyzed Cyclization of Aromatic 5-Enynamides
119.2, 113.1 (2C), 55.3, 52.2, 21.5; MS (EI, 70 eV):
m/e (%)=511.1 ([M+2]+, 30), 509.2 ([M]+, 35), 464.2 (4),
354.1 (100), 319.1 (25), 308.1 (23), 240.1 (13); HR-MS (EI,
70 eV): m/e=509.0625, calcd. for C27H21Cl2NO3S [M]+:
509.0619.
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(E)-4-Chloro-3-[chloro(4-bromophenyl)methylene]-1-
tosyl-2,3-dihydro-1H-indeno[2,1-b]pyridine (17e): yield:
60 mg (0.11 mmol, 72%); red solid; mp 128–1298C; IR
(CH2Cl2): n=3072, 2921, 1600, 1449, 1353, 1166 cmÀ1
;
1H NMR (400 MHz, CDCl3): d=7.78 (d, J=8.3 Hz, 1H),
7.74 (d, J=8.3 Hz, 2H), 7.35 (d, J=8.6 Hz, 2H), 7.24–7.16
(m, 4H), 7.04 (ddd, J=7.6, 7.0, 1.9 Hz, 1H), 6.84 (s, 1H),
6.61 (d, J=8.5 Hz, 2H), 4.96 (s, 2H), 2.35 (s, 3H); 13C NMR
(100 MHz, CDCl3): d=144.2, 142.7, 136.8, 136.6, 136.4,
135.3, 134.8, 131.3 (2C), 131.1 (3C), 129.9 (2C), 129.7, 128.1,
127.2 (2C), 125.8, 125.4, 125.0, 124.5, 121.7, 119.9, 51.9, 21.5;
MS (EI, 70 eV): m/e (%)=559.1 ([M+2]+, 33), 557.1 ([M]+,
18), 404.0 (100), 368.1 (14), 323.1 (22), 288.1 (21), 246.1
(28); HR-MS (EI, 70 eV): m/e=556.9616, calcd. for
C26H18BrCl2NO2S [M]+: 556.9619.
(E)-Ethyl 4-{chloro(4-chloro-1-tosyl-1H-indeno[2,1-b]pyr-
idin-3(2H)-ylidene)methyl}benzoate (17f): yield: 44 mg
(0.08 mmol, 53%); red solid; mp 156–1578C; IR (CH2Cl2):
1
n=3055, 2919, 2232, 1719, 1596, 1370, 1169 cmÀ1; H NMR
(400 MHz, CDCl3): d=7.89 (d, J=8.6 Hz, 2H), 7.78–7.72
(m, 3H), 7.23–7.18 (m, 4H), 7.03 (ddd, J=7.6, 6.9, 1.9 Hz,
1H), 6.84 (s, 1H), 6.82 (d, J=8.4 Hz, 2H), 4.98 (s, 2H), 4.39
(q, J=7.1 Hz, 2H), 2.37 (s, 3H), 1.40 (t, J=7.1 Hz, 3H);
13C NMR (100 MHz, CDCl3): d=165.7, 144.4, 142.7, 142.1,
136.5, 136.3, 135.2, 134.9, 131.6, 131.0, 130.0 (2C), 129.7,
129.7 (2C), 128.9 (2C), 127.9, 127.1 (2C), 126.3, 125.4, 125.0,
121.7, 120.0, 61.3, 51.8, 21.5, 14.3; MS (EI, 70 eV):
m/e (%)=553.1 ([M+2]+, 13), 551.2 ([M]+, 17), 452.2 (5),
396.1 (100), 368.1 (26), 332.1 (19), 288.1 (47); HR-MS (EI,
70 eV): m/e=551.0723, calcd. for C29H23Cl2NO4S [M]+:
551.0725.
Supporting Information
Spectroscopic characterization and copies of 1H/13C NMR
spectra of compounds 1a–m, 2a–m, 3a–i, 4a–i, 8a, b, 9a, b,
11a–i, 12a–i, 16a–f, and 17a–f and X-ray crystallographic in-
formation files for compounds 2d, 2l, 4b, 4g, 9a, 12a, 17a,
and 17b are available in the Supporting Information.
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Acknowledgements
This work is supported by the Ministry of Science and Tech-
nology (NSC 101-2113M-003-002-MY3) and National
Taiwan Normal University.
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Adv. Synth. Catal. 2015, 357, 3242 – 3254