Chemoselective C-benzylation of unprotected anilines with benzyl alcohols using Re2O7 catalyst

Article abstract of DOI:10.1021/jo4028598

An unprecedented dehydrative C-C bond formation between unprotected anilines with benzyl alcohols is disclosed. Re₂O₇ catalyst (5 mol %) at elevated reaction temperature (80 °C) provided C-benzylanilines with high to excellent yields and with good chemoselectivities (over N-alkylation). A probable mechanism has been proposed based on mechanistic studies.

Full text of DOI:10.1021/jo4028598

Article
pubs.acs.org/joc
Chemoselective C‑Benzylation of Unprotected Anilines with Benzyl
Alcohols Using Re2O7 Catalyst
Rajender Nallagonda,‡ Mohammad Rehan,‡ and Prasanta Ghorai*
Department of Chemistry, Indian Institute of Science Education and Research (IISER) Bhopal, Indore By-pass Road, Bhauri,
Bhopal-462066, India
S
* Supporting Information
ABSTRACT: An unprecedented dehydrative C−C bond formation
between unprotected anilines with benzyl alcohols is disclosed. Re2O7
catalyst (5 mol %) at elevated reaction temperature (80 °C) provided
C-benzylanilines with high to excellent yields and with good
chemoselectivities (over N-alkylation). A probable mechanism has
been proposed based on mechanistic studies.
deactivation of the aromatic ring of aniline toward electrophilic
INTRODUCTION
■
substitution via the coordination of Lewis acid with the amine
Benzyl-substituted anilines represent the recurring precursors
for the synthesis of many complex molecular architectures and
bioactive molecules with pharmaceutical relevance.1 Anilines
containing ortho-chiral alkyl substituents are being used as
chiral building blocks for the preparation of various chiral
ligands.2 The amine functionality of benzylanilines could easily
be converted to various functional groups.3 Despite the versatile
importance of such substituted anilines, their viable synthetic
protocols are extremely rare to date.4,5 The pioneering
synthesis of such C-benzylanilines has been accomplished via
hydroarylation of anilines with styrenes by Beller,4a Acker-
mann,4b Bergman,4c Coates,4d Peris,4e and Li4f (Scheme 1A).
Nevertheless, in many cases the requirement of harsh reaction
conditions and very limited substrate scope has been realized.
Friedel−Crafts (FC) alkylation reactions are among the most
efficient processes for critical C−C bond formation from
unactivated aromatic C−H bonds.6 Despite the tremendous
advancement in such FC benzylation reactions, arenes bearing
unprotected amine (aniline 1) usually provide only the N-
alkylated anilines (4, Scheme 1B).7 This is due to the strong
(aniline)8 or the buffering effect of anilines with Bronsted
̈
acids.9 In recent times, the direct use of benzyl alcohols as
electrophiles instead of corresponding toxic alkyl halides has
been a rapidly developing trend in organic synthesis10 and
eventually has been adopted for FC benzylation as well.11
Therefore, development of a mild catalytic method for the
synthesis of such C-benzylanilines (3) via dehydrative coupling
of unprotected anilines and benzyl alcohols would synthetically
be an attractive strategy for the synthesis of C-benzylanilines.
We envisioned that condensation of alcohol 1 and aniline 2
ultimately would lead to benzylated aniline 3 via the formation
of N-alkylaniline 4, followed by the Hofmann−Martius
rearrangement12 as illustrated in Scheme 1B. Although the C-
alkylanilines are more stable (thermodynamically controlled
product) compared to N-alkylanilines (kinetically controlled
product), the real obstruction to this strategy is the
deamination of 4 (second step, Scheme 1B). Therefore, such
instances are very rare, the only report being by Pullarkat,
Leung, and co-workers on the corresponding allylation of
anilines using Pd and Cu catalysts.13 Recently, the higher
oxophilicity of oxo-rhenium complexes enabled their use as
efficient catalysts for direct dehydrative C−O, C−N, and C−C
bond formation from π-activated alcohols.14,15b Such efficiency
of oxo-rhenium complexes triggered us to explore the direct FC
alkylation of anilines with benzyl alcohols. Nevertheless, the
oxo-rhenium complexes in higher oxidation states have gained
considerable attention as ecologically benign catalysts for
numerous organic reactions due to their mild reactivity, low
toxicity, and air-/moisture-tolerant nature.14−16
Scheme 1. C-Benzylation of Anilines
RESULTS AND DISCUSSION
■
Our investigations began with a survey of different catalysts as
shown in Table 1. In the reaction of 1,1-diaryl methanol (1a)
Received: December 24, 2013
Published: March 6, 2014
© 2014 American Chemical Society
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Table 1. Optimization of the Friedel−Crafts Benzylation of
Aniline
Table 2. Friedel−Crafts Benzylation of Anilines: Variation of
a,b
Anilines
a
Reaction conditions: 1 (0.1 mmol), 2 (0.12 mmol, 1.2 equiv). The
conversions and the ratio was determined by 1H NMR spectroscopy of
the reaction mixture using anisole as internal standard. In parentheses
b
a
Reaction conditions: 1 (0.5 mmol), 2 (0.6 mmol, 1.2 equiv), Re2O7
is the isolated yield.
b
(5 mol %), CH3CN (2 mL), 80 °C. Isolated yield.
and 4-nitroaniline (2a) in acetonitrile as solvent using various
Lewis acid catalysts such as Cu(OTf)2, AgSbF6, AgOTf,
Yb(OTf)3, Ce(OTf)3, Sc(OTf)3, and In(OTf)3, the formation
of the desired C-alkylated product (3a) was absent or less
compared to N-alkylated product (4) (entries 1−7, respec-
heteroaryl- and aryl-containing alcohols condensed with para or
ortho Cl-aniline to provide the corresponding C-benzylanilines
(6a−i) in good yields. Condensation of 1,1-diaryl methanols
with anilines is also equally effective for the synthesis of
corresponding C-benzylanilines (6j−o).
tively). Bronsted acids such as p-toluene sulfonic acid (pTSA)
̈
and trifluoroacetic acid (TFA) displayed similar reaction
scenarios (entries 9− and 10, respectively). Remarkably, using
Re2O7 catalyst under similar reaction conditions, the desired C-
alkylated product 3a was formed almost quantitatively and also
with excellent chemoselectivity (entry 8). Instead of acetonitrile
(with 3a:4a = 95:5), other solvents such as toluene (4:96), 1,4-
dioxane (44:56), nitromethane (92:8), methanol (61:39),
trifuoroethanol (93:7), and dichloromethane (39:61) are not
superior for the current process to provide 3a with high
chemoselectivity (over 4a).
To our excitement, even the monoaryl-containing secondary
alcohols reacted smoothly with anilines at similar reaction
conditions. For examples, various 2-thiophene-containing
secondary alcohols provided the corresponding C-benzylani-
lines (6q−s) in good yields. The corresponding 1-furanyl-1-
ethyl methanol also gave C-benzylanilines (6t). These examples
directly reflect the advantage of current strategy over the
hydroarylation processes where the styrenes provided only
methyl substitution on the benzylic position of anilines.4
Further, primary aryl or heteroaryl methanols, where the
Hofmann−Martius rearrangement process is challenging, have
also been utilized successively as electrophiles for the current
process. In this context, heteroaryl-containing primary alcohols
such as 2-thiophenylmethan-1-ol and 2-pyrrolylmethan-1-ol as
well as methoxy benzyl alcohols provided the corresponding C-
alkylated anilines with somewhat acceptable yields (6u−x,
Table 3), even under similar reaction conditions, except in a
few cases where increase in the reaction temperature was
required (6t−x).
Interestingly, even lower loading of Re2O7 catalyst (1.5 mol
%) at 60 °C is sufficient to activate the corresponding
substituted allyl and propargyl alcohols to provide the
corresponding 2-substituted anilines from anilines in excellent
chemoselectivity as well as good yields (8a−h), as shown in
Table 4. Notably, the anilines with electron-deficient
substituents such as 4-NO2-, 4-EtO2C-, 4-CN-, 4-F3C-, and 4-
F- also provided the corresponding C-allylanilines in good
yields (8a−e, respectively). This result represented a major
advancement over the previous protocol reported by Pullarkat,
Leung, and co-workers13 where 4-NO2- and 4-EtO2C-anilines
provided the corresponding N-allylanilines only. Notably, to the
The optimized reaction conditions proved to be effective for
a wide range of substituted anilines, including those with
electron-rich as well as electron-deficient substituents (see
Table 2). Various mono-, di-, or tri-substituted anilines, with
ortho, meta, and para substitution patterns, furnished the
desired products in good yields (3a−3s). Interestingly, the
regioselective formation of only p-benzylanilines (3k−n) was
observed from anilines with the para-position being vacant.
Notably, the slower rate is observed for ortho-benzylated
products compared to para-benzylated ones (for example, the
cases such as 3a vs 3l, 3i vs 3m, and 3j vs 3n); the slower rate is
mainly attributable to the effect of steric hindrance at the ortho-
position. Gratifyingly, the electron-deficient anilines with
substituents such as 4-NO2-, 4-EtO2C-, 4-CN-, 4-F3C-, and 4-
F-, which are considered to be prototypically deactivated
anilines and usually provide N-alkylated products on
alkylation,4 also provided the corresponding C-benzylanilines
in good yields (3a−e, respectively).
To broaden the substrate scope, we carried out the reaction
of various aryl-heteroaryl as well as diaryl alcohols with
substituted anilines (see Table 3). Various combinations of
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a,b
Table 3. Friedel−Crafts Benzylation of Anilines: Variation of Alcohols
a
b
Reaction conditions: 1 (0.5 mmol), 2 (0.6 mmol, 1.2 equiv), Re2O7 (5 mol %), CH3CN (2 mL), 80 °C. Isolated yield after column
c
chromatography. Reaction was performed at 100 °C using 5 mol % Re2O7.
Table 4. Friedel−Crafts Allylation and Propargylation of
Scheme 2. Stepwise Reaction Pathway
a,b
Anilines
nucleophilicity of 4-nitroaniline (2a), the in situ formed
corresponding benzylic carbocation (generated from 4a)
undergoes partial decomposition to provide an unidentified
complex mixture, whereas 4-nitroaniline (2a) remained
unreactive.
To understand whether the current rearrangements proceed
through an inter- or intramolecular pathway, the following
crossover experiment was performed (Scheme 3). The
treatment of N-benzylaniline (4a) in the presence of 4-
cyanoaniline (2c), an alternative Friedel−Crafts coupling
partner, under our specified reaction conditions using 5 mol
% Re2O7, a mixture of C-benzylanilines (3a and 3c) was
obtained. This indicates the dissociative reversible nature of this
rearrangement and the formation of a carbocation intermediate.
a
Reaction conditions: 1 (0.5 mmol), 2 (0.6 mmol, 1.2 equiv), Re2O7
b
(1.5 mol %), CH3CN (2 mL), 60 °C. Isolated yield after column
chromatography. 5 mol % catalyst was used in MeNO2 as solvent.
c
best of our knowledge this is the first report of C-
propargylation of anilines using substituted propargyl alcohol.
To gain insight into the reaction mechanism of the current
benzylation of anilines using Re2O7 as catalyst, N-benzylaniline
4a was treated under our standard reaction conditions using
Re2O7 catalyst (5 mol %) (Scheme 2). As expected, the
formation of C-benzylaniline 3a was clearly observed. Here, the
reduced isolated yield of 3a in comparison to the same in Table
2 is probably because of the excess use of nucleophile, 4-
nitroaniline, in Table 2. Also, because of the poor
Scheme 3. Crossover Experiment
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As shown in Scheme 4, an enantiorich benzyl alcohol (−)-7
with 71% ee was treated with aniline 2m under our optimized
corresponding 1a. After 20 min, the signal for 4a appeared
along with a small signal of low intensity at δ = 5.70 ppm
corresponding to the formation of 3a; this reflects that the
formation of 4a is faster compared to the formation of 3a.
Eventually, the concentration of 3a started increasing in parallel
with the decreasing concentration of 1a. Finally, the spectra
obtained is for the product 3a exclusively.
Scheme 4. Friedel−Crafts Benzylation of Aniline of Chiral
Benzyl Alcohol
Based on the above studies, the proposed mechanism for the
current benzylation of anilines is depicted below (Scheme 5).
Scheme 5. Proposed Mechanism
reaction conditions, and the racemic C-benzylaniline 6q was
obtained. This result also suggests the formation of a
carbocationic intermediate (SN1-like mechanism) from chiral
alcohol (−)-7 during the reaction process.
To gain further insight into the mechanism of this Re2O7
catalysis, the reaction between benzyl alcohol 1a and 4-
1
nitroaniline (2a) was monitored by H NMR spectroscopy. In
1
the H NMR spectra of benzyl alcohol 1a, N-benzylaniline 4a,
and C-benzylaniline 3a taken in acetonitrile-d3, the distinguish-
able signal of benzylic CH proton appeared at δ = 6.02, 6.01−
5.95, and 5.70 ppm, respectively. As shown in Figure 1, the
monitoring of the reaction between 1a and 2a in acetonitrile-d3
at 80 °C revealed that immediately after the mixing (at 0 min)
of 1a and 2a, the only signal observed cleanly was for
The strong oxophilicity14d of Re2O7 enabled the formation of
carbocation B, which simultaneously is trapped to give N-
alkylation product 4 (a kinetically controlled product) as well as
C-alkylation product 3 (a thermodynamically controlled
product) with anilines. Further activation of N-alkyl product
by Re2O7 again generated the carbocation B and followed the
previous reaction cycle. This also indicates that oxo-rhenium
complexes could be an efficient catalyst for the activation of a π-
activated C−N bond.
CONCLUSION
■
In conclusion, a catalytic approach for the synthesis of highly
substituted C-benzylanilines has been developed using
unprotected anilines and aryl and/or heteroaryl alcohols with
Re2O7 as catalyst under an open-flask reaction condition. This
offers a significant advantage over the previous protocols for the
synthesis of C-benzylanilines. Excellent chemoselective for-
mation of C-alkylated over N-alkylated products were observed.
The mechanistic studies revealed that the probable formation of
N-alkylanilines followed by Martius rearrangement to provide
C-alkylanilines as well as the dehydrative formation of C-
alkylanilines occurred. Further developments of catalytic
reactions where anilines are directly used as substrate are our
current focus.
EXPERIMENTAL SECTION
■
General Remarks. All reagents and solvents were used as supplied
commercially. Commercial Re2O7, ranging in color from yellow to
brown-black, was stored in a desiccator over CaCl2. Reactions were
conducted in open atmosphere. Analytical thin-layer chromatography
(TLC) was performed on 0.2 mm coated Science silica gel EM 60-
F254 plates. Visualization was accomplished with UV light (254 nm)
and exposure to either ethanolic phosphomolybdic acid (PMA),
anisaldehyde, or KMnO4 solution followed by heating. Melting points
are uncorrected. 1H NMR spectra were acquired on a 400 MHz
spectrometer, and chemical shifts are reported relative to the residual
Figure 1. Monitoring the gradual change in the concentrations of the
1
C−N and C−C products by H NMR spectra at 80 °C.
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solvent peak. 13C NMR spectra were acquired on a 100 MHz
spectrometer, and chemical shifts are reported in ppm relative to the
residual solvent peak. Unless noted, NMR spectra were acquired in
CDCl3; individual peaks are reported as multiplicity (s = singlet, d =
doublet, t = triplet, q = quartet, m = multiplet), integration, coupling
constant in hertz. All IR spectra were obtained as neat films, and
selected absorbances are reported in cm−1. Low resolution (LR) and
high-resolution (HR) data were acquired using either a Daltonics
Micro TOF-Q-II Mass Spectrometer or a GC Q-TOF Mass
Spectrometer or by GC−MS (EI 70 eV) using DB-5 column.
Standard Procedure for the Synthesis of Benzyl Anilines. To
a stirred solution of alcohol (0.5 mmol) and aniline (0.6 mmol) in
CH3CN (2.0 mL), in a round-bottom flask attached to a reflux
condenser, was added Re2O7 (5 mol %). Unless otherwise noted, the
reaction was stirred at 80 °C for the given time in Schemes 2 and 3.
The reaction was quenched with the addition of brine solution (2 mL),
followed by extraction with EtOAc (3 × 10 mL). The combined
organic layer was dried over anhydrous MgSO4. The solvent was
removed under vacuum, and the crude residue was purified by flash
column chromatography (EtOAc/hexane) on silica gel.
Characterization Data. 4-Nitro-2-(phenyl(thiophen-2-yl)-
methyl)aniline (3a). 0.111 g, 72% yield; Rf = 0.30 (20:80 =
EtOAc/n-hexane); dark solid; mp 150−155 °C; FT-IR (neat) 3480,
3383, 3247, 3065, 2924, 1627, 1602, 1580, 1488,1452, 1434, 1301,
1155, 1094, 915, 829, 751 cm−1; 1H NMR (400 MHz, CDCl3) δ 8.01
(dd, J = 8.8, 2.4 Hz, 1H), 7.74 (d, J = 2.4 Hz, 1H), 7.37−7.30 (m, 3H),
7.27 (dd, J = 5.2, 0.8 Hz, 1H), 7.19 (d, J = 7.2 Hz, 2H), 6.97 (dd, J =
5.2, 3.6 Hz, 1H), 6.73 (d, J = 3.6 Hz, 1H), 6.64 (d, J = 8.8 Hz, 1H),
5.56 (s, 1H), 4.25 (s, 2H); 13C NMR (100 MHz, CDCl3) δ 150.3,
144.3, 140.5, 139.4, 129.1, 128.6, 127.8, 127.7, 127.17, 127.14, 125.9,
125.6, 124.6, 114.9, 47.2; HRMS (ESI, m/z) [M + H]+ calculated for
C17H15N2O2S 311.0854, found 311.0846.
HRMS (ESI, m/z) [M + H]+ calculated for C18H15F3NS 334.0877,
found 334.0873.
4-Fluoro-2-(phenyl(thiophen-2-yl)methyl)aniline (3e). 0.102
g, 72% yield; Rf = 0.33 (10:90 = EtOAc/hexane); brown solid; mp
70−75 °C; FT-IR (neat) 3446, 3362, 3062, 2923, 1625, 1495, 1451,
1432, 1258, 1230, 1197, 1144, 1076, 1030, 961, 881, 816, 699 cm−1;
1H NMR (400 MHz, CDCl3) δ 7.34 (2H), 7.29 (d, J = 6.8 Hz, 1H),
7.24 (dd, J = 5.2, 1.2 Hz, 1H), 7.21 (d, J = 7.2 Hz, 2H), 6.96 (dd, J =
5.2, 3.6 Hz, 1H), 6.81 (td, J = 8.3, 2.9 Hz, 1H), 6.72 (d, J = 3.6 Hz,
1H), 6.61 (dd, J = 8.4, 4.8 Hz, 1H), 6.56 (dd, J = 10.0, 2.8 Hz, 1H),
5.65 (s, 1H), 3.38 (br, 2H); 13C NMR (100 MHz, CDCl3) δ two
signals: 157.7 and 155.4 (d, J = 2.34 Hz), 145.7, 141.7, two signals:
140.10 and 140.08 (d, J = 2 Hz), two signals: 131.0 and 130.9 (d, J = 6
Hz), two signals: 128.87 and 128.84 (d, J = 3 Hz), 127.3, two signals:
126.92 and 126.86 (d, J = 6 Hz), 125.1, two signals: 117.28 and 117.21
(d, J = 7 Hz), two signals: 116.1 and 115.8 (d, J = 24 Hz), two signals:
114.32 and 114.09 (d, J = 23 Hz), 47.2; HRMS (ESI, m/z) [M + H]+
calculated for C17H15FNS 284.0909, found 284.0894.
4-Methyl-2-(phenyl(thiophen-2-yl)methyl)aniline (3f). 0.103
g, 74% yield; Rf = 0.32 (10:90 = EtOAc/n-hexane); brown solid; mp
75−80 °C; FT-IR (neat) 3435, 3361, 3026, 2921, 2859, 2363, 1732,
1
1626, 1505, 1452, 1266, 1156, 1076, 1040, 817, 700 cm−1; H NMR
(400 MHz, CDCl3) δ 7.33 (d, J = 7.6 Hz, 2H), 7.29 (d, J = 6.8 Hz,
1H), 7.24 (d, J = 6.4 Hz, 3H), 6.97 (dd, J = 5.2, 3.6 Hz, 1H), 6.92 (d, J
= 8.0 Hz, 1H), 6.74 (d, J = 3.2 Hz, 1H), 6.65 (s, 1H), 6.61 (d, J = 8.0
Hz, 1H), 5.69 (s, 1H), 3.40 (br s, 2H), 2.19 (s, 3H); 13C NMR (100
MHz, CDCl3) δ 146.7, 142.5, 141.6, 129.7, 129.3, 128.9, 128.6, 128.3,
128.0, 127.0, 126.7, 126.6, 124.8, 116.6, 47.2, 20.8; HRMS (ESI, m/z)
[M + H]+ calculated for C18H18NS 280.1160 , found 280.1135.
4-Methoxy-2-(phenyl(thiophen-2-yl)methyl)aniline (3g).
0.100 g, 68% yield; Rf = 0.40 (20:80 = EtOAc/hexane); light yellow
liquid; FT-IR (neat) 3426, 3355, 3062, 3026, 2998, 2928, 2853, 2831,
1608, 1497, 1452, 1403, 1322, 1277, 1227, 1155, 1130, 1075, 816
cm−1; 1H NMR (400 MHz, CDCl3) δ 7.33−7.39 (m, 2H), 7.28−7.25
(m, 1H), 7.22 (d, J = 5.6 Hz, 3H), 6.94 (dd, J = 4.8, 3.6 Hz, 1H), 6.72
(d, J = 3.6 Hz, 1H), 6.68 (dd, J = 8.4, 2.8 Hz, 1H), 6.63 (d, J = 8.4 Hz,
1H), 6.45 (dJ = 2.4 Hz, 1H), 5.69 (s, 1H), 3.64 (s, 3H), 3.00 (br s,
2H); 13C NMR (100 MHz, CDCl3) δ 152.9, 146.3, 142.2, 137.6,
131.1, 128.9, 128.7, 127.1, 126.79, 126.75, 124.9, 117.5, 115.9, 112.4,
55.5, 47.3; HRMS (ESI, m/z) [M + H]+ calculated for C18H18NOS
296.1109, found 296.1100.
Ethyl 4-Amino-3-(phenyl(thiophen-2-yl)methyl)benzoate
(3b). 0.130 g, 77% yield; Rf = 0.36 (20:80 = EtOAc/n-hexane);
white solid; mp 130−135 °C; FT-IR (neat) 3406, 3359, 3068, 2982,
2357, 1694, 1605, 1505, 1392, 1285, 1238, 1150, 1110, 1029, 836, 770,
1
736 cm−1; H NMR (400 MHz, CDCl3) δ 7.79 (dd, J = 8.4, 1.6 Hz,
1H), 7.56 (d, J = 1.6 Hz, 1H), 7.31 (d, J = 7.2 Hz, 2H), 7.28 (d, J = 6.8
Hz, 1H), 7.23 (dd, J = 5.2, 1.2 Hz, 2H), 7.20 (s, 1H), 6.95 (dd, J = 4.8,
3.2 Hz, 1H), 6.72 (d, J = 3.6 Hz, 1H), 6.64 (d, J = 8.4 Hz, 1H), 5.60 (s,
1H), 4.24 (q, J = 6.8 Hz, 2H), 3.94 (s, 2H), 1.28 (t, J = 7.2 Hz, 3H);
13C NMR (100 MHz, CDCl3) δ 166.8, 148.6, 145.5, 141.5, 131.4,
129.9, 128.83, 128.81, 127.6, 127.3, 126.9, 126.8, 125.1, 120.3, 115.3,
60.3, 47.4, 14.3; HRMS-GC (EI, m/z) [M]+ calculated for
C20H19NO2S 337.1136, found 337.1109.
4-(Methylthio)-2-(phenyl(thiophen-2-yl)methyl)aniline (3h).
0.118 g, 76% yield; Rf = 0.34 (20:80 = EtOAc/n-hexane); brown solid;
mp 70−75 °C; FT-IR (neat) 3437, 3365, 3025, 2917, 1621, 1488,
1451, 1435, 1405, 1310, 1282, 1229, 1148, 1110, 1030, 968, 817 cm−1;
1H NMR (400 MHz, CDCl3) δ 7.34−7.30 (m, 2H), 7.27 (d, J = 7.2
Hz, 1H), 7.23−7.19 (m, 3H), 7.10 (dd, J = 8.0, 2.0 Hz, 1H), 6.95 (dd,
J = 5.2, 3.6 Hz, 1H), 6.83 (d, J = 2.4 Hz, 1H), 6.71 (d, J = 3.6 Hz, 1H),
6.62 (d, J = 8.0 Hz, 1H), 5.62 (s, 1H), 3.50 (s, 2H), 2.30 (s, 3H); 13C
NMR (100 MHz, CDCl3) δ 145.9, 142.7, 141.9, 130.5, 129.9, 128.98,
128.90, 128.7, 127.2, 126.8, 126.2, 125.0, 117.0, 47.2, 18.3; HRMS
(ESI, m/z) [M]+ calculated for C18H17NS2 311.0802, found 311.0811.
4-Chloro-2-(phenyl(thiophen-2-yl)methyl)aniline (3i). 0.096
g, 64% yield; Rf = 0.43 (20:80 = EtOAc/hexane); light yellow liquid;
FT-IR (neat) 3447, 3369, 3061, 3026, 2918, 1622, 1488, 1451, 1413,
4-Amino-3-(phenyl(thiophen-2-yl)methyl)benzonitrile (3c).
0.120 g, 83% yield; Rf = 0.24 (20:80 = EtOAc/n-hexane); dark
solid; mp 135−140 °C; FT-IR (neat) 3477, 3375, 3059, 2952, 2365,
2218, 1627, 1603, 1503, 1452, 1306, 1210, 1156, 1110, 1077, 1038,
1
908, 826, 735 cm−1; H NMR (400 MHz, CDCl3) δ 7.36−7.29 (m,
4H), 7.26−7.24 (m, 1H), 7.16 (d, J = 6.8 Hz, 2H), 7.04 (d, J = 1.2 Hz,
1H), 6.96 (dd, J = 5.2, 3.6 Hz, 1H), 6.70 (d, J = 3.2 Hz, 1H), 6.65 (d, J
= 8.0 Hz, 1H), 5.54 (s, 1H), 4.04 (s, 2H); 13C NMR (100 MHz,
CDCl3) δ 148.3, 144.5, 140.7, 133.5, 132.1, 129.0, 128.7, 128.6, 127.7,
127.1, 127.0, 125.5, 120.2, 115.8, 100.5, 46.9; HRMS (ESI, m/z) [M +
H]+ calculated for C18H15N2S 291.0956, found 291.0956.
1
1283, 1230, 1142, 1076, 1030, 905, 815, 744 cm−1; H NMR (400
MHz, CDCl3) δ 7.34−7.27 (m, 3H), 7.23 (dd, J = 5.2, 1.2 Hz, 1H),
7.18 (d, J = 6.8 Hz, 2H), 7.04 (dd, J = 8.4, 2.4 Hz, 1H), 6.95 (dd, J =
5.2, 3.6 Hz, 1H), 6.76 (d, J = 2.4 Hz, 1H), 6.70 (d, J = 3.6 Hz, 1H),
6.62 (d, J = 8.4 Hz, 1H), 5.61 (s, 1H), 3.67 (br s, 2H); 13C NMR (100
MHz, CDCl3) δ 145.4, 142.3, 141.5, 130.9, 129.0, 128.84, 128.84,
127.7, 127.3, 126.92, 126.90, 125.2, 123.9, 117.7, 47.1; HRMS (ESI,
m/z) [M + H]+ calculated for C17H15ClNS 300.0614, found 300.0595.
4-Bromo-2-(phenyl(thiophen-2-yl)methyl)aniline (3j). 0.099
g, 58% yield; Rf = 0.32 (10:90 = EtOAc/hexane); brown liquid; FT-IR
(neat) 3446, 3370, 3025, 1621, 1485, 1451, 1408, 1282, 1075, 894,
2-(Phenyl(thiophen-2-yl)methyl)-4-(trifluoromethyl)aniline
(3d). 0.132 g, 79% yield; Rf = 0.24 (10:90 = EtOAc/hexane); brown
solid; mp 80−85 °C; FT-IR (neat) 3470, 3388, 3065, 2924, 2852,
1628, 1509, 1452, 1434, 1328, 1303, 1246, 1151, 1112, 1078, 910, 826,
1
744, 699 cm−1; H NMR (400 MHz, CDCl3) δ 7.40−7.36 (m, 3H),
7.35−7.32 (m, 1H), 7.29 (dd, J = 5.2, 1.0 Hz, 1H), 7.25 (d, J = 1.5 Hz,
1H), 7.23 (s, 1H), 7.09 (d, J = 1.5 Hz, 1H), 7.01 (dd, J = 5.5, 3.5 Hz,
1H), 6.76−6.75 (m, 1H), 6.74 (d, J = 8.3 Hz, 1H), 5.66 (s, 1H), 3.87
(s, 2H); 13C NMR (100 MHz, CDCl3) δ 147.1, 145.2, 141.2, 128.90,
128.8, 128.4, 127.5, 127.0, four signals: 126.46, 126.43, 126.40, 126.30
(q, J = 3 Hz), 125.34, four signals: 125.20, 125.16, 125.13, and 125.10
(q, J = 3 Hz), two signals: 125.84 and 123.69 (d, J = 268 Hz), four
signals: 120.73, 120.47, 120.21, and 119.96 (q, J = 26 Hz), 115.7, 47.2;
1
814, 745, 699 cm−1; H NMR (400 MHz, CDCl3) δ 7.34−7.30 (m,
2H), 7.29−7.27 (m, 1H), 7.23 (d, J = 0.8 Hz, 1H), 7.20−7.16 (m,
3H), 6.95 (dd, J = 5.2, 3.6 Hz, 1H), 6.89 (d, J = 2.0 Hz, 1H), 6.70 (d, J
= 3.6 Hz, 1H), 6.55 (d, J = 8.4 Hz, 1H), 5.59 (s, 1H), 3.52 (s, 2H); 13C
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NMR (100 MHz, CDCl3) δ 145.4, 143.2, 141.5, 131.8, 131.1, 130.6,
128.85, 128.83, 127.3, 126.92, 126.90, 125.2, 117.9, 110.8, 47.1;
HRMS (ESI, m/z) [M + H]+ calculated for C17H15BrNS 344.0109,
found 344.0106.
yellow liquid; FT-IR (neat) 3452, 3376, 3061, 2924, 2363, 1624, 1475,
1
1425, 1267, 1228, 1078, 967, 871, 853, 700 cm−1; H NMR (400
MHz, CDCl3) δ 7.36−7.32 (m, 2H), 7.29 (d, J = 6.8 Hz, 1H), 7.24
(dd, J = 4.8, 0.8 Hz, 1H), 7.18 (d, J = 6.8 Hz, 2H), 7.10 (dd, J = 10, 2.4
Hz, 1H), 6.95 (dd, J = 4.8, 3.6 Hz, 1H), 6.71 (dd, J = 3.2, 2.0 Hz, 2H),
5.62 (s, 1H), 3.57 (s, 2H); 13C NMR (100 MHz, CDCl3) δ two
signals: 152.99 and 150.57 (d, J = 242 Hz), 144.85, 141.02, two
signals: 132.81 and 132.78 (d, J = 3 Hz), two signals: 131.98, and
131.85 (d, J = 13 Hz), two signals: 129.20 and 128.43 (d, J = 77 Hz),
128.95, 128.74, 127.56, two signals: 127.34 and 127.31 (d, J = 3 Hz),
two signals: 126.99 and 126.98 (d, J = 1 Hz), 125.40, two signals:
117.19 and 116.97 (d, J = 22 Hz), two signals: 108.99 and 108.89 (d, J
= 10 Hz), 47.07; HRMS (ESI, m/z) [M − H]+ calculated for
C17H12BrFNS 359.9858, found 359.9859.
4-(Phenyl(thiophen-2-yl)methyl)aniline (3k). 0.99 g, 75% yield;
Rf = 0.34 (05:95 = EtOAc/hexane); brown liquid; FT-IR (neat) 3448,
3370, 3219, 3060, 1621, 1513, 1493, 1451, 1435, 1279, 1228, 1181,
1107, 1076, 819, 699 cm−1; 1H NMR (400 MHz, CDCl3) δ 7.29 (d, J
= 7.2 Hz, 2H), 7.23−7.21 (m, 3H), 7.19 (dd, J = 5.2, 1.4 Hz, 1H), 7.00
(d, J = 8.3 Hz, 2H), 6.93 (dd, J = 5.2, 3.6 Hz, 1H), 6.69 (d, J = 3.2 Hz,
1H), 6.62 (d, J = 8.4 Hz, 2H), 5.58 (s, 1H), 3.59 (br, 2H); 13C NMR
(100 MHz, CDCl3) δ 148.8, 145.0, 144.4, 134.0, 129.7, 128.8, 128.3,
126.55, 126.54, 126.1, 124.3, 115.1, 51.4; HRMS (ESI, m/z) [M + H]+
calculated for C17H16NS 266.1003, found 266.1019.
3,4,5-Trimethoxy-2-(phenyl(thiophen-2-yl)methyl)aniline
(3r). 0.144 g, 81% yield; Rf = 0.33 (20:80 = EtOAc/hexane); light
yellow liquid; FT-IR (neat) 3436, 3357, 2935, 2838, 2116, 1623, 1604,
4-Nitro-2-(phenyl(thiophen-2-yl)methyl)aniline (3l). 0.126 g,
81% yield; Rf = 0.30 (10:90 = EtOAc/hexane); yellow solid; mp 130−
140 °C; FT-IR (neat) 3485, 3383, 3245, 3065, 2928, 1627, 1602, 1575,
1
1495, 1455, 1360, 1299, 1196, 1117, 1033, 998, 823, 728 cm−1; H
1
1488, 1477, 1434, 1301, 1155, 1099, 915, 829, 758 cm−1; H NMR
NMR (400 MHz, CDCl3) δ 7.35−7.28 (m, 4H), 7.23 (d, J = 7.2 Hz,
1H), 7.20 (dd, J = 5.2, 0.8 Hz, 1H), 6.93 (dd, J = 5.2, 3.6 Hz, 1H), 6.87
(d, J = 3.6 Hz, 1H), 6.24 (s, 1H), 5.99 (s, 1H), 3.81 (s, 3H), 3.79 (s,
3H), 3.68 (s, 3H), 3.36 (br s, 2H); 13C NMR (100 MHz, CDCl3) δ
153.0, 152.4, 146.8, 142.4, 141.6, 134.7, 128.4, 128.3, 126.6, 126.5,
126.2, 124.5, 114.5, 96.9, 61.1, 61.0, 55.6, 41.9; HRMS (EI, m/z) [M +
H]+ calculated for C20H22NO3S 356.1320, found 356.1341.
(400 MHz, CDCl3) δ 7.95 (d, J = 1.9 Hz, 1H), 7.31 (t, J = 7.2 Hz,
2H), 7.26 (s, 1H), 7.21 (dd, J = 10.6, 4.6 Hz, 4H), 6.94 (dd, J = 5.1,
3.6 Hz, 1H), 6.71 (dd, J = 20.2, 6.0 Hz, 2H), 6.07 (s, 2H), 5.58 (s,
1H); 13C NMR (100 MHz, CDCl3) δ 147.0, 143.5, 142.9, 136.3,
132.9, 131.8, 128.65, 128.65, 127.0, 126.7, 126.4, 125.6, 124.9, 119.0,
50.8; HRMS (ESI, m/z) [M + H]+ calculated for C17H15N2O2S
311.0854, found 311.0846
3-(Phenyl(thiophen-2-yl)methyl)-9H-fluoren-2-amine (3s).
0.138 g, 78% yield; Rf = 0.42 (10:90 = EtOAc/hexane); brown
solid; mp 125−130 °C; FT-IR (neat) 3441, 3367, 3060, 2868, 2326,
2-Chloro-4-(phenyl(thiophen-2-yl)methyl)aniline (3m). 0.123
g, 82% yield; Rf = 0.30 (05:95 = EtOAc/n-hexane); light yellow liquid;
FT-IR (neat) 3474, 3382, 3061, 3026, 1621, 1505, 1311, 1075, 699
1
1625, 1454, 1429, 1281, 1027, 852, 765 cm−1; H NMR (400 MHz,
1
cm−1; H NMR (400 MHz, CDCl3) δ 7.40−7.20 (6H), 7.14 (s, 1H),
7.02−6.92 (2H), 6.77−6.68 (2H), 5.59 (s, 1H), 4.02 (bs, 2H); 13C
NMR (100 MHz, CDCl3) δ 148.0, 143.7, 141.5, 134.8, 129.5, 128.7,
128.4, 128.1, 126.7, 126.6, 126.3, 124.6, 119.2, 115.7, 51.1; HR-MS
(ESI, m/z) [M + H]+ calculated for C17H15ClNS 300.0614, found
300.0602.
CDCl3) δ 7.46 (t, J = 7.2 Hz, 2H), 7.37−7.33 (m, 2H), 7.31−7.25 (m,
5H), 7.23 (s, 1H), 7.17 (td, J = 7.6, 0.8 Hz, 1H), 6.99 (dd, J = 4.8, 3.6
Hz, 1H), 6.87 (s, 1H), 6.78 (d, J = 3.6 Hz, 1H), 5.76 (s, 1H), 3.80 (s,
2H), 3.59 (br s, 2H); 13C NMR (100 MHz, CDCl3) δ 146.6, 143.5,
143.4, 142.5, 142.4, 142.2, 133.2, 129.0, 128.7, 128.3, 127.1, 126.85,
126.83, 126.5, 125.1, 124.9, 124.7, 120.7, 118.7, 113.1, 47.4, 36.6;
HRMS (ESI, m/z) [M + H]+ calculated for C24H20NS 354.1316,
found 354.1324.
2-Bromo-4-(phenyl(thiophen-2-yl)methyl)aniline (3n). 0.142
g, 83% yield; Rf = 0.32 (05:95 = EtOAc/hexane); clear liquid; FT-IR
(neat) 3472, 3379, 3203, 3061, 3025, 2922, 2871, 2622, 1950, 1618,
1501, 1487, 1451, 1309, 1276, 1229, 1190, 1158, 1108, 1036, 893, 746,
2-Chloro-4-(9H-thioxanthen-9-yl)aniline (6a). 0.132 g, 82%
yield; Rf = 0.29 (10:90 = EtOAc/hexane); white solid; mp 138−143
°C FT-IR (neat) 3446, 3384, 3314, 2918, 2368, 1618, 1498, 1292,
1
700 cm−1; H NMR (400 MHz, CDCl3) δ 7.31 (m, J = 7.3 Hz, 2H),
7.28−7.23 (m, 2H), 7.22−7.19 (m, J = 2.1 Hz, 3H), 6.97−6.92 (m,
2H), 6.68 (dd, J = 8.12, 1.76 Hz, 2H), 5.55 (s, 1H), 4.02 (s, 2H); 13C
NMR (100 MHz, CDCl3) δ 148.0, 143.7, 142.7, 135.2, 132.6, 128.8,
128.7, 128.4, 126.8, 126.6, 126.3, 124.6, 115.6, 109.2, 51.0; HRMS
(ESI, m/z) [M + H]+ calculated for C17H15BrNS 344.0109, found
344.0074.
1
1162, 943, 825, 796, 740, 695 cm−1; H NMR (400 MHz, CDCl3) δ
7.42 (d, J = 7.6 Hz, 2H), 7.36 (d, J = 6.8 Hz, 2H), 7.24−7.21 (m, 4H),
6.85 (s, 1H), 6.68−6.63 (dd, J = 7.6, 0.8 Hz, 1H), 6.54 (d, J = 8.4 Hz,
1H), 5.18 (s, 1H), 3.86 (br s, 2H); 13C NMR (100 MHz, CDCl3) δ
141.4, 137.2, 133.1, 131.8, 129.4, 128.6, 127.2, 127.1, 126.9, 126.6,
119.1, 115.5, 52.0; HRMS (ESI, m/z) [M + H]+ calculated for
C19H15ClNS 324.0614, found 324.0587.
6-(Phenyl(thiophen-2-yl)methyl)benzo[d][1,3]dioxol-5-
amine (3o). 0.125 g, 81% yield; Rf = 0.22 (05:95 = EtOAc/hexane);
yellow solid; mp 132−138 °C; FT-IR (neat) 3433, 3360, 3064, 2888,
2360, 1620, 1496, 1484, 1442, 1269, 1229, 1185, 1163, 1039, 934, 877,
2-Chloro-4-(9H-xanthen-9-yl)aniline (6b). 0.126 g, 82% yield;
Rf = 0.27 (10:90 = EtOAc/hexane); white solid; mp 140−143 °C FT-
IR (neat) 3446, 3384, 3314, 2900, 2378, 1638, 1498, 1292, 1162, 943,
1
829, 699 cm−1; H NMR (400 MHz, CDCl3) δ 7.34−7.30 (m, 2H),
1
825, 796, 750, 695 cm−1; H NMR (400 MHz, CDCl3) δ 7.20−7.16
7.27 (d, J = 7.2 Hz, 1H), 7.21 (s, 2H), 7.20 (s, 1H), 6.95 (dd, J = 4.8,
3.6 Hz, 1H), 6.72 (d, J = 3.2 Hz, 1H), 6.34 (s, 1H), 6.28 (s, 1H), 5.82
(d, J = 1.2 Hz, 2H), 5.62 (s, 1H), 3.33 (br s, 2H); 13C NMR (100
MHz, CDCl3) δ 146.7, 142.6, 140.5, 138.6, 128.8, 128.7, 127.0, 126.8,
126.6, 124.9, 121.9, 109.4, 100.6, 98.6, 46.8; HRMS (ESI, m/z) [M +
H]+ calculated for C18H16NO2S 310.0902, found 310.0870.
(m, 2H), 7.10 (dd, J = 7.8, 2.4 Hz, 2H), 7.06 (s, 1H), 7.02 (d, J = 7.6
Hz, 2H), 6.95 (t, J = 7.2 Hz, 2H), 6.84 (d, J = 8.0 Hz, 1H), 6.60 (d, J =
8.0 Hz, 1H), 5.09 (s, 1H), 3.89 (s, 2H); 13C NMR (100 MHz, CDCl3)
δ 151.0, 141.5, 137.6, 129.7, 129.1, 127.9, 127.7, 124.3, 123.2, 119.3,
116.6, 116.1, 43.3; HRMS (ESI, m/z) [M + H]+ calculated for
C19H15ClNO 308.0842, found 308.0824.
6-(Phenyl(thiophen-2-yl)methyl)-2,3-dihydro-1H-inden-5-
amine (3p). 0.127 g, 83% yield; Rf = 0.33 (05:95 = EtOAc/hexane);
brown solid; mp 80−85 °C; FT-IR (neat)3445, 3361, 3026, 2931,
2859, 2363, 1732, 1626, 1505, 1452, 1266, 1216, 1076, 1045, 777, 698
cm−1; 1H NMR (400 MHz, CDCl3) δ 7.33 (dd, J = 14.0, 7.2 Hz, 3H),
7.25 (dd, J = 13.2, 5.6 Hz, 3H), 6.97 (t, J = 3.6 Hz, 1H), 6.75 (s, 1H),
6.69 (s, 1H), 6.61 (s, 1H), 5.70 (s, 1H), 3.41 (br s, 2H), 2.85 (t, J = 7.2
Hz, 2H), 2.76 (t, J = 7.2 Hz, 2H), 2.07−2.00 (m, 2H); 13C NMR (100
MHz, CDCl3) δ 147.1, 143.8, 142.9, 142.4, 134.6, 129.0, 128.6, 127.6,
126.9, 126.7, 126.6, 124.8, 124.7, 112.6, 47.3, 32.8, 32.3, 25.6; HRMS
(ESI, m/z) [M + H]+ calculated for C20H20NS 306.1316, found
306.1330.
4-(Benzo[b]thiophen-2-yl(phenyl)methyl)-2-chloroaniline
(6c). 0.145 g, 83% yield; Rf = 0.28 (10:90 = EtOAc/hexane); colorless
liquid; FT-IR (neat) 3477, 3382, 3030, 2955, 2361, 2325, 1611, 1505,
1
1456, 1307, 1255, 1166, 1103, 1075, 962, 813, 755 cm−1; H NMR
(400 MHz, CDCl3) δ 7.75 (d, J = 7.6 Hz, 1H), 7.65 (d, J = 7.6 Hz,
1H), 7.36−7.32 (m, 3H), 7.30−7.26 (m, 4H), 7.17 (s, 1H), 6.98 (dd, J
= 8.4, 1.6 Hz, 1H), 6.89 (s, 1H), 6.71 (d, J = 8.4 Hz, 1H), 5.61 (s, 1H),
4.01 (s, 2H); 13C NMR (100 MHz, CDCl3) δ 148.9, 142.9, 141.7,
140.0, 139.7, 133.9, 129.7, 128.9, 128.5, 128.3, 127.0, 124.2, 123.9,
123.3, 123.1, 122.2, 119.2, 115.8, 51.8; GC-HRMS (EI, m/z) [M]+
calculated for C21H16ClNS 349.0692, found 349.0698.
4-(Benzofuran-2-yl(phenyl)methyl)-2-chloroaniline (6d).
0.130 g, 78% yield; Rf = 0.32 (10:90 = EtOAc/hexane); light yellow
4-Bromo-2-fluoro-6-(phenyl(thiophen-2-yl)methyl)aniline
(3q). 0.119 g, 66% yield; Rf = 0.31 (05:95 = EtOAc/hexane); light
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Article
liquid; FT-IR (neat) 3479, 3384, 3030, 2925, 2360, 2325, 1622, 1505,
7.22 (1H), 7.14 (d, J = 7.2 Hz, 2H), 7.10−7.00 (3H), 6.94−6.82 (3H),
1
1456, 1307, 1255, 1164, 1103, 1073, 962, 813, 750 cm−1; H NMR
6.71 (d, J = 8 Hz, 1H), 5.41 (s, 1H), 4.00 (bs, 2H), 3.82 (s, 3H); 13
C
(400 MHz, CDCl3) δ 7.52 (d, J = 7.2 Hz, 1H), 7.46 (d, J = 7.6 Hz,
1H), 7.37 (d, J = 7.6 Hz, 2H), 7.32 (d, J = 7.2 Hz, 1H), 7.27 (d, J = 8.4
Hz, 4H), 7.17 (d, J = 2.0 Hz, 1H), 6.98 (dd, J = 8.4, 2.0 Hz, 1H), 6.75
(d, J = 8.0 Hz, 1H), 6.33 (s, 1H), 5.50 (s, 1H), 4.04 (s, 2H); 13C NMR
(100 MHz, CDCl3) δ 159.9, 155.1, 141.8, 141.0, 131.9, 129.6, 128.8,
128.6, 128.4, 128.2, 127.0, 123.8, 122.6, 120.7, 119.3, 115.9, 111.2,
105.6, 50.2; GC-HRMS (EI, m/z) [M]+ calculated for C21H16ClNO
333.0920, found 333.0928.
NMR (100 MHz, CDCl3) δ 158.1, 144.2, 141.1, 136.0, 135.4, 130.2,
130.0, 129.2, 128.6, 128.3, 126.3, 119.2, 115.8, 113.7, 55.2, 54.9;
HRMS (ESI, m/z) [M + Na]+ calculated for C20H19ClNO 324.1155,
found 324.1155.
4-Chloro-2-((4-methoxyphenyl)(phenyl)methyl)aniline (6k).
0.098 g, 61% yield; Rf = 0.43 (10:90 = EtOAc/n-hexane); light yellow
liquid; FT-IR (neat) 3504, 3411, 3081, 3028, 1635, 1598, 1492, 1462,
1
1325, 1281, 1244, 1174, 1112, 1072, 1030, 973, 852, 743 cm−1; H
4-((5-Bromothiophen-2-yl)(phenyl)methyl)-2-chloroaniline
(6e). 0.147 g, 78% yield; Rf = 0.33 (10:90 = EtOAc/hexane); yellow
liquid; FT-IR (neat) 3385, 3347, 3026, 2359, 1618, 1501, 1450, 1311,
NMR (400 MHz, CDCl3) δ 7.32−7.28 (m, 2H), 7.26−7.22 (m, 1H),
7.09 (d, J = 6.8 Hz, 2H), 7.04−7.00 (m, 3H), 6.84 (d, J = 8.4 Hz, 2H),
6.61−6.59 (2H), 5.36 (s, 1H), 3.79 (s, 3H), 3.45 (br s, 2H); 13C NMR
(100 MHz, CDCl3) δ 158.4, 142.7, 142.0, 133.6, 131.2, 130.3, 129.6,
129.34, 128.7, 127.2, 126.9, 123.5, 117.3, 114.1, 55.2, 51.3; HRMS
(ESI, m/z) [M + H]+ calculated for C20H19ClNO 324.1155, found
324.1151.
2-(Bis(4-methoxyphenyl)methyl)-4-chloroaniline (6l). 0.145
g, 82% yield; Rf = 0.37 (10:90 = EtOAc/hexane); brown liquid; FT-
IR (neat) 3449, 3371, 3001, 2955, 2836, 1610, 1582, 1509, 1488, 1464,
1411, 1302, 1282, 1247, 1177, 1141, 1111, 1033, 909, 873, 734 cm−1;
1H NMR (400 MHz, CDCl3) δ 7.01 (d, J = 8.4 Hz, 5H), 6.84 (d, J =
8.4 Hz, 4H), 6.62 (d, J = 2.0 Hz, 1H), 6.58 (d, J = 8.4 Hz, 1H), 5.31 (s,
1H), 3.78 (s, 6H), 3.41 (br s, 2H); 13C NMR (100 MHz, CDCl3) δ
158.4, 142.7, 134.0, 131.5, 130.3, 129.5, 127.2, 123.4, 117.3, 114.1,
55.2, 50.5; HRMS (ESI, m/z) [M + H]+ calculated for C21H21ClNO2
354.1261, found 354.1257.
4-Chloro-2-((3,4-dimethoxyphenyl)(4-methoxyphenyl)-
methyl)aniline (6m). 0.155 g, 81% yield; Rf = 0.38 (40:60 = EtOAc/
hexane); brown solid; mp 50−55 °C; FT-IR (neat) 3447, 3368, 3000,
2934, 2835, 1609, 1509, 1489, 1464, 1412, 1248, 1177, 1139, 1110,
1028, 954, 907, 814, 782, 757, 736 cm−1; 1H NMR (400 MHz,
CDCl3) δ 7.00 (d, J = 8.4 Hz, 3H), 6.83 (d, J = 88 Hz, 2H), 6.77 (d, J
= 8.4 Hz, 1H), 6.62 (dd, J = 13.2, 2.0 Hz, 2H), 6.56 (d, J = 8.4 Hz,
2H), 5.28 (s, 1H), 3.83 (s, 3H), 3.76 (s, 3H), 3.74 (s, 3H), 3.43 (br s,
2H); 13C NMR (100 MHz, CDCl3) δ 158.4, 149.1, 147.8, 142.9,
134.5, 133.8, 131.4, 130.2, 129.4, 127.2, 123.3, 121.3, 117.2, 114.1,
112.6, 111.1, 55.86, 55.86, 55.2, 50.9; HRMS (ESI, m/z) [M + H]+
calculated for C22H22ClNNaO3 406.1186, found 406.1180.
1
1212, 1157, 1047, 963, 886, 797, 738 cm−1; H NMR (400 MHz,
CDCl3) δ 7.31−7.28 (m, 2H), 7.24 (d, J = 4.8 Hz, 1H), 7.17 (d, J = 7.2
Hz, 2H), 7.06 (d, J = 2 Hz, 1H), 6.88 (dd, J = 8, 2.0 Hz, 1H), 6.86 (d, J
= 3.6 Hz, 1H), 6.68 (d, J = 8.4 Hz, 1H), 6.41 (dd, J = 3.6, 0.8 Hz, 1H),
5.42 (s, 1H), 3.96 (s, 2H); 13C NMR (100 MHz, CDCl3) δ 149.7,
142.8, 141.7, 133.9, 129.5, 129.4, 128.6, 128.5, 128.0, 127.0, 126.5,
119.2, 115.7, 111.0, 51.3; GC-HRMS (EI, m/z) [M]+ calculated for
C17H13BrClNS 376.9641, found 376.9644.
4-((4-Methoxyphenyl)(thiophen-2-yl)methyl)aniline (6f).
0.122 g, 83% yield; Rf = 0.25 (20:80 = EtOAc/hexane); orange
solid; mp 105−110 °C; FT-IR (neat) 3444, 3368, 2925, 2854, 2361,
1
1618, 1458, 1246, 1176, 1108, 1031, 822, 699 cm−1; H NMR (400
MHz, CDCl3) δ 7.18 (dd, J = 4.8, 0.8 Hz, 1H), 7.14 (d, J = 8.4 Hz,
2H), 7.00 (d, J = 8.4 Hz, 2H), 6.93 (dd, J = 4.8, 3.6 Hz, 1H), 6.84 (d, J
= 8.8 Hz, 2H), 6.69 (d, J = 3.6 Hz, 1H), 6.62 (d, J = 8.4 Hz, 2H), 5.54
(s, 1H), 3.79 (s, 3H), 3.59 (br s, 2H); 13C NMR (100 MHz, CDCl3) δ
158.2, 149.4, 145.0, 136.7, 134.3, 129.7, 129.6, 126.5, 125.9, 124.2,
115.1, 113.7, 55.2, 50.6; HRMS (ESI, m/z) [M + H]+ calculated for
C18H18NOS 296.1109, found 296.1123.
4-Chloro-2-((4-methoxyphenyl)(thiophen-2-yl)methyl)-
aniline (6g). 0.135 g, 82% yield; Rf = 0.34 (20:80 = EtOAc/hexane);
yellow liquid; FT-IR (neat) 3445, 3369, 3001, 2959, 2931, 2836, 1621,
1583, 1509, 1488, 1440, 1413, 1248, 1178, 1142, 1033, 907, 838, 762
1
cm−1; H NMR (400 MHz, CDCl3) δ 7.22 (dd, J = 5.2, 1.2 Hz, 1H),
7.10 (d, J = 8.4 Hz, 2H), 7.03 (dd, J = 8.4, 2.4 Hz, 1H), 6.94 (dd, J =
5.2, 3.6 Hz, 1H), 6.85 (d, J = 8.4 Hz, 2H), 6.76 (d, J = 2.0 Hz, 1H),
6.69 (d, J = 3.6 Hz, 1H), 6.60 (d, J = 8.4 Hz, 1H), 5.55 (s, 1H), 3.79
(s, 3H), 3.36 (br s, 2H); 13C NMR (100 MHz, CDCl3) δ 158.7, 146.0,
142.5, 133.5, 131.1, 129.8, 128.9, 127.6, 126.9, 126.6, 125.1, 123.7,
117.5, 114.2, 55.2, 46.3; HRMS (ESI, m/z) [M + H]+ calculated for
C18H17ClNOS 330.0719, found 330.0729.
2-((2,3-Dihydrobenzo[b][1,4]dioxin-6-yl)(4-methoxyphenyl)-
methyl)-4-methoxyaniline (6n). 0.128 g, 68% yield; Rf = 0.26
(20:80 = EtOAc/hexane); light yellow liquid; FT-IR (neat) 3428,
3358, 2984, 2934, 2835, 2364, 1737, 1610, 1509, 1465, 1401, 1370,
1
1328, 1248, 1158, 1117, 1063, 1037, 892, 837, 771 cm−1; H NMR
4-((1H-Indol-3-yl)(phenyl)methyl)-2-chloroaniline (6h). 0.134
(400 MHz, CDCl3) δ 7.02 (d, J = 8.8 Hz, 2H), 6.81 (d, J = 8.8 Hz,
2H), 6.76 (2H), 6.63−6.56 (m, 3H), 6.30 (s, 1H), 5.32 (s, 1H), 4.21
(s, 4H), 3.77 (s, 3H), 3.62 (s, 3H). 3.44 (br s, 2H); 13C NMR (100
MHz, CDCl3) δ 158.2, 152.9, 143.4, 142.2, 137.3, 135.9, 134.4, 131.9,
130.3, 122.4, 118.1, 117.2, 116.7, 114.8, 113.9, 111.6, 64.33, 64.31,
55.5, 55.2, 50.7; HRMS (ESI, m/z) [M + H]+ calculated for
C23H24NO4 378.1705, found 378.1686.
g, 81% yield; Rf = 0.20 (20:80 = EtOAc/hexane); pink liquid; FT-IR
1
(neat) 3419, 3056, 3024, 1620, 1501, 1455, 1094, 742, 702 cm−1; H
NMR (400 MHz, CDCl3) δ 7.88 (s, 1H), 7.33−7.26 (m, 6H), 7.21−
7.16 (m, 3H), 7.03 (t, J = 7.2 Hz, 1H), 6.94 (dd, J = 8.0, 1.2 Hz, 1H),
6.65 (d, J = 8.2 Hz, 1H), 6.53 (s, 1H), 5.57 (s, 1H), 3.93 (br s, 2H);
13C NMR (100 MHz, CDCl3) δ 144.0, 141.1, 136.7, 135.2, 129.6,
4-Chloro-2-((4-methoxyphenyl)(naphthalen-2-yl)methyl)-
aniline (6o). 0.125 g, 67% yield; Rf = 0.37 (20:80 = EtOAc/hexane);
yellowish oil; FT-IR (neat) 3448, 3371, 3054, 2931, 2835, 2366, 1621,
1610, 1508, 1488, 1412, 1301, 1248, 1178, 1143, 1109, 1033, 961, 909,
128.9, 128.4, 128.3, 126.9, 126.3, 124.1, 122.1, 119.9, 119.8, 119.4,
119.3, 115.9, 111.1, 47.8; HR-MS (ESI, m/z) [M + H]+ calculated for
C21H18ClN2 333.1159, found 333.1141.
4-((1H-Indol-3-yl)(4-methoxyphenyl)methyl)-2-chloroaniline
(6i). 0.148 g, 82% yield; Rf = 0.30 (20:80 = EtOAc/hexane); reddish
brown solid; mp 67−69 °C; FT-IR (neat) 3416, 3380, 1619, 1508,
1
818, 780 cm−1; H NMR (400 MHz, CDCl3) δ 7.83−7.80 (m, 1H),
7.78 (d, J = 8.8 Hz, 1H), 7.72−7.70 (m, 1H), 7.46−7.44 (m, 3H), 7.27
(dd, J = 8.4, 1.6 Hz, 1H), 7.06 (d, J = 8.8 Hz, 3H), 6.86 (d, J = 8.8 Hz,
2H), 6.66 (d, J = 2.4 Hz, 1H), 6.63 (d, J = 8.4 Hz, 1H), 5.53 (s, 1H),
3.80 (s, 3H), 3.55 (br s, 2H); 13C NMR (100 MHz, CDCl3) δ 158.5,
142.6, 139.5, 133.49, 133.43, 132.4, 131.1, 130.5, 129.7, 128.4, 127.9,
127.8, 127.65, 127.60, 127.4, 126.2, 125.9, 123.7, 117.5, 114.1, 55.2,
51.4; HRMS (ESI, m/z) [M + H]+ calculated for C24H21ClNO
374.1312, found 374.1290.
1
1245, 1032, 742 cm−1; H NMR (400 MHz, CDCl3) δ 7.91 (s, 1H),
7.29 (dd, J = 11.2, 8.2 Hz, 2H), 7.20 (d, J = 8.0 Hz, 1H), 7.15 (d, J =
8.8 Hz, 3H), 7.03 (t, J = 7.2 Hz, 1H), 6.94 (dd, J = 8.2, 1.8 Hz, 1H),
6.85 (d, J = 8.6 Hz, 2H), 6.65 (d, J = 8.4 Hz, 1H), 6.52 (d, J = 1.3 Hz,
1H), 5.52 (s, 1H), 3.93 (br s, 2H), 3.80 (s, 3H); 13C NMR (100 MHz,
CDCl3) δ 158.0, 141.0, 136.7, 136.2, 135.6, 129.8, 129.5, 128.2, 126.9,
123.9, 122.1, 120.1, 119.9, 119.3, 119.2, 115.9, 113.7, 111.1, 55.2, 46.9;
HR-MS (ESI, m/z) [M + H]+ calculated for C22H20ClN2O 363.1264,
found 363.1260.
2-Chloro-4-((4-methoxyphenyl)(phenyl)methyl)aniline (6j).
0.098 g, 61% yield; Rf = 0.2 (10:90 = EtOAc/n-hexane); yellow
liquid; FT-IR (neat) 3472, 3379, 1621, 1507, 1247, 1032, 701 cm−1;
1H NMR (400 MHz, CDCl3) δ 7.40−7.30 (t, J = 7.2 Hz, 2H), 7.29−
4-Methoxy-2-(1-(4-methoxyphenyl)ethyl)aniline (6p).4c−f
0.081 g, 63% yield; Rf = 0.21 (20:80 = EtOAc/hexane); dark brown
semi solid; FT-IR (neat) 3514, 3411, 3083, 3029, 1635, 1598, 1492,
1462, 1325, 1281, 1244, 1174, 1112, 1078, 1030, 973, 890, 743 cm−1;
1H NMR (400 MHz, CDCl3) δ 7.11 (d, J = 8.4 Hz, 2H), 6.86 (d, J =
2.8 Hz, 1H), 6.79 (d, J = 8.8 Hz, 2H), 6.73−6.69 (1H), 6.65 (dd, J =
2940
dx.doi.org/10.1021/jo4028598 | J. Org. Chem. 2014, 79, 2934−2943

The Journal of Organic Chemistry
Article
8.4, 2.8 Hz, 1H), 4.10 (q, J = 7.2 Hz, 1H), 3.99−3.22 (broad, 2H),
3.76 (s, 3H), 3.75 (s, 3H), 1.56 (d, J = 7.2 Hz, 3H); 13C NMR (100
MHz, CDCl3) δ 158.1, 153.8, 137.1, 135.8, 133.4, 128.4, 118.1, 114.17,
114.11, 111.5, 55.6, 55.2, 39.3, 21.9; HRMS (ESI, m/z) [M + H]+
calculated for C16H20NO2 258.1494, found 258.1474.
109.9, 83.5, 33.9, 27.9; HRMS (ESI, m/z) [M + H]+ calculated for
C16H20ClN2O2 307.1213, found 307.1205.
2-Chloro-4-(2-methoxybenzyl)aniline (6w). 0.051 g, 41% yield;
Rf = 0.25 (10:90 = EtOAc/hexane); light brown liquid; FT-IR (neat)
3504, 3421, 3081, 3028, 1635, 1588, 1492, 1462, 1366, 1281, 1244,
1
2-Chloro-4-(1-(thiophen-2-yl)ethyl)aniline (6q). 0.104 g, 88%
yield; Rf = 0.37 (10:90 = EtOAc/hexane); light yellow liquid; FT-IR
(neat) 3464, 3379, 2967, 2932, 2878, 1888, 1620, 1504, 1454, 1415,
1174, 1155, 1072, 1040, 973, 852, 743 cm−1; H NMR (400 MHz,
CDCl3) δ 7.18 (td, J = 8.0, 1.6 Hz, 1H), 7.09 (d, J = 1.6 Hz, 1H), 7.04
(d, J = 7.2 Hz, 1H), 6.90 (dd, J = 8.4, 1.6 Hz, 1H), 6.85 (dd, J = 7.6,
2.4 Hz, 2H), 6.66 (d, J = 8.0 Hz, 1H), 3.89 (br s, 2H), 3.83 (s, 2H),
3.80 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 157.2, 140.7, 132.0,
130.1, 129.69, 129.63, 128.2, 127.4, 120.5, 119.2, 115.8, 110.4, 55.3,
34.7; HRMS (ESI, m/z) [M + H]+ calculated for C14H15ClNO:
248.0842, found 248.0853.
1
1312, 1281, 1230, 1152, 1045, 870, 822 cm−1; H NMR (400 MHz,
CDCl3) δ 7.18 (d, J = 1.6 Hz, 1H), 7.16 (dd, J = 5.2, 0.8 Hz, 1H), 6.98
(dd, J = 8.4, 2.0 Hz, 1H), 6.94 (dd, J = 5.2, 3.6 Hz, 1H), 6.81 (d, J =
3.2 Hz, 1H), 6.71 (d, J = 8.4 Hz, 1H), 4.24 (q, J = 7.1 Hz, 1H), 4.01
(br s, 2H), 1.67 (d, J = 7.2 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ
150.8, 141.3, 137.2, 128.1, 126.65, 126.62, 123.6, 123.5, 119.3, 116.0,
39.7, 23.4; HRMS (ESI, m/z) [M + H]+ calculated for C12H13ClNS
238.0457, found 238.0471.
2-Chloro-4-(4-methoxybenzyl)aniline (6x). 0.081 g, 65% yield;
Rf = 0.31 (10:90 = EtOAc/hexane); light brown liquid; FT-IR (neat)
3504, 3411, 3081, 3028, 1635, 1598, 1492, 1462, 1325, 1281, 1244,
1
1174, 1112, 1072, 1030, 973, 852, 743 cm−1; H NMR (400 MHz,
2-Chloro-4-(2-methyl-1-(thiophen-2-yl)propyl)aniline (6r).
0.070 g, 53% yield; Rf = 0.40 (05:95 = EtOAc/hexane); brown liquid;
FT-IR (neat) 3475, 3384, 3028, 2958, 2928, 2870, 2365, 1622, 1505,
1467, 1418, 1386, 1367, 1310, 1282, 1196, 1159, 1045, 948, 882, 853,
CDCl3) δ 7.09−7.05 (m, 3H), 6.87 (dd, J = 8.0, 1.6 Hz, 1H), 6.83 (d, J
= 8.8 Hz, 2H), 6.68 (d, J = 8.4 Hz, 1H), 3.82 (br s, 2H), 3.79 (s, 2H),
3.78 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 158.0, 140.9, 133.3,
132.6, 129.7, 129.5, 128.0, 119.3, 116.0, 113.9, 55.2, 39.8; HRMS (ESI,
m/z) [M + H]+ calculated for C14H15ClNO 248.0842, found
248.0853.
1
818, 756 cm−1; H NMR (400 MHz, CDCl3) δ 7.16 (d, J = 1.6 Hz,
1H), 7.10 (d, J = 5.2 Hz, 1H), 6.99 (dd, J = 8.4, 2.0 Hz, 1H), 6.88 (dd,
J = 4.8, 3.6 Hz, 1H), 6.84 (d, J = 2.8 Hz, 1H), 6.67 (d, J = 8.0 Hz, 1H),
3.91 (s, 2H), 3.59 (d, J = 9.6 Hz, 1H), 2.32−2.23 (m, 1H), 0.93 (d, J =
6.4 Hz, 3H), 0.84 (d, J = 6.4 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ
148.9, 141.1, 135.3, 128.8, 127.2, 126.4, 123.8, 123.2, 119.1, 115.9,
54.4, 34.2, 21.8, 21.4; GC-HRMS (EI, m/z) [M]+ calculated for
C14H16ClNS 265.0692, found 265.0692.
2-Chloro-4-(1-(thiophen-2-yl)but-3-en-1-yl)aniline (6s). 0.095
g, 72% yield; Rf = 0.32 (10:90 = EtOAc/hexane); light yellow liquid;
FT-IR (neat) 3472, 3382, 3076, 2919, 2848, 1616, 1504, 1428, 1310,
1200, 1156, 1044, 989, 914, 814 cm−1; 1H NMR (400 MHz, CDCl3) δ
7.13 (dd, J = 4.0, 2.0 Hz, 2H), 6.95 (dd, J = 8.4, 2.0 Hz, 1H), 6.91 (dd,
J = 4.8, 3.2 Hz, 1H), 6.81 (d, J = 3.2 Hz, 1H), 6.69 (d, J = 8.0 Hz, 1H),
5.76−5.65 (m, 1H), 5.04 (dd, J = 17.2, 1.6 Hz, 1H), 4.98 (dd, J = 10.4,
0.8 Hz, 1H), 4.09 (t, J = 8.0 Hz, 1H), 3.95 (br s, 2H), 2.86−2.78 (m,
1H), 2.75−2.68 (m, 1H); 13C NMR (100 MHz, CDCl3) δ 148.9,
141.4, 136.1, 135.1, 128.5, 127.0, 126.5, 123.8, 123.6, 119.2, 116.8,
115.9, 45.7, 41.5; HRMS (ESI, m/z) [M + H]+ calculated for
C14H14ClNS 264.0614, found 264.0596.
2-Chloro-4-(1-(furan-2-yl)propyl)aniline (6t). 0.066 g, 56%
yield; Rf = 0.42 (10:90 = EtOAc/hexane); light yellow liquid; IR
(neat) 3475, 3385, 2964, 2931, 2874, 1623, 1505, 1458, 1419, 1310,
1147, 1046, 1010, 939, 884, 806 cm−1; 1H NMR (400 MHz, CDCl3) δ
7.30 (d, J = 0.8 Hz, 1H), 7.10 (d, J = 2.0 Hz, 1H), 6.92 (dd, J = 8.4, 2.0
Hz, 1H), 6.69 (d, J = 8.0 Hz, 1H), 6.27 (dd, J = 2.8, 2.0 Hz, 1H), 6.03
(d, J = 3.2 Hz, 1H), 3.93 (br s, 2H), 3.68 (t, J = 7.6 Hz, 1H), 2.10−
2.01 (m, 1H), 1.88−1.77 (m, 1H), 0.87 (t, J = 7.2 Hz, 3H); 13C NMR
(100 MHz, CDCl3) δ 158.0, 141.3, 141.2, 133.7, 128.6, 127.1, 119.2,
115.9, 109.9, 105.1, 46.0, 27.7, 12.3; HRMS (ESI, m/z) [M + H]+
calculated for C13H15ClNO 236.0842, found 236.0838.
(E)-2-(1,3-Diphenylallyl)-4-nitroaniline (8a). 0.129 g, 78% yield;
Rf = 0.20 (10:90 = EtOAc/hexane); yellow liquid; FT-IR (neat) 3485,
1
3387, 1626, 1490, 1302, 972 cm−1; H NMR (400 MHz, CDCl3) δ
8.15−8.00 (2H), 7.55−7.20 (10H), 6.75−6.60 (2H), 6.37 (d, J = 16
Hz, 1H), 4.85 (d, J = 7.2 Hz, 1H), 4.33 (bs, 2H); 13C NMR (100
MHz, CDCl3) δ 150.6, 140.0, 139.3, 136.5, 132.8, 129.3, 129.2, 128.6,
128.5, 127.8, 127.5, 126.7, 126.5, 125.8, 124.6, 114.9, 49.6; HRMS
(ESI, m/z) [M + H]+ calculated for C21H19N2O2 331.1447, found
331.1445.
(E)-Ethyl 4-Amino-3-(1,3-diphenylallyl)benzoate (8b). 0.128
g, 71% yield; Rf = 0.30 (10:90 = EtOAc/hexane); light yellow liquid;
FT-IR (neat) 3476, 3375, 1693, 1624, 1603, 1279, 1106, 1027, 699
1
cm−1; H NMR (400 MHz, CDCl3) δ 7.95−7.75 (2H), 7.55−7.15
(10H), 6.85−6.70 (2H), 6.36 (d, J = 16 Hz, 1H), 4.87 (d, J = 7.2 Hz,
1H), 4.33 (q, J = 6.8 Hz, 2H), 3.97 (bs, 2H), 1.37 (t, J = 7.2 Hz, 3H);
13C NMR (100 MHz, CDCl3) δ 166.9, 148.7, 141.1, 137.0, 132.0,
131.5, 131.3, 130.4, 129.8, 128.9, 128.6, 128.5, 127.5, 127.1, 126.7,
126.4, 120.3, 115.3, 113.7, 60.4, 49.8, 14.4; LRMS (ESI, m/z) [M +
H]+ calculated for C24H24NO2 358.1807, found 358.1832.
(E)-4-Amino-3-(1,3-diphenylallyl)benzonitrile (8c).13a 0.111 g,
65% yield; Rf = 0.37 (20:80 = EtOAc/hexane); light yellow liquid; FT-
IR (neat) 3480, 3377, 3060, 3028, 2217, 1733, 1626, 1602, 1504, 1450,
1
1424, 1307, 1266, 1210, 1161, 1030, 973, 745, 699 cm−1; H NMR
(400 MHz, CDCl3) δ 7.37−7.29 (9H), 7.26−7.20 (3H), 6.65 (d, J =
8.4 Hz, 1H), 6.58 (dd, J = 16.0, 7.2 Hz, 1H), 6.29 (d, J = 16.0 Hz, 1H),
4.79 (d, J = 6.8 Hz, 1H), 4.07 (br s, 2H); 13C NMR (100 MHz,
CDCl3) δ 148.5, 140.2, 136.5, 133.4, 132.6, 132.0, 129.5, 129.1,
128.68, 128.66, 127.8, 127.7, 127.4, 126.4, 120.3, 115.8, 100.6, 49.2;
HRMS (ESI, m/z) [M + H]+ calculated for C22H19N2 311.1548, found
311.1524.
4-Methoxy-2-(thiophen-2-ylmethyl)aniline (6u). 0.066 g, 60%
yield; Rf = 0.34 (20:80 = EtOAc/hexane); brown solid; mp 50−55 °C;
FT-IR (neat) 3445, 3369, 3001, 2959, 2931, 2836, 1621, 1583, 1509,
(E)-2-(1,3-Diphenylallyl)-4-(trifluoromethyl)aniline (8d).13a
0.120 g, 68% yield; Rf = 0.3 (10:90 = EtOAc/hexane); light yellow
liquid; FT-IR (neat) 3476, 3391, 2925, 1627, 1328, 1111, 746, 699
1
1488, 1440, 1413, 1248, 1178, 1142, 1033, 907, 838, 762 cm−1; H
NMR (400 MHz, CDCl3) δ 7.15 (dd, J = 5.2, 0.8 Hz, 1H), 6.91 (dd, J
= 5.2, 3.6 Hz, 1H), 6.80 (dd, J = 3.2, 0.8 Hz, 1H), 6.72 (1H), 6.68 (d, J
= 2.8 Hz, 1H), 6.64(1H), 4.04 (s, 2H), 3.74 (s, 3H), 3.20 (br s, 2H);
13C NMR (100 MHz, CDCl3) δ 153.0, 142.6, 137.9, 126.9, 126.6,
1
cm−1; H NMR (400 MHz, CDCl3) δ 7.54−7.22 (12H), 6.80−6.66
(2H), 6.39 (dd, J = 0.8 Hz and 16 Hz, 1H), 4.92 (d, J = 6.8 Hz, 1H),
3.89 (s, 2H); 13C NMR (100 MHz, CDCl3) δ 147.4, 140.8, 136.8,
132.3, 130.1, 129.0, 128.7, 128.6, 127.7, 127.4, 127.2, 126.5, 126.3 (q, J
= 3.7 Hz), 125.0 (q, J = 3.7 Hz), 120.3 (q, J = 32.2 Hz), 115.7, 49.7;
HRMS (ESI, m/z) [M + H]+ calculated for C22H19F3N 354.1470,
found 354.1495.
125.1, 124.2, 117.4, 116.2, 113.2, 55.7, 32.7; HRMS (ESI, m/z) [M +
H]+ calculated for C12H14NOS 220.0796, found 220.0791.
tert-Butyl 2-(4-Amino-3-chlorobenzyl)-1H-pyrrole-1-carbox-
ylate (6v). 0.089 g, 58% yield; Rf = 0.35 (10:90 = EtOAc/hexane);
clear liquid; FT-IR (neat) 3474, 3381, 2980, 2932, 1738, 1624, 1505,
1457, 1406, 1370, 1324, 1258, 1234, 1159, 1123, 1061, 1013, 931, 893,
(E)-2-(1,3-Diphenylallyl)-4-fluoroaniline (8e).13a 0.114 g, 75%
yield; Rf = 0.30 (10:90 = EtOAc/hexane); light yellow liquid; FT-IR
(neat) 3437, 3367, 1625, 1496, 1257, 964 cm−1; 1H NMR (400 MHz,
CDCl3) δ 7.40−7.15 (10H), 6.85−6.65 (2H), 6.63−6.50 (2H), 6.26
(dd, J = 0.8 and 16 Hz, 1H), 4.84 (d, J = 6.8 Hz, 1H), 3.39 (bs, 2H);
13C NMR (100 MHz, CDCl3) δ 157.8 and 155.4 (d, J = 235 Hz),
141.1, 140.3, 140.2, 136.9, 132.0, 130.6, 130.0, and 129.9 (d, J = 6.3
1
847 cm−1; H NMR (400 MHz, CDCl3) δ 7.22 (dd, J = 3.2, 2.0 Hz,
1H), 7.06 (d, J = 1.6 Hz, 1H), 6.87 (dd, J = 8.0, 1.6 Hz, 1H), 6.68 (d, J
= 8.4 Hz, 1H), 6.06 (t, J = 3.6 Hz, 1H), 5.76 (d, J = 0.8 Hz, 1H), 4.07
(s, 2H), 3.93 (br s, 2H), 1.52 (s, 9H); 13C NMR (100 MHz, CDCl3) δ
149.4, 140.9, 134.5, 130.7, 129.5, 128.1, 121.3, 119.1, 115.8, 112.9,
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Hz), 128.9, 128.8, 128.6, 127.6, 127.1, 126.4, 117.3, and 117.2 (d, J =
7.6 Hz), 115.9 and 115.7 (d, J = 23.2 Hz), 114.0 and 113.8 (d, J = 22.1
Hz), 49.4; HR-MS (ESI, m/z) [M + H]+ calculated for C21H19NF
304.1496, found 304.1486.
ASSOCIATED CONTENT
* Supporting Information
Spectroscopic data for all new compounds. This material is
available free of charge via the Internet at http://pubs.acs.org.
■
S
(E)-2-(1,3-Diphenylallyl)-4-methylaniline (8f).13a 0.109 g, 73%
yield; Rf = 0.2 (2:98 = EtOAc/hexane); orange liquid; FT-IR (neat)
AUTHOR INFORMATION
Corresponding Author
*E-mail: pghorai@iiserb.ac.in.
1
3436, 3362, 3025, 1623, 1503, 1449, 1281, 972 cm−1; H NMR (400
■
MHz, CDCl3) δ 7.58−7.12 (10H), 6.99 (s, 2H), 6.76 (dd, J = 7.2 and
16 Hz, 1H), 6.67 (d, J = 8.4 Hz, 1H), 6.36 (d, J = 16 Hz, 1H), 4.95 (d,
J = 7.2 Hz, 1H), 3.48 (bs, 2H), 2.31 (s, 3H), ; 13C NMR (100 MHz,
CDCl3) δ 141.9, 141.7, 137.2, 131.6, 131.4, 129.8, 128.8, 128.7, 128.6,
128.3, 128.2, 128.1, 127.4, 126.8, 126.4, 116.7, 49.6, 20.7; HR-MS
(ESI, m/z) [M + H]+ calculated for C22H22N 300.1752, found
300.1764.
Author Contributions
‡These authors contributed equally to this work.
Notes
The authors declare no competing financial interest.
2-(1,3-Diphenylprop-2-yn-1-yl)-4-methylaniline (8g). 0.107 g,
72% yield; Rf = 0.34 (10:90 = EtOAc/hexane); dark brown liquid; FT-
IR (neat) 3436, 3367, 3025, 2922, 2857, 1624, 1601, 1505, 1491, 1449,
ACKNOWLEDGMENTS
■
This work has been funded by Department of Science &
Technology (DST), New Delhi and IISER Bhopal. R.N. and
M.R. thank CSIR, New Delhi for doctoral fellowship. We are
thankful to Dr. Deepak Chopra, Assist. Prof., IISER Bhopal for
useful discussions.
1
1279, 1155, 1071, 1029, 915, 815, 756, 730 cm−1; H NMR (400
MHz, CDCl3) δ 7.44 (d, J = 7.2 Hz, 4H), 7.35−7.31 (m,2H), 7.29−
7.26 (m,4H), 7.08 (s, 1H), 6.93 (dd, J = 8.0, 1.6 Hz, 1H), 6.62 (d, J =
8.0 Hz, 1H), 5.23 (s, 1H), 3.48 (br s, 2H), 2.25 (s, 3H); 13C NMR
(101 MHz, CDCl3) δ 141.4, 139.6, 131.7, 130.1, 128.8, 128.7, 128.3,
128.2, 128.0, 127.9, 127.1, 125.8, 123.3, 117.1, 88.9, 85.1, 40.1, 20.6;
HRMS (ESI, m/z) [M + H]+ calculated for C24H24N 326.1909, found
326.1922.
REFERENCES
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