De novo synthesis of functionalized 1,3-enynes and extended conjugated molecular systems

Article abstract of DOI:10.1039/c5ra01544h

Pd-catalyzed coupling of 1,3-dienyldibromides with triarylbismuths was demonstrated for the synthesis of a diverse range of 1,3-enynes. This study provided easy access to a range of functionalized 1,3-enynes in high yields utilizing triarylbismuths in sub

Full text of DOI:10.1039/c5ra01544h

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De novo synthesis of functionalized 1,3-enynes and
extended conjugated molecular systems†
Cite this: RSC Adv., 2015, 5, 24834
*
Maddali L. N. Rao, Priyabrata Dasgupta and Venneti N. Murty
Pd-catalyzed coupling of 1,3-dienyldibromides with triarylbismuths was demonstrated for the synthesis of a
diverse range of 1,3-enynes. This study provided easy access to a range of functionalized 1,3-enynes in high
yields utilizing triarylbismuths in sub-stoichiometric amounts. A new and concise route was unveiled for the
synthesis of extended p-conjugated molecular systems with the help of chemoselective couplings and in
conjunction with Sonogashira, Heck and arylation reactions under combined catalysis.
Received 26th January 2015
Accepted 26th February 2015
DOI: 10.1039/c5ra01544h
www.rsc.org/advances
(Table 1). It was explored with Pd(PPh3)4 in DMF and different
bases (entries 1–4, Table 1). Interestingly, an effective tandem
Introduction
coupling was obtained using Cs2CO3 and 2 h conditions with
the formation of 1,3-enyne 2a in 70% yield (entry 3, Table 1).
Encouragingly, this yield was further improved to 84% in 3 h
duration (entry 4, Table 1). Further investigation using
PdCl2(PPh3)2 and Pd2(dba)3/2 PPh3 catalysts gave 61% and 79%
yields (entries 5 and 6, Table 1). Whereas, couplings with
Pd(PPh3)4 in N-methyl-2-pyrrolidone (NMP) and N,N-dimethyl-
acetamide (DMA) furnished moderate yields (entries 7 and 8,
Table 1). Other screenings with lowering base (entry 9, Table 1)
or catalyst amount and different heating conditions furnished
lowered yields (entries 10–13, Table 1). Importantly, formation
of 1-bromoenyne was observed when the reaction was run
without catalyst (entry 14, Table 1). This screening thus helped
us to realize an efficient protocol using Pd(PPh3)4 and Cs2CO3 in
DMF to achieve the desired tandem coupling in high product
yield (entry 4, Table 1).
Efforts towards the synthesis of conjugated molecular skeletons
are in high demand1,2 and these systems with extended conju-
gation have been targets for medicinal, optical and electronic
applications.3,4 Importantly, 1,3-dienyldibromide as a molecular
synthon was addressed very sparingly and an elaborate struc-
tural reactivity is conspicuously missing. There is a desperate
need for an elaborate study of these reagents with broader
applicability and selectivity (Scheme 1).5 Prudently, the impact
of pot-economic process6 is enormous as this approach greatly
reduces the chemical waste during the reaction process. This
prompted us to explore for the synthesis of functionalized
(E)-1,3-enynes under pot-economic tandem process.
Importantly, 1,1-dibromides are serving as novel synthons in
organic synthesis.7 In the present context, 1,3-dienyldibromides
can be easily prepared from cinnamaldehydes through Ramirez
olenation.8 Accordingly, several 1,3-dienyldibromides (1a–1m)
have been prepared (Scheme 1) for our coupling study towards
1,3-enynes using triarylbismuth reagents. Application of triaryl-
bismuths as organometallic nucleophiles offer advantages such
as atom-economic threefold reactivity and faster cross-coupling
protocols under metal catalyzed conditions.9,10 Our envisioned
approach is given in Scheme 1 which involves initial tandem
synthesis of 1,3-enynes followed by pot-economic in situ func-
tionalizations for the synthesis of extended conjugated molec-
ular systems under palladium-catalyzed conditions.
An elaborate structural reactivity with various functionalized
dibromides has been explored in couplings with triarylbismuth
Results and discussion
To achieve this goal, our initial screening was explored with
1a and tri(p-tolyl)Bi under palladium coupling conditions
Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016,
India. E-mail: maddali@iitk.ac.in; Fax: +91 512 259 7532; Tel: +91 512 259 7532
† Electronic supplementary information (ESI) available: Full experimental details
with 1H,13
C NMR spectra and mass spectra for all compounds. See DOI:
Scheme 1 Our approach towards conjugated systems.
10.1039/c5ra01544h
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Table 1 Optimizationa,b,c
Table 2 Tandem synthesis of 1,3-enynesa,b,c
Entry
Catalyst
Base
Solvent
Time (h)
2a (%)
1
2
3
4
5
6
7
8
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
PdCl2(PPh3)2
Pd2(dba)3/2 PPh3
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
—
K3PO4
K2CO3
DMF
DMF
DMF
DMF
DMF
DMF
NMP
DMA
DMF
DMF
DMF
DMF
DMF
DMF
2
2
2
3
3
3
3
3
3
4
3
3
3
3
55
50
70
84
61
79
58
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
56
9
54d
79
10
11
12
13
14
75e
49f
34g,h
0i
a
Conditions: 1a (0.375 mmol, 3 equiv.), Bi(p-tolyl)3 (0.125 mmol,
1 equiv.), Pd catalyst (0.0112 mmol, 0.09 equiv.), base (1.125 mmol,
b
c
9 equiv.), solvent (6 mL), 80 ꢀC. Isolated yields. Biaryls as side
d
e
products formed in minor amounts. With 6 equiv. of base. With
5 mol% catalyst. f At 90 ꢀC. g At 60 ꢀC. h GC conversion. i 1-Bromoenyne
formed.
reagents (Table 2). This reactivity of different dibromides
(1a–1e) in general afforded good to excellent yields. In fact, our
tandem protocol was proved to be useful for the synthesis of a
library of enynes in good to high yields.
While the electron-rich dibromides (1b–1e) reacted fairly
well to give different enynes (3–6) in 61–85% yields, the corre-
sponding reactivity with electron-decient dibromide 1f was
proved to be moderate with the formation of 7a in 56% yield.
The reactivity of chloro substituted dibromides 1g and 1h was
appreciable to give enynes (8a–8h, 9a) in 65–77% yields. The
couplings of furanyl and thienyl derived dibromides 1i and 1j
furnished a group of heteroaryl substituted enynes (10 and 11)
in 58–82% yields.
This study was extended towards tandem bis-couplings
using 1,3-substituted dibromide (1k). This was to explore the
possibility for the synthesis of bis-enynes (12a–12c) in one-pot
operation. This approach was proved to be synthetically
highly useful and corresponding bis-enynes were obtained in
61–70% yields. Further, chemoselective couplings were
explored under the established coupling conditions using 1l
and 1m possessing reactive aryl bromide. It is to be highlighted
that this led to the preparation of several bromo functionalized
enynes (13–15) in 60–82% yields. In these couplings, several aryl
and heteroaryl bismuth reagents participated effectively with
good to high yields.
a
Conditions: dibromide (0.375 mmol, 3 equiv.), BiAr3 (0.125 mmol,
1 equiv.), Pd(PPh3)4 (0.0112 mmol, 0.09 equiv.), Cs2CO3 (1.125 mmol,
b
c
9 equiv.), DMF, 80 ꢀC, 3 h. Isolated yields. Biaryls formed in minor
In recent times, consecutive or sequential reactions with
atom- or pot-economy are gaining popularity.6 With the
accomplishment of a wide spectrum of mono- and bis-
amounts. d With additional BiAr3 (0.25 mmol) and 6 h duration.
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Table 4 Functionalization with arylationa,b,c
couplings, it was of interest to establish pot-economic process
with in situ functionalizations under palladium coupling
conditions.
This was to impart the overall process with greater synthetic
utility in the preparation of compounds with extended p-conju-
gation. For this, we adopted sequential couplings involving
tandem synthesis of 1,3-enynes in step 1 followed by alkynylation
(Table 3), arylation (Table 4) or alkenylation (Table 5) in step 2 to
synthesize a wide variety of both linear and cross-conjugated
p-extended 1,3-enynes. To our delight, we could achieve this in
a versatile manner with careful adaptation of reaction conditions
for step 2. To start with, the strategy for the extension of
molecular complexity with additional alkyne was planned with
the Sonogashira coupling. In fact, the selection of a compatible
condition for step 2 was cumbersome as innumerable protocol
conditions are available for the Sonogashira reaction. However,
we could nally explore the best option and achieved the desired
extended conjugation with different alkyne functionality under
compatible in situ reaction conditions11 (Table 3).
a
Conditions for step 1: Table 2 reaction conditions followed; for step 2:
Pd(PPh3)4 (0.006 mmol, 0.048 equiv.), BiAr3 (0.125 mmol, 1 equiv.),
Cs2CO3 (0.564 mmol, 4.5 equiv.), 110 ꢀC, 4 h. Isolated yields. c Step 2
was not optimized.
b
Appreciably, under the adopted conditions using combined
catalytic approach, the nal alkynylated products (16a–16f) were
obtained with 30–59% as overall yields. This was a clear indi-
cation of the facile and amenable nature of our conditions to
This one-pot in situ functionalizations under combined
evolve a combined catalytic process for pot-economic in situ catalysis was extended to arylation of enynes using triaryl-
Sonogashira alkynylations towards 1,3-enyne systems with bismuth reagents in step 2 and was given in Table 4.12 This
extended alkyne functionality.
approach of in situ coupling of aryl bromide with different
bismuth reagents afforded arylated 1,3-enynes 17a–17c in
48–52% yields.
Encouraged by the compatibility witnessed above under
combined catalytic approach, further attempts have been made
for in situ Heck type alkenylations.13 Again, it was a challenging
scenario to come up with the right combination of conditions
for the Heck reaction as several protocols are known.
Table 3 Functionalization with Sonogashira reactiona,b,c
Table 5 Functionalization with Heck reactiona,b,c
a
a
Conditions for step 1: Table 2 reaction conditions followed; for step 2:
Conditions for step 1: Table 2 reaction conditions followed; for step 2:
Pd(PPh3)4 (0.006 mmol, 0.048 equiv.), alkyne (0.75 mmol, 6 equiv.), ethyl acrylate (0.562 mmol, 4.5 equiv.), Pd(PPh3)4 (0.006 mmol,
b
TBAB (0.75 mmol, 6 equiv.), NEt3 (1.875 mmol, 15 equiv.), DMSO, 0.048 equiv.), NEt3 (1.875 mmol, 15 equiv.), 110 ꢀC, 4 h. Isolated
b
100 ꢀC, 4 h. Isolated yields. c Step 2 was not optimized.
yields. c Step 2 was not optimized.
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Conclusions
We have demonstrated a de novo synthesis of functionalized
1,3-enynes and its extended conjugated molecular systems from
1,3-dienyldibromides under palladium-catalyzed conditions. This
one-pot tandem protocol involves the utilization of threefold
reactivity of triarylbismuths and the synthesis of an array of
functionalized (E)-1,3-enynes. The established chemoselective
couplings and additional functionalizations have been carried out
under combined catalysis to afford p-conjugated enynes with
regulated structural features, thus proving the broad scope. The
combined catalytic approach adopted with three in situ function-
alizations employing Sonogashira, Heck or arylations demon-
strates the broad applicability of the developed palladium protocol
conditions in one-pot operation. Overall, the scope of different 1,3-
dienyldibromides as masked enyne scaffolds was thoroughly
established for the rst time. This investigation thus unraveled the
depth and synthetic utility of 1,3-dienyldibromides and has the
potential to open up several new possibilities in this direction.
Scheme 2 A two-step control reaction.
Experimental
General
Scheme 3 Mechanistic cycle.
The cross-coupling reactions have been performed in dry
Schlenk tubes under nitrogen conditions. The dibromides
(1a–1m) have been prepared from cinnamaldehydes.8 General
method of preparation for different cinnamaldehydes was given
in the ESI.†14,15 Solvents have been dried according to standard
procedures. Purication of products was carried out by silica gel
column chromatography using ethyl acetate/hexane as eluent.
1H and 13C NMR spectra were recorded using JEOL ECS 400
(400 MHz) and JEOL ECX 500 (500 MHz). HRMS was recorded
using Electron Ionization (EI) and Electrospray Ionization (ESI)
techniques with Waters CAB155 GCT Premier analyzer and
Waters HAB 213 Q-TOF Premier analyzer. IR was recorded on
PerkinElmer FT-IR.
Our efforts thus led to the fruitful outcome with in
situ functionalization using ethyl acrylate in step 2 (Table 5).
The combined catalytic approach thus overall furnished
stereoselective (E)-alkenylated enynes (18a–18d) in 42–52%
yields.
This unprecedented strategy of in situ functionalization of
enynes under combined catalysis demonstrated a practicable
and straightforward approach for the synthesis of an array of
enynes with extended p-conjugation in three different ways.
These processes starting from readily accessible 1,3-dienyldi-
bromides and tailored through a complementary tandem and
consecutive catalytic couplings paid rich dividends to synthe-
size p-conjugated extended enynes in a two-step one-pot
operation.
To gain insights into the reaction mechanism a stepwise
coupling was performed as given in Scheme 2. This two-step
sequence furnished enyne 2a in 86% yield aer the second
step. GC/GC-MS analysis of the reaction mixture aer the rst
step indicated the formation of 1-bromo-1,3-enyne intermediate
1.1. This was in tune with our earlier observation as 1-bromo-
1,3-enyne was formed during the optimization study and in
the absence of palladium catalyst (entry 14, Table 1).
This refers to the initial dehydrobromination of 1,3-dienyl-
dibromide to give 1.1, which in the presence of palladium cross-
couples with bismuth reagent to give 1,3-enyne (Scheme 3). This
process was expected to go through usual steps known for cross-
coupling sequence comprising oxidative addition (1.2), trans-
metallation (1.3) and reductive elimination. The possibility of
initial cross-coupling of bismuth reagent with 1,3-dienyl-
dibromide followed by base mediated dehydrobromination
although cannot be ruled out completely at this stage.
Representative cross-coupling procedure for Table 2
The reaction was performed by charging dry Schlenk tube with
Bi(p-tolyl)3 (0.060 g, 0.125 mmol, 1 equiv.), 1a (0.108 g, 0.375
mmol, 3 equiv.), Cs2CO3 (0.367 g, 1.125 mmol, 9 equiv.),
Pd(PPh3)4 (0.013 g, 0.0112 mmol, 0.09 equiv.) and DMF (6 mL).
The contents were stirred at 80 ꢀC in an oil bath for 3 h. Aer the
completion, it was cooled to rt and extracted with ethyl acetate
(50 mL), washed with water (15 mL), brine (15 mL), dried over
anhydrous MgSO4 and concentrated. The crude product was
puried using silica gel column chromatography using ethyl
acetate/hexane as eluent. The product 2a was obtained as pale
yellow solid (0.069 g, 84%). The cross-coupled product yield
calculated considering 0.375 mmol as 100% yield.
Representative cross-coupling procedure for bis-coupling
(for Table 2, compounds 12a–12c)
The coupling procedure given above for Table 2 was followed
with conditions involving Bi(p-ethoxyphenyl)3 (0.215 g,
0.375 mmol, 1 equiv.), 1k (0.187 g, 0.375 mmol, 1 equiv.),
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Cs2CO3 (1.09 g, 3.37 mmol, 9 equiv.), Pd(PPh3)4 (0.026 g, 0.0225 6.66 (m, 2H), 2.34 (s, 3H, –CH3). 13C (125 MHz, CDCl3): d 138.7,
ꢀ
mmol, 0.06 equiv.), DMF (15 mL), 80 C, 6 h. The product 12c 137.2, 135.7, 133.5, 129.5, 126.8, 124.3, 90.5, 21.3. IR (lm):
was obtained as yellow solid (0.11 g, 70%).
3009, 1602, 1507, 1280, 965, 802 cmꢁ1. HRMS (EI) calcd for
C
11H10Br2 [M+] 299.9149; found 299.9145.
Representative procedure for Table 3
1c. Yellow solid (76%); m.p. 88–90 ꢀC, Rf ¼ 0.58 (hexane). 1H
NMR (500 MHz, CDCl3): d 8.09 (d, 1H, J ¼ 8.55 Hz, Ar-H), 7.86
(d, 1H, J ¼ 7.95 Hz, Ar-H), 7.83 (d, 1H, J ¼ 8.25 Hz, Ar-H), 7.74
(d, 1H, J ¼ 7.35 Hz, Ar-H), 7.56–7.46 (m, 4H, Ar-H), 7.27 (d, 1H,
J ¼ 9.8 Hz, ]CH), 6.90–6.85 (m, 1H, ]CH). 13C (125 MHz,
CDCl3): d 137.3, 133.7, 133.6, 132.4, 131.0, 129.0, 128.7, 127.9,
126.4, 126.0, 125.6, 123.9, 123.2, 91.7. IR (lm): 3040, 1724,
1506, 1395, 1265, 963, 812, 795, 775 cmꢁ1. HRMS (EI) calcd for
The coupling procedure given above for Table 2 was followed for
the rst step with conditions involving Bi(p-chlorophenyl)3
(0.068 g, 0.125 mmol, 1 equiv.), 1l (0.138 g, 0.375 mmol,
3 equiv.), Cs2CO3 (0.367 g, 1.125 mmol, 9 equiv.), Pd(PPh3)4
ꢀ
(0.013 g, 0.01125 mmol, 0.09 equiv.), DMF (6 mL), 80 C, 3 h.
Aer the reaction is over, contents were cooled to rt and per-
formed the second step of Sonogashira with the addition of
phenylacetylene (0.077 g, 0.75 mmol, 6 equiv.), NEt3 (0.19 g,
1.875 mmol, 15 equiv.), TBAB (0.242 g, 0.75 mmol, 6 equiv.),
Pd(PPh3)4 (0.007 g, 0.0060 mmol, 0.048 equiv.), DMSO (3 mL)
C
14H10Br2 [M+] 335.9149; found 335.9140.
1d. Colourless solid (61%); m.p. 84–86 ꢀC, Rf ¼ 0.30 (EtOAc–
hexane 1 : 99). 1H NMR (500 MHz, CDCl3): d 7.39 (d, 2H, J ¼ 8.85
Hz, Ar-H), 7.07–7.05 (m, 1H, Ar-H), 6.87 (d, 2H, J ¼ 8.85 Hz),
6.66–6.65 (m, 2H), 3.82 (s, 3H, –OCH3). 13C (125 MHz, CDCl3): d
160.0, 137.3, 135.3, 129.1, 128.2, 123.2, 114.2, 89.8, 55.3. IR
(lm): 3022, 2970, 1725, 1602, 1507, 1287, 1255, 1025, 969,
812 cmꢁ1. HRMS (EI) calcd for C11H10Br2O [M+] 315.9098; found
315.9095.
ꢀ
and stirring at 100 C for 4 h. Aer workup, product 16a was
obtained as yellow solid (0.075 g, 59%).
Representative procedure for Table 4
The coupling procedure given above for Table 2 was followed for
the rst step with conditions involving Bi(p-tolyl)3 (0.061 g,
0.125 mmol, 1 equiv.), 1m (0.138 g, 0.375 mmol, 3 equiv.),
Cs2CO3 (0.367 g, 1.125 mmol, 9 equiv.), Pdꢀ(PPh3)4 (0.013 g,
0.01125 mmol, 0.09 equiv.), DMF (6 mL), 80 C, 3 h. Aer the
reaction is over, contents were cooled to rt and performed the
second step of arylation with the addition of Bi(p-tolyl)3 (0.061 g,
0.125 mmol, 1 equiv.), Cs2CO3 (0.184 g, 0.56 mmol, 4.5 equiv.),
Pd(PPh3)4 (0.007 g, 0.006 mmol, 0.048 equiv.) and stirring at
110 ꢀC for 4 h. Aer workup, product 17b was obtained as pale
yellow solid (0.059 g, 51%).
1e. Colourless solid (71%); m.p. 48–50 ꢀC, Rf ¼ 0.18 (EtOAc–
hexane 1 : 99). 1H NMR (500 MHz, CDCl3): d 7.07 (d, 1H, J ¼ 8.3
Hz, Ar-H), 6.66–6.64 (m, 4H), 3.89 (s, 6H, –OCH3), 3.86 (s, 3H,
–OCH3). 13C (125 MHz, CDCl3): d 153.4, 138.7, 136.9, 135.6,
131.9, 124.6, 103.9, 91.0, 60.9, 56.1. IR (lm): 2999, 2938, 1580,
1505, 1454, 1339, 1243, 1127, 1006, 961, 813 cmꢁ1. HRMS (EI)
calcd for C13H14Br2O3 [M+] 375.9310; found 375.9319.
1f. Colourless solid (90%); m.p. 126–128 ꢀC, Rf ¼ 0.37
(EtOAc–hexane 1 : 99). 1H NMR (500 MHz, CDCl3): d 7.62 (d, 2H,
J ¼ 8.55 Hz, Ar-H), 7.52 (d, 2H, J ¼ 8.25 Hz, Ar-H), 7.12 (d, 1H, J ¼
10.35 Hz, ]CH), 6.91–6.85 (m, 1H, Ar-H), 6.70 (d, 1H, J ¼ 15.85
Hz, ]CH). 13C (125 MHz, CDCl3): d 140.7, 136.4, 133.3, 132.5,
Representative procedure for Table 5
The coupling procedure given above for Table 2 was followed for 128.5, 127.2, 118.8, 111.5, 94.5. IR (lm): 3048, 2222, 1721, 1601,
the rst step with conditions involving Bi(p-methoxyphenyl)3 1501, 1412, 971, 809 cmꢁ1. HRMS (EI) calcd for C11H7Br2N [M+]
(0.066 g, 0.125 mmol, 1 equiv.), 1l (0.138 g, 0.375 mmol, 310.8945; found 310.8943.
3 equiv.), Cs2CO3 (0.367 g, 1.125 mmol, 9 equiv.), Pd(PPh3)4
1g. Colourless solid (69%); m.p. 72–74 ꢀC, Rf ¼ 0.77 (hexane).
(0.013 g, 0.01125 mmol, 0.09 equiv.), DMF (6 mL), 80 C, 3 h. 1H NMR (500 MHz, CDCl3): d 7.38 (d, 2H, J ¼ 8.55 Hz, Ar-H), 7.30
Aer the reaction is over, contents were cooled to rt and per- (d, 2H, J ¼ 8.55 Hz, Ar-H), 7.08 (d, 1H, J ¼ 9.75 Hz, ]CH), 6.78–
formed the second step of alkenylation with the addition of 6.73 (m, 1H, ]CH), 6.65 (d, 1H, J ¼ 15.9 Hz, ]CH). 13C (125
ethyl acrylate (0.057 g, 0.562 mmol, 4.5 equiv.), NEt3 (0.19 g, MHz, CDCl3): d 136.8, 134.8, 134.2, 129.0, 127.9, 125.7, 92.0. IR
1.875 mmol, 15 equiv.) and Pd(PPh3)4 (0.007 g, 0.006 mmol, (lm): 3013, 1725, 1491, 1406, 1097, 968, 806 cmꢁ1. HRMS (EI)
0.048 equiv.) and stirring at 110 ꢀC for 4 h. Aer workup, calcd for C10H7Br2Cl [M+] 319.8603; found 319.8600.
ꢀ
product 18c was obtained as bright yellow solid (0.06 g, 48%).
1h. Yellow liquid (79%); Rf ¼ 0.74 (hexane). 1H NMR
The analytical data for dibromides 1a–1m and for all cross- (500 MHz, CDCl3): d 7.42 (s, 1H, Ar-H), 7.32–7.25 (m, 3H, Ar-H),
coupled products is given below.
7.08 (d, 1H, J ¼ 10.4 Hz, ]CH), 6.82–6.75 (m, 1H, ]CH), 6.63 (d,
1a.16 Pale yellow solid (74%); m.p. 48–50 ꢀC, Rf ¼ 0.70 1H, J ¼ 15.6 Hz, ]CH). 13C (125 MHz, CDCl3): d 138.1, 136.7,
(hexane). 1H NMR (500 MHz, CDCl3): d 7.45 (d, 2H, J ¼ 7.95 Hz, 134.8, 134.0, 130.0, 128.4, 126.6, 126.5, 125.0, 92.6. IR (lm):
Ar-H), 7.38–7.29 (m, 3H), 7.10 (d, 1H, J ¼ 9.8 Hz, ]CH), 6.82– 3063, 1703, 1595, 1476, 1281, 1079, 963, 811, 785 cmꢁ1. HRMS
6.76 (m, 1H, ]CH), 6.71 (d, 1H, J ¼ 15.6 Hz, ]CH). 13C (EI) calcd for C10H7Br2Cl [M+] 319.8603; found 319.8609.
(125 MHz, CDCl3): d 137.1, 136.3, 135.7, 128.8, 128.6, 126.8,
1i.17 Deep brown low melting solid (76%); Rf ¼ 0.70 (hexane).
125.2, 91.3. IR (lm): 3038, 1700, 1560, 1488, 1448, 1284, 963, 1H NMR (500 MHz, CDCl3): d 7.43 (s, 1H, Ar-H), 7.02 (d, 1H, J ¼
853, 808, 747, 690 cmꢁ1. HRMS (EI) calcd for C10H8Br2 [M+] 10.3 Hz, ]CH), 6.70–6.64 (m, 1H, ]CH), 6.48 (d, 1H, J ¼ 15.45
285.8993; found 285.8994.
Hz, ]CH), 6.42–6.40 (m, 2H). 13C (125 MHz, CDCl3): d 152.3,
1b. Colourless solid (76%); m.p. 90–92 ꢀC, Rf ¼ 0.73 (hexane). 143.2, 136.7, 123.6, 122.5, 111.9, 110.7, 91.3. IR (lm): 3116,
1H NMR (500 MHz, CDCl3): d 7.35 (d, 2H, J ¼ 7.95 Hz, Ar-H), 7.15 1622, 1540, 1475, 1262, 1152, 1014, 956, 819, 738 cmꢁ1. HRMS
(d, 2H, J ¼ 7.65 Hz, Ar-H), 7.08 (d, 1H, J ¼ 9.45 Hz, ]CH), 6.77– (EI) calcd for C8H6Br2O [M+] 275.8785; found 275.8783.
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892, 788, 751 cmꢁ1. HRMS (EI) calcd for C16H11Cl [M+] 238.0549;
found 238.0549.
1j. Brown solid (71%); m.p. 56–58 ꢀC, Rf ¼ 0.69 (hexane). 1H
NMR (500 MHz, CDCl3): d 7.26 (d, 1H, J ¼ 4.6 Hz, Ar-H), 7.07
(d, 1H, J ¼ 3.45 Hz, Ar-H), 7.03–6.97 (m, 2H), 6.83 (d, 1H, J ¼
15.45 Hz, ]CH), 6.59–6.54 (m, 1H, ]CH). 13C (125 MHz,
CDCl3): d 141.6, 136.6, 128.3, 127.8, 127.5, 125.9, 124.6, 90.9. IR
(lm): 3086, 3028, 1797, 1602, 1423, 1292, 1204, 958, 818, 705
cmꢁ1. HRMS (EI) calcd for C8H6Br2S [M+] 291.8557; found
291.8552.
2d. Yellow liquid (0.064 g, 73%); Rf ¼ 0.26 (hexane). 1H NMR
(500 MHz, CDCl3): d 7.42 (d, 2H, J ¼ 7.35 Hz, Ar-H), 7.34 (t, 2H,
J ¼ 7.65 Hz, Ar-H), 7.30–7.22 (m, 2H, Ar-H), 7.08–7.01 (m, 3H, Ar-
H), 6.89–6.86 (m, 1H, Ar-H), 6.38 (d, 1H, J ¼ 16.15 Hz), 3.81
(s, 3H, –OCH3). 13C (125 MHz, CDCl3): d 159.3, 141.4, 136.3,
129.4, 128.7, 128.6, 126.3, 124.4, 124.1, 116.2, 114.9, 108.0, 91.6,
88.7, 55.3. IR (lm): 3060, 2937, 2193, 1595, 1488, 1319, 1289,
1215, 1081, 953, 779, 749, 688 cmꢁ1. HRMS (EI) calcd for
1k. Colourless solid (67%); m.p. 116–118 ꢀC, Rf ¼ 0.52
1
(hexane). H NMR (500 MHz, CDCl3): d 7.45 (s, 1H, Ar-H), 7.40
C
17H14O [M+] 234.1045; found 234.1048.
(d, 2H, J ¼ 7.6 Hz, Ar-H), 7.33–7.30 (m, 1H, Ar-H), 7.10 (d, 2H, J ¼
9.8 Hz, ]CH), 6.82–6.77 (m, 2H, ]CH), 6.71 (d, 2H, J ¼ 15.55
Hz, ]CH). 13C (125 MHz, CDCl3): d 136.9, 136.8, 135.1, 129.2,
126.7, 125.8, 125.6, 91.9. IR (lm): 3015, 2922, 1618, 1557, 1228,
969, 811, 771 cmꢁ1. HRMS (EI) calcd for C14H10Br4 [M+]
493.7516; found 493.7517.
3a.19 Yellow solid (0.060 g, 74%); m.p. 72–74 ꢀC, Rf ¼ 0.48
(hexane). 1H NMR (500 MHz, CDCl3): d 7.50–7.48 (m, 2H, Ar-H),
7.36–7.33 (m, 5H, Ar-H), 7.17 (d, 2H, J ¼ 7.95 Hz, Ar-H), 7.04
(d, 1H, J ¼ 16.2 Hz), 6.35 (d, 1H, J ¼ 16.2 Hz), 2.37 (s, 3H, –CH3).
13C (125 MHz, CDCl3): d 141.2, 138.7, 133.5, 131.4, 129.4, 128.3,
128.0, 126.2, 123.5, 106.9, 91.3, 89.1, 21.3. IR (lm): 3030, 2937,
1488, 1441, 959, 804, 754, 690 cmꢁ1. HRMS (EI) calcd for C17H14
[M+] 218.1096; found 218.1092.
1l. Colourless solid (81%); m.p. 90–92 ꢀC, Rf ¼ 0.72 (hexane).
1H NMR (500 MHz, CDCl3): d 7.46 (d, 2H, J ¼ 7.95 Hz, Ar-H), 7.31
(d, 2H, J ¼ 7.95 Hz, Ar-H), 7.08 (d, 1H, J ¼ 10.4 Hz, ]CH), 6.79–
6.74 (m, 1H, ]CH), 6.64 (d, 1H, J ¼ 15.9 Hz, ]CH). 13C
(125 MHz, CDCl3): d 136.8, 135.2, 134.2, 131.9, 128.2, 125.8,
122.4, 92.1. IR (lm): 3042, 2962, 1724, 1487, 1401, 1074, 967,
803 cmꢁ1. HRMS (EI) calcd for C10H7Br3 [M+] 363.8098; found
363.8098.
3b.18 Pale yellow solid (0.068 g, 78%); m.p. 146–148 ꢀC, Rf ¼
0.41 (hexane). 1H NMR (500 MHz, CDCl3): d 7.38 (d, 2H, J ¼ 7.95
Hz, Ar-H), 7.33 (d, 2H, J ¼ 7.95 Hz, Ar-H), 7.17–7.14 (m, 4H,
Ar-H), 7.02 (d, 1H, J ¼ 16.2 Hz), 6.35 (d, 1H, J ¼ 16.2 Hz), 2.37
(s, 6H, –CH3). 13C (125 MHz, CDCl3): d 140.8, 138.6, 138.2, 133.6,
131.3, 129.4, 129.1, 126.2, 120.4, 107.1, 91.6, 88.4, 21.5, 21.3. IR
(lm): 3027, 2939, 1910, 1505, 1109, 957, 818, 802 cmꢁ1. HRMS
(EI) calcd for C18H16 [M+] 232.1252; found 232.1254.
1
1m. Deep yellow liquid (81%); Rf ¼ 0.74 (hexane). H NMR
(500 MHz, CDCl3): d 7.57 (s, 1H, Ar-H), 7.40 (d, 1H, J ¼ 7.9 Hz,
Ar-H), 7.35 (d, 1H, J ¼ 7.95 Hz, Ar-H), 7.19 (t, 1H, J ¼ 7.8 Hz, Ar-
H), 7.08 (d, 1H, J ¼ 10.1 Hz, ]CH), 6.79–6.73 (m, 1H, ]CH),
6.61 (d, 1H, J ¼ 15.55 Hz, ]CH). 13C (125 MHz, CDCl3): d 138.4,
136.7, 133.9, 131.3, 130.2, 129.5, 126.5, 125.4, 122.9, 92.7. IR
(lm): 3050, 1789, 1730, 1591, 1554, 1476, 1071, 961, 890, 811,
776 cmꢁ1. HRMS (EI) calcd for C10H7Br3 [M+] 363.8098; found
363.8090.
ꢀ
3c. Yellow solid (0.074 g, 78%); m.p. 154–156 C, Rf ¼ 0.50
(hexane). 1H NMR (500 MHz, CDCl3): d 7.39 (d, 2H, J ¼ 8.55 Hz,
Ar-H), 7.33–7.29 (m, 4H, Ar-H), 7.16 (d, 2H, J ¼ 8.25 Hz, Ar-H),
7.02 (d, 1H, J ¼ 16.15 Hz), 6.32 (d, 1H, J ¼ 16.2 Hz), 2.36
(s, 3H, –CH3). 13C (125 MHz, CDCl3): d 141.7, 138.9, 134.0, 133.4,
132.6, 129.5, 128.6, 126.3, 122.0, 106.6, 90.2, 90.1, 21.3. IR (lm):
2939, 1910, 1487, 1397, 962, 828, 804 cmꢁ1. HRMS (EI) calcd for
2a.18 Pale yellow solid (0.069 g, 84%); m.p. 96–98 ꢀC, Rf ¼ 0.41
(hexane). 1H NMR (500 MHz, CDCl3): d 7.43 (d, 2H, J ¼ 7.35 Hz,
Ar-H), 7.39–7.33 (m, 4H, Ar-H), 7.30–7.27 (m, 1H, Ar-H), 7.15 (d,
2H, J ¼ 8.25 Hz, Ar-H), 7.03 (d, 1H, J ¼ 16.15 Hz), 6.39 (d, 1H, J ¼
16.2 Hz), 2.37 (s, 3H, –CH3). 13C (125 MHz, CDCl3): d 140.8,
138.3, 136.4, 131.4, 129.1, 128.7, 128.5, 126.2, 120.3, 108.3, 91.9,
88.2, 21.5. IR (lm): 3057, 3027, 2191, 1725, 1488, 1303, 1121,
1106, 955, 817, 748, 690 cmꢁ1. HRMS (EI) calcd for C17H14 [M+]
218.1096; found 218.1098.
2b.18 Pale yellow solid (0.056 g, 68%); m.p. 86–88 ꢀC, Rf ¼ 0.47
(hexane). 1H NMR (500 MHz, CDCl3): d 7.47–7.42 (m, 4H, Ar-H),
7.37–7.34 (m, 2H, Ar-H), 7.32–7.28 (m, 1H, Ar-H), 7.06–7.01 (m,
3H), 6.37 (d, 1H, J ¼ 16.3 Hz). 13C (125 MHz, CDCl3): d 162.4 (d, J
¼ 247.98 Hz), 141.3, 136.2, 133.3 (d, J ¼ 8.33 Hz), 128.7, 128.6,
126.3, 119.5, 115.6 (d, J ¼ 21.46 Hz), 107.9, 90.6, 88.5. IR (lm):
3027, 1594, 1505, 1222, 959, 837, 750, 691 cmꢁ1. HRMS (EI)
calcd for C16H11F [M+] 222.0845; found 222.0844.
C
17H13Cl [M+] 252.0706; found 252.0701.
3d. Pale yellow solid (0.062 g, 63%); m.p. 124–126 C, Rf ¼
ꢀ
0.34 (hexane). 1H NMR (500 MHz, CDCl3): d 7.40 (d, 2H, J ¼ 8.85
Hz, Ar-H), 7.32 (d, 2H, J ¼ 7.9 Hz, Ar-H), 7.15 (d, 2H, J ¼ 7.95 Hz,
Ar-H), 6.98 (d, 1H, J ¼ 16.2 Hz), 6.85 (d, 2H, J ¼ 8.85 Hz, Ar-H),
6.33 (d, 1H, J ¼ 16.15 Hz), 4.04 (q, 2H, J ¼ 6.92 Hz, –OCH2CH3),
2.36 (s, 3H, –CH3), 1.42 (t, 3H, J ¼ 7.02 Hz, –OCH2CH3). 13C (125
MHz, CDCl3): d 158.9, 140.4, 138.5, 133.7, 132.9, 129.4, 126.1,
115.4, 114.5, 107.3, 91.5, 87.7, 63.5, 21.3, 14.7. IR (lm): 3026,
2921, 2188, 1598, 1507, 1306, 1250, 1174, 1114, 1045, 958, 839
cmꢁ1. HRMS (EI) calcd for C19H18O [M+] 262.1358; found
262.1351.
4a. Colourless solid (0.076 g, 80%); m.p. 106–108 ꢀC, Rf ¼
0.44 (hexane). 1H NMR (500 MHz, CDCl3): d 8.19 (d, 1H, J ¼ 8.55
Hz, Ar-H), 7.89–7.83 (m, 3H, Ar-H), 7.70 (d, 1H, J ¼ 7.3 Hz, Ar-H),
7.59–7.47 (m, 5H, Ar-H), 7.40–7.34 (m, 3H, Ar-H), 6.49 (d, 1H, J ¼
15.9 Hz). 13C (125 MHz, CDCl3): d 138.3, 133.7, 133.6, 131.5,
130.8, 129.0, 128.6, 128.4, 128.2, 126.4, 126.0, 125.5, 123.5,
123.4, 123.3, 110.7, 91.5, 89.1. IR (lm): 3056, 2194, 1489, 1394,
1069, 861, 755 cmꢁ1. HRMS (EI) calcd for C20H14 [M+] 254.1096;
found 254.1095.
2c. Yellow solid (0.067 g, 75%); m.p. 68–70 ꢀC, Rf ¼ 0.56
(hexane). 1H NMR (500 MHz, CDCl3): d 7.46–7.42 (m, 3H, Ar-H),
7.37–7.26 (m, 6H, Ar-H), 7.06 (d, 1H, J ¼ 16.3 Hz), 6.36 (d, 1H, J ¼
16 Hz). 13C (125 MHz, CDCl3): d 142.0, 136.1, 134.1, 131.3, 129.6,
129.5, 128.8, 128.7, 128.4, 126.4, 125.1, 107.6, 90.2, 90.0. IR
(lm): 3022, 2374, 2195, 1655, 1559, 1460, 1404, 1290, 1079, 951,
4b. Yellow solid (0.084 g, 84%); m.p. 84–86 ꢀC, Rf ¼ 0.44
(hexane). 1H NMR (500 MHz, CDCl3): d 8.19 (d, 1H, J ¼ 8.25 Hz,
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Ar-H), 7.88–7.82 (m, 3H, Ar-H), 7.69 (d, 1H, J ¼ 7.05 Hz, Ar-H), Hz, Ar-H), 7.29 (d, 2H, J ¼ 8.55 Hz, Ar-H), 6.99 (d, 1H, J ¼ 16.15
7.56–7.43 (m, 5H, Ar-H), 7.17 (d, 2H, J ¼ 8.55 Hz, Ar-H), 6.47 Hz), 6.88 (d, 2H, J ¼ 8.55 Hz, Ar-H), 6.22 (d, 1H, J ¼ 16.15 Hz),
(d, 1H, J ¼ 15.9 Hz), 2.38 (s, 3H, –CH3). 13C (125 MHz, CDCl3): d 3.82 (s, 3H, –OCH3). 13C (125 MHz, CDCl3): d 160.2, 141.3, 133.9,
138.4, 137.9, 133.8, 133.6, 131.4, 130.8, 129.1, 128.9, 128.5, 132.6, 129.0, 128.6, 127.7, 122.1, 114.2, 105.3, 90.2, 89.8, 55.3. IR
126.3, 125.9, 125.5, 123.5, 123.3, 120.2, 110.9, 91.8, 88.5, 21.5. IR (lm): 3054, 2968, 2842, 2194, 1603, 1489, 1451, 1396, 1266,
(lm): 3027, 2916, 1506, 1018, 970, 772, 733 cmꢁ1. HRMS (EI) 1177, 1093, 1032, 938, 829 cmꢁ1. HRMS (EI) calcd for C17H13ClO
calcd for C21H16 [M+] 268.1252; found 268.1251.
[M+] 268.0655; found 268.0652.
5d. Pale brown solid (0.076 g, 73%); m.p. 146–148 C, Rf ¼
ꢀ
4c. Yellow solid (0.065 g, 64%); m.p. 88–90 ꢀC, Rf ¼ 0.52
(hexane). 1H NMR (500 MHz, CDCl3): d 8.17 (d, 1H, J ¼ 8.6 Hz, 0.47 (EtOAc–hexane 1 : 99). H NMR (500 MHz, CDCl3): d 7.39
Ar-H), 7.87–7.82 (m, 3H, Ar-H), 7.68 (d, 1H, J ¼ 7.2 Hz, Ar-H), (d, 2H, J ¼ 8.85 Hz, Ar-H), 7.36 (d, 2H, J ¼ 8.95 Hz, Ar-H), 6.95
7.57–7.45 (m, 5H, Ar-H), 7.05 (t, 2H, J ¼ 8.7 Hz, Ar-H), 6.44 (d, 1H, J ¼ 16.2 Hz), 6.87 (d, 2H, J ¼ 8.55 Hz, Ar-H), 6.84 (d, 2H,
(d, 1H, J ¼ 15.9 Hz). 13C (125 MHz, CDCl3): d 162.5 (d, J ¼ 248 J ¼ 8.55 Hz, Ar-H), 6.24 (d, 1H, J ¼ 16.2 Hz), 4.04 (q, 2H, J ¼ 7.02
Hz), 138.4, 133.6, 133.4 (d, J ¼ 8.35 Hz), 130.8, 129.0, 128.6, Hz, –OCH2CH3), 3.82 (s, 3H, –OCH3), 1.42 (t, 3H, J ¼ 7.02 Hz,
126.4, 126.0, 125.5, 123.5, 123.4, 119.4, 115.7 (d, J ¼ 21.46 Hz), –OCH2CH3). 13C (125 MHz, CDCl3): d 159.9, 158.8, 139.9, 132.8,
110.5, 90.4, 88.8. IR (lm): 3054, 1585, 1504, 1220, 1157, 944, 129.3, 127.5, 115.5, 114.4, 114.1, 105.9, 91.1, 87.8, 63.4, 55.3,
833, 794 cmꢁ1. HRMS (EI) calcd for C20H13F [M+] 272.1001; 14.7. IR (lm): 2982, 2933, 2187, 1602, 1505, 1255, 1174, 1030,
1
found 272.1008.
960, 840 cmꢁ1. HRMS (EI) calcd for C19H18O2 [M+] 278.1307;
ꢀ
4d. Pale brown solid (0.066 g, 61%); m.p. 100–102 C, Rf ¼ found 278.1309.
0.48 (hexane). 1H NMR (500 MHz, CDCl3): d 8.17 (d, 1H, J ¼ 8.25
5e. Yellow solid (0.068 g, 69%); m.p. 88–90 ꢀC, Rf ¼ 0.10
Hz, Ar-H), 7.88–7.83 (m, 3H, Ar-H), 7.69 (d, 1H, J ¼ 7.05 Hz, Ar- (hexane). 1H NMR (500 MHz, CDCl3): d 7.36 (d, 2H, J ¼ 8.85 Hz,
H), 7.58–7.44 (m, 5H, Ar-H), 7.34 (d, 2H, J ¼ 8.55 Hz, Ar-H), 6.45 Ar-H), 7.25–7.21 (m, 1H, Ar-H), 7.06 (d, 1H, J ¼ 7.6 Hz, Ar-H),
(d, 1H, J ¼ 15.9 Hz). 13C (125 MHz, CDCl3): d 138.7, 134.2, 133.6, 7.02–6.98 (m, 2H, Ar-H), 6.88–6.86 (m, 3H, Ar-H), 6.23 (d, 1H,
133.5, 132.7, 130.8, 129.1, 128.7, 128.6, 126.4, 126.0, 125.5, J ¼ 16.2 Hz), 3.82 (s, 3H, –OCH3), 3.81 (s, 3H, –OCH3). 13C (125
123.4, 121.8, 110.4, 90.3, 90.1. IR (lm): 3042, 2923, 2193, 1508, MHz, CDCl3): d 160.1, 159.3, 141.0, 129.3, 129.1, 127.6, 124.5,
1394, 1089, 1011, 971, 827 cmꢁ1. HRMS (EI) calcd for C20H13Cl 124.0, 116.1, 114.7, 114.1, 105.5, 90.9, 89.1, 55.3, 55.2. IR (lm):
[M+] 288.0706; found 288.0705.
3031, 2958, 2192, 1600, 1510, 1249, 1175, 1032, 955, 814 cmꢁ1
.
4e. Pale brown solid (0.071 g, 66%); m.p. 86–88 ꢀC, Rf ¼ 0.21 HRMS (EI) calcd for C18H16O2 [M+] 264.1150; found 264.1152.
(hexane). 1H NMR (500 MHz, CDCl3): d 8.18 (d, 1H, J ¼ 8.55 Hz,
6a. Brown solid (0.089 g, 81%); m.p. 92–94 ꢀC, Rf ¼ 0.18
1
Ar-H), 7.86 (d, 1H, J ¼ 7.35 Hz, Ar-H), 7.83–7.79 (m, 2H, Ar-H), (EtOAc–hexane 1 : 99). H NMR (500 MHz, CDCl3): d 7.47–7.46
7.68 (d, 1H, J ¼ 7 Hz, Ar-H), 7.55–7.46 (m, 5H, Ar-H), 6.89 (m, 2H, Ar-H), 7.34–7.31 (m, 3H, Ar-H), 6.96 (d, 1H, J ¼ 16.15
(d, 2H, J ¼ 8.85 Hz, Ar-H), 6.46 (d, 1H, J ¼ 15.9 Hz), 3.84 (s, 3H, Hz), 6.65 (s, 2H, Ar-H), 6.30 (d, 1H, J ¼ 16.2 Hz), 3.89 (s, 6H,
–OCH3). 13C (125 MHz, CDCl3): d 159.6, 137.4, 133.9, 133.6, –OCH3), 3.86 (s, 3H, –OCH3). 13C (125 MHz, CDCl3): d 153.4,
133.0, 130.8, 128.8, 128.5, 126.3, 125.9, 125.5, 123.6, 123.3, 141.1, 138.7, 132.0, 131.4, 128.3, 128.2, 123.4, 107.6, 103.4, 91.8,
115.4, 114.0, 111.0, 91.6, 87.9, 55.3. IR (lm): 3042, 2835, 2192, 88.7, 60.9, 56.1. IR (lm): 2989, 2935, 1579, 1505, 1418, 1343,
1597, 1508, 1248, 1172, 1032, 946, 831 cmꢁ1. HRMS (EI) calcd 1240, 1127, 1005 cmꢁ1. HRMS (EI) calcd for C19H18O3 [M+]
for C21H16O [M+] 284.1201; found 284.1205.
294.1256; found 294.1255.
5a.19 Yellow solid (0.063 g, 71%); m.p. 86–88 ꢀC, Rf ¼ 0.29
6b. Brown solid (0.098 g, 85%); m.p. 84–86 ꢀC, Rf ¼ 0.18
(hexane). 1H NMR (500 MHz, CDCl3): d 7.47 (dd, 2H, J ¼ 7.8 Hz, (EtOAc–hexane 1 : 99). 1H NMR (500 MHz, CDCl3): d 7.36 (d, 2H,
J ¼ 1.65 Hz, Ar-H), 7.37 (d, 2H, J ¼ 8.85 Hz, Ar-H), 7.35–7.30 J ¼ 8.25 Hz, Ar-H), 7.14 (d, 2H, J ¼ 7.6 Hz, Ar-H), 6.94 (d, 1H, J ¼
(m, 3H, Ar-H), 7.00 (d, 1H, J ¼ 16.15 Hz), 6.88 (d, 2H, J ¼ 8.55 Hz, 16.15 Hz), 6.64 (s, 2H, Ar-H), 6.29 (d, 1H, J ¼ 16.2 Hz), 3.88
Ar-H), 6.24 (d, 1H, J ¼ 16.2 Hz), 3.82 (s, 3H, –OCH3). 13C (125 (s, 6H, –OCH3), 3.86 (s, 3H, –OCH3), 2.36 (s, 3H, –CH3). 13C (125
MHz, CDCl3): d 160.0, 140.8, 131.4, 129.2, 128.3, 127.9, 127.6, MHz, CDCl3): d 153.4, 140.7, 138.7, 138.3, 132.1, 131.3, 129.1,
123.6, 114.2, 105.6, 90.9, 89.2, 55.3. IR (lm): 3055, 2908, 2191, 120.3, 107.7, 103.3, 92.0, 88.1, 60.9, 56.1, 21.5. IR (lm): 2998,
1573, 1510, 1441, 1261, 1177, 1032, 819, 754 cmꢁ1. HRMS (EI) 2936, 1578, 1505, 1462, 1419, 1342, 1239, 1127, 949 cmꢁ1. HRMS
calcd for C17H14O [M+] 234.1045; found 234.1044.
5b. Pale yellow solid (0.060 g, 63%); m.p. 112–114 C, Rf ¼
(ESI) calcd for C20H21O3 [M + H]+ 309.1491; found 309.1492.
6c. Yellow solid (0.088 g, 75%); m.p. 76–78 ꢀC, Rf ¼ 0.29
ꢀ
1
0.25 (hexane). H NMR (500 MHz, CDCl3): d 7.46–7.42 (m, 2H, (EtOAc–hexane 1 : 9). 1H NMR (500 MHz, CDCl3): d 7.45–7.42
Ar-H), 7.36 (d, 2H, J ¼ 8.85 Hz, Ar-H), 7.02 (d, 2H, J ¼ 8.55 Hz, Ar- (m, 2H, Ar-H), 7.02 (t, 2H, J ¼ 8.7 Hz, Ar-H), 6.95 (d, 1H, J ¼ 16.2
H), 6.98 (d, 1H, J ¼ 15.6 Hz), 6.88 (d, 2H, J ¼ 8.85 Hz, Ar-H), 6.22 Hz), 6.64 (s, 2H, Ar-H), 6.27 (d, 1H, J ¼ 16.2 Hz), 3.88 (s, 6H,
(d, 1H, J ¼ 16.2 Hz), 3.83 (s, 3H, –OCH3). 13C (125 MHz, CDCl3): d –OCH3), 3.86 (s, 3H, –OCH3). 13C (125 MHz, CDCl3): d 162.4 (d,
162.3 (d, J ¼ 247.16 Hz), 160.1, 140.9, 133.2 (d, J ¼ 7.2 Hz), 129.1, J ¼ 248.36 Hz), 153.4, 141.1, 138.8, 133.3 (d, J ¼ 8.4 Hz), 131.9,
127.6, 119.6, 115.6 (d, J ¼ 21.58 Hz), 114.2, 105.4, 89.8, 88.9, 119.5, 115.6 (d, J ¼ 21.58 Hz), 107.3, 103.4, 90.6, 88.4, 60.9, 56.1.
55.3. IR (lm): 2967, 2358, 1601, 1504, 1381, 1250, 1089, 1031, IR (lm): 2999, 2937, 2190, 1578, 1504, 1419, 1342, 1233, 1127,
956, 836, 809 cmꢁ1. HRMS (EI) calcd for C17H13FO [M+] 950, 812 cmꢁ1. HRMS (ESI) calcd for C19H18FO3 [M + H]+
252.0950; found 252.0952.
313.1240; found 313.1245.
5c.20 Pale brown solid (0.063 g, 62%); m.p. 126–128 ꢀC, Rf ¼
6d. Yellow solid (0.088 g, 71%); m.p. 66–68 ꢀC, Rf ¼ 0.19
0.30 (hexane). 1H NMR (500 MHz, CDCl3): d 7.37 (t, 4H, J ¼ 8.55 (EtOAc–hexane 1 : 99). 1H NMR (500 MHz, CDCl3): d 7.38 (d, 2H,
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8f. Yellow solid (0.065 g, 65%); m.p. 68–70 ꢀC, Rf ¼ 0.30
(hexane). 1H NMR (500 MHz, CDCl3): d 7.34 (d, 2H, J ¼ 8.3 Hz,
Ar-H), 7.30 (d, 2H, J ¼ 8.6 Hz, Ar-H), 7.25–7.22 (m, 1H, Ar-H),
7.07 (d, 1H, J ¼ 7.45 Hz, Ar-H), 6.99–6.97 (m, 2H, Ar-H), 6.88
(dd, 1H, J ¼ 8.3 Hz, J ¼ 2 Hz, Ar-H), 6.35 (d, 1H, J ¼ 16.35 Hz),
3.81 (s, 3H, –OCH3). 13C (125 MHz, CDCl3): d 159.3, 139.9, 134.8,
134.3, 129.4, 128.9, 127.4, 124.2, 124.1, 116.3, 114.9, 108.7, 92.2,
88.4, 55.2. IR (lm): 3032, 2938, 2194, 1724, 1592, 1489, 1218,
1088, 959, 806 cmꢁ1. HRMS (EI) calcd for C17H13ClO [M+]
268.0655; found 268.0656.
8g.19 Yellow solid (0.072 g, 71%); m.p. 132–134 ꢀC, Rf ¼ 0.24
(hexane). 1H NMR (500 MHz, CDCl3): d 7.41 (dd, 2H, J ¼ 8.85 Hz,
J ¼ 1.5 Hz, Ar-H), 7.34 (d, 2H, J ¼ 8.55 Hz, Ar-H), 7.30 (d, 2H, J ¼
8.25 Hz, Ar-H), 6.94 (d, 1H, J ¼ 16.15 Hz), 6.86 (dd, 2H, J ¼ 8.85
Hz, J ¼ 1.2 Hz, Ar-H), 6.35 (d, 1H, J ¼ 16.2 Hz), 3.82 (s, 3H,
–OCH3). 13C (125 MHz, CDCl3): d 159.7, 139.0, 134.9, 134.0,
133.0, 128.9, 127.3, 115.3, 114.0, 109.0, 92.4, 87.3, 55.3. IR (lm):
J ¼ 8.55 Hz, Ar-H), 7.30 (d, 2H, J ¼ 8.85 Hz, Ar-H), 6.96 (d, 1H, J ¼
15.9 Hz), 6.64 (s, 2H, Ar-H), 6.27 (d, 1H, J ¼ 16.2 Hz), 3.88 (s, 6H,
–OCH3), 3.86 (s, 3H, –OCH3). 13C (125 MHz, CDCl3): d 153.4,
141.5, 138.9, 134.1, 132.6, 131.8, 128.7, 121.9, 107.2, 103.5, 90.6,
89.7, 60.9, 56.1. IR (lm): 2936, 2837, 2193, 1577, 1505, 1488,
1342, 1128, 949, 790 cmꢁ1. HRMS (ESI) calcd for C19H18ClO3 [M
+ H]+ 329.0944; found 329.0948.
ꢀ
7a. Pale yellow solid (0.051 g, 56%); m.p. 166–168 C, Rf ¼
1
0.54 (EtOAc–hexane 1 : 99). H NMR (500 MHz, CDCl3): d 7.62
(d, 2H, J ¼ 8.3 Hz, Ar-H), 7.48 (d, 2H, J ¼ 8.05 Hz, Ar-H), 7.37
(d, 2H, J ¼ 8 Hz, Ar-H), 7.15 (d, 2H, J ¼ 7.7 Hz, Ar-H), 6.99 (d, 1H,
J ¼ 16 Hz), 6.49 (d, 1H, J ¼ 16.5 Hz), 2.37 (s, 3H, –CH3). 13C
(125 MHz, CDCl3): d 140.7, 139.0, 138.5, 132.5, 131.5, 129.2,
126.5, 119.7, 118.8, 112.3, 111.4, 94.5, 87.5, 21.5. IR (lm): 3054,
2963, 2926, 2225, 2193, 1723, 1599, 1412, 1265, 970, 950, 818,
705 cmꢁ1. HRMS (EI) calcd for C18H13N [M+] 243.1048; found
243.1047.
2964, 2841, 2190, 1597, 1508, 1249, 1031, 957, 837, 810 cmꢁ1
.
8a.19 Pale yellow solid (0.068 g, 77%); m.p. 108–110 C, Rf ¼
ꢀ
1
HRMS (EI) calcd for C17H13ClO [M+] 268.0655; found 268.0656.
0.61 (hexane). H NMR (500 MHz, CDCl3): d 7.49–7.47 (m, 2H,
ꢀ
Ar-H), 7.36–7.30 (m, 7H, Ar-H), 6.99 (d, 1H, J ¼ 16.2 Hz), 6.36
(d, 1H, J ¼ 16.15 Hz). 13C (125 MHz, CDCl3): d 139.8, 134.8,
134.3, 131.5, 128.9, 128.4, 128.3, 127.4, 123.2, 108.8, 92.3, 88.5.
IR (lm): 3049, 2922, 1484, 1069, 960, 809, 757, 688 cmꢁ1. HRMS
(EI) calcd for C16H11Cl [M+] 238.0549; found 238.0541.
8h. Pale yellow solid (0.069 g, 65%); m.p. 150–152 C, Rf ¼
0.33 (hexane). 1H NMR (500 MHz, CDCl3): d 7.39 (d, 2H, J ¼ 8.9
Hz, Ar-H), 7.33 (d, 2H, J ¼ 8.9 Hz, Ar-H), 7.30 (d, 2H, J ¼ 8.55 Hz,
Ar-H), 6.93 (d, 1H, J ¼ 16.2 Hz), 6.85 (d, 2H, J ¼ 8.85 Hz, Ar-H),
6.35 (d, 1H, J ¼ 16.2 Hz), 4.04 (q, 2H, J ¼ 7.03 Hz, –OCH2CH3),
1.42 (t, 3H, J ¼ 7.02 Hz, –OCH2CH3). 13C (125 MHz, CDCl3): d
159.0, 138.9, 134.9, 134.0, 132.9, 128.9, 127.3, 115.1, 114.5,
109.1, 92.5, 87.3, 63.5, 14.7. IR (lm): 3030, 2934, 2189, 1598,
1509, 1288, 1251, 1174, 1088, 958, 826, 809 cmꢁ1. HRMS (EI)
calcd for C18H15ClO [M+] 282.0811; found 282.0816.
8b. Colourless solid (0.067 g, 71%); m.p. 76–78 ꢀC, Rf ¼ 0.53
(hexane). 1H NMR (500 MHz, CDCl3): d 7.36–7.27 (m, 6H, Ar-H),
7.22 (t, 1H, J ¼ 7.62 Hz, Ar-H), 7.14 (d, 1H, J ¼ 7.3 Hz, Ar-H), 6.97
(d, 1H, J ¼ 16.2 Hz), 6.35 (d, 1H, J ¼ 16.2 Hz), 2.35 (s, 3H, –CH3).
13C (125 MHz, CDCl3): d 139.7, 138.0, 134.8, 134.2, 132.1, 129.2,
128.9, 128.6, 128.2, 127.4, 123.0, 108.9, 92.5, 88.2, 21.2. IR (lm):
3033, 2919, 1490, 1404, 1092, 956, 853, 807, 786 cmꢁ1. HRMS
(EI) calcd for C17H13Cl [M+] 252.0706; found 252.0709.
9a. Pale yellow solid (0.068 g, 67%); m.p. 56–58 ꢀC, Rf ¼ 0.30
(hexane). 1H NMR (500 MHz, CDCl3): d 7.42–7.38 (m, 3H, Ar-H),
7.27–7.24 (m, 3H, Ar-H), 6.91 (d, 1H, J ¼ 16.15 Hz), 6.86 (d, 2H,
J ¼ 8.85 Hz, Ar-H), 6.37 (d, 1H, J ¼ 16.15 Hz), 3.82 (s, 3H,
–OCH3). 13C (125 MHz, CDCl3): d 159.7, 138.8, 138.3, 134.7,
133.0, 129.9, 128.3, 126.0, 124.4, 115.3, 114.0, 110.0, 92.8, 87.2,
55.3. IR (lm): 2838, 2191, 1597, 1507, 1246, 1172, 954, 836,
781 cmꢁ1. HRMS (EI) calcd for C17H13ClO [M+] 268.0655; found
268.0658.
10a.21 Deep brown liquid (0.054 g, 74%); Rf ¼ 0.43 (hexane).
1H NMR (500 MHz, CDCl3): d 7.47–7.40 (m, 3H, Ar-H), 7.35–7.31
(m, 3H, Ar-H), 6.79 (d, 1H, J ¼ 16.2 Hz), 6.43–6.42 (m, 1H, Ar-H),
6.36 (d, 1H, J ¼ 3.35 Hz, Ar-H), 6.29 (d, 1H, J ¼ 15.9 Hz). 13C (125
MHz, CDCl3): d 152.2, 143.0, 131.4, 128.3, 128.2, 128.1, 123.4,
111.8, 110.1, 106.1, 92.5, 88.8. IR (lm): 2926, 1726, 1592, 1491,
1260, 1015, 944, 757, 690 cmꢁ1. HRMS (EI) calcd for C14H10O
[M+] 194.0732; found 194.0730.
8c. Colourless solid (0.066 g, 70%); m.p. 164–166 ꢀC, Rf ¼
1
0.41 (hexane). H NMR (500 MHz, CDCl3): d 7.38–7.29 (m, 6H,
Ar-H), 7.15 (d, 2H, J ¼ 8 Hz, Ar-H), 6.96 (d, 1H, J ¼ 16.3 Hz), 6.36
(d, 1H, J ¼ 16.3 Hz), 2.36 (s, 3H, –CH3). 13C (125 MHz, CDCl3): d
139.4, 138.5, 134.9, 134.1, 131.4, 129.1, 128.9, 127.4, 120.1,
108.9, 92.5, 87.9, 21.5. IR (lm): 3028, 2915, 2191, 1488, 1401,
1265, 1091, 959, 814, 739 cmꢁ1. HRMS (EI) calcd for C17H13Cl
[M+] 252.0706; found 252.0701.
ꢀ
8d. Pale yellow solid (0.064 g, 66%); m.p. 128–130 C, Rf ¼
1
0.54 (hexane). H NMR (500 MHz, CDCl3): d 7.46–7.43 (m, 2H,
Ar-H), 7.33 (q, 4H, J ¼ 8.66 Hz, Ar-H), 7.03 (t, 2H, J ¼ 8.55 Hz, Ar-
H), 6.97 (d, 1H, J ¼ 16.2 Hz), 6.33 (d, 1H, J ¼ 16.15 Hz). 13C (125
MHz, CDCl3): d 162.5 (d, J ¼ 248.36 Hz), 139.9, 134.7, 134.4,
133.4 (d, J ¼ 8.4 Hz), 128.9, 127.4, 119.3, 115.7 (d, J ¼ 22.8 Hz),
108.6, 91.2, 88.2. IR (lm): 3056, 2923, 1899, 1581, 1490, 1405,
1093, 836, 809 cmꢁ1. HRMS (EI) calcd for C16H10ClF [M+]
256.0455; found 256.0456.
8e.18 Yellow solid (0.084 g, 82%); m.p. 158–160 ꢀC, Rf ¼ 0.56
(hexane). 1H NMR (500 MHz, CDCl3): d 7.40–7.30 (m, 8H, Ar-H),
6.98 (d, 1H, J ¼ 16.2 Hz), 6.33 (d, 1H, J ¼ 16.15 Hz). 13C (125
MHz, CDCl3): d 140.2, 134.6, 134.4, 134.3, 132.7, 128.9, 128.7,
127.5, 121.7, 108.4, 91.1, 89.5. IR (lm): 3027, 1587, 1488, 1095,
1013, 963, 829, 811 cmꢁ1. HRMS (EI) calcd for C16H10Cl2 [M+]
272.0160; found 272.0164.
10b. Deep brown liquid (0.056 g, 72%); Rf ¼ 0.39 (hexane). 1H
NMR (500 MHz, CDCl3): d 7.39 (br.s, 1H, Ar-H), 7.36 (d, 2H, J ¼
8.25 Hz, Ar-H), 7.13 (d, 2H, J ¼ 8.25 Hz, Ar-H), 6.77 (d, 1H, J ¼
15.9 Hz), 6.42–6.41 (m, 1H, Ar-H), 6.35 (d, 1H, J ¼ 3.05 Hz, Ar-H),
6.28 (d, 1H, J ¼ 15.9 Hz), 2.36 (s, 3H, –CH3). 13C (125 MHz,
CDCl3): d 152.3, 142.9, 138.3, 131.3, 129.1, 127.9, 120.3, 111.8,
109.8, 106.3, 92.8, 88.2, 21.5. IR (lm): 2919, 2189, 1777, 1603,
1508, 1480, 1261, 1014, 943, 818, 738, 591 cmꢁ1. HRMS (EI)
calcd for C15H12O [M+] 208.0888; found 208.0880.
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10c. Deep brown liquid (0.053 g, 68%); Rf ¼ 0.42 (hexane). 1H
NMR (500 MHz, CDCl3): d 7.44–7.40 (m, 3H, Ar-H), 7.02 (t, 2H,
J ¼ 8.85 Hz, Ar-H), 6.77 (d, 1H, J ¼ 15.9 Hz), 6.43–6.41 (m, 1H, Ar-
7.03 (d, 1H, J ¼ 3.04 Hz, Ar-H), 7.00–6.98 (m, 1H, Ar-H), 6.86
(d, 2H, J ¼ 8.55 Hz, Ar-H), 6.19 (d, 1H, J ¼ 15.85 Hz), 3.82 (s, 3H,
–OCH3). 13C (125 MHz, CDCl3): d 159.5, 141.6, 133.2, 132.9,
127.7, 126.7, 125.2, 115.4, 114.0, 107.6, 92.2, 87.4, 55.3. IR (lm):
2959, 2928, 2190, 1608, 1505, 1249, 1035, 832, 703 cmꢁ1. HRMS
(EI) calcd for C15H12OS [M+] 240.0609; found 240.0603.
H), 6.36 (d, 1H, J ¼ 3.35 Hz, Ar-H), 6.25 (d, 1H, J ¼ 16.2 Hz). 13
C
(125 MHz, CDCl3): d 162.4 (d, J ¼ 248.36 Hz), 152.2, 143.1, 133.3
(d, J ¼ 8.4 Hz), 128.3, 119.5, 115.6 (d, J ¼ 21.6 Hz), 111.9, 110.1,
105.9, 91.4, 88.5. IR (lm): 3043, 2926, 1595, 1505, 1219, 1156,
1015, 948, 837, 742 cmꢁ1. HRMS (EI) calcd for C14H9FO [M+]
212.0637; found 212.0631.
12a. Bright yellow solid (0.082 g, 61%); m.p. 140–142 ꢀC, Rf ¼
0.21 (hexane). 1H NMR (500 MHz, CDCl3): d 7.42 (br.s, 1H, Ar-H),
7.38–7.33 (m, 7H, Ar-H), 7.14 (d, 4H, J ¼ 8.25 Hz, Ar-H), 7.01
(d, 2H, J ¼ 16.2 Hz), 6.40 (d, 2H, J ¼ 16.2 Hz), 2.36 (s, 6H, –CH3).
13C (125 MHz, CDCl3): d 140.3, 138.4, 136.9, 131.4, 129.1, 126.1,
124.3, 120.2, 108.9, 92.3, 88.1, 21.5. IR (lm): 3026, 2917, 2193,
1508, 1262, 1106, 1021, 952, 814, 792 cmꢁ1. HRMS (ESI) calcd
for C28H26N [M + NH4]+ 376.2065; found 376.2067.
10d. Deep brown liquid (0.056 g, 62%); Rf ¼ 0.21 (hexane). 1H
NMR (500 MHz, CDCl3): d 7.39–7.37 (m, 3H, Ar-H), 6.84 (dd, 2H,
J ¼ 8.85 Hz, J ¼ 1.82 Hz, Ar-H), 6.74 (d, 1H, J ¼ 15.85 Hz), 6.42–
6.40 (m, 1H, Ar-H), 6.34–6.33 (m, 1H, Ar-H), 6.27 (d, 1H, J ¼ 15.9
Hz), 4.04 (q, 2H, J ¼ 6.93 Hz, –OCH2CH3), 1.42 (t, 3H, J ¼ 6.87
Hz, –OCH2CH3). 13C (125 MHz, CDCl3): d 158.9, 152.4, 142.8,
132.9, 127.4, 115.3, 114.5, 111.8, 109.6, 106.5, 92.7, 87.5, 63.5,
14.7. IR (lm): 2974, 2188, 1600, 1508, 1246, 1176, 947, 738,
591 cmꢁ1. HRMS (EI) calcd for C16H14O2 [M+] 238.0994; found
238.0993.
12b. Yellow solid (0.096 g, 64%); m.p. 158–160 ꢀC, Rf ¼ 0.51
1
(EtOAc–hexane 1 : 99). H NMR (500 MHz, CDCl3): d 7.43–7.26
(m, 12H, Ar-H), 7.04 (d, 2H, J ¼ 16.2 Hz), 6.39 (d, 2H, J ¼ 16.2
Hz). 13C (125 MHz, CDCl3): d 141.1, 136.7, 134.3, 132.7, 129.2,
128.7, 126.4, 124.4, 121.8, 108.5, 90.9, 89.6. IR (lm): 2924, 2854,
2141, 1600, 1489, 1256, 1092, 1013, 828, 738 cmꢁ1. HRMS (EI)
calcd for C26H16Cl2 [M+] 398.0629; found 398.0612.
11a.21 Brown solid (0.056 g, 71%); m.p. 96–98 C, Rf ¼ 0.51
ꢀ
(hexane). 1H NMR (500 MHz, CDCl3): d 7.40–7.38 (m, 2H, Ar-H),
12c. Yellow solid (0.110 g, 70%); m.p. 138–140 ꢀC, Rf ¼ 0.40
7.26–7.24 (m, 3H, Ar-H), 7.19–7.14 (m, 1H, Ar-H), 7.07 (d, 1H, J ¼
1
15.9 Hz), 6.98–6.92 (m, 2H, Ar-H), 6.13 (d, 1H, J ¼ 15.9 Hz). 13
C
(EtOAc–hexane 1 : 99). H NMR (500 MHz, CDCl3): d 7.41–7.40
(m, 5H, Ar-H), 7.34–7.31 (m, 3H, Ar-H), 6.99 (d, 2H, J ¼ 16.15
Hz), 6.85 (d, 4H, J ¼ 8.85 Hz, Ar-H), 6.40 (d, 2H, J ¼ 16.5 Hz), 4.05
(q, 4H, J ¼ 6.92 Hz, –OCH2CH3), 1.42 (t, 6H, J ¼ 7.02 Hz,
–OCH2CH3). 13C (125 MHz, CDCl3): d 159.0, 139.9, 136.9, 133.0,
129.1, 126.0, 124.2, 115.2, 114.5, 109.0, 92.3, 87.4, 63.5, 14.7. IR
(lm): 2978, 2933, 2192, 1598, 1508, 1245, 838 cmꢁ1. HRMS
(ESI) calcd for C30H27O2 [M + H]+ 419.2011; found 419.2017.
13a.19 Pale yellow solid (0.081 g, 77%); m.p. 106–108 ꢀC, Rf ¼
(125 MHz, CDCl3): d 141.4, 134.0, 131.4, 128.3, 128.1, 127.7,
127.1, 125.5, 123.3, 107.3, 92.1, 88.6. IR (lm): 3031, 1587, 1486,
937, 853, 757, 688 cmꢁ1. HRMS (EI) calcd for C14H10S [M+]
210.0503; found 210.0509.
11b. Pale brown solid (0.058 g, 69%); m.p. 100–102 ꢀC, Rf ¼
0.42 (hexane). 1H NMR (500 MHz, CDCl3): d 7.35 (d, 2H, J ¼ 7.95
Hz, Ar-H), 7.21 (d, 1H, J ¼ 5.2 Hz, Ar-H), 7.14–7.01 (m, 3H, Ar-H),
7.04 (d, 1H, J ¼ 3.05 Hz, Ar-H), 7.01–6.99 (m, 1H, Ar-H), 6.19 (d,
1H, J ¼ 15.9 Hz), 2.36 (s, 3H, –CH3). 13C (125 MHz, CDCl3): d
141.6, 138.3, 133.6, 131.3, 129.1, 127.7, 126.9, 125.3, 120.2,
107.5, 92.3, 88.0, 21.5. IR (lm): 3029, 2917, 2189, 1504, 1427,
942, 816, 700 cmꢁ1. HRMS (EI) calcd for C15H12S [M+] 224.0660;
found 224.0666.
1
0.52 (hexane). H NMR (500 MHz, CDCl3): d 7.48–7.46 (m, 4H,
Ar-H), 7.35–7.32 (m, 3H, Ar-H), 7.28 (d, 2H, J ¼ 8.55 Hz, Ar-H),
6.97 (d, 1H, J ¼ 16.5 Hz), 6.38 (d, 1H, J ¼ 16.15 Hz). 13C (125
MHz, CDCl3): d 139.8, 135.2, 131.9, 131.5, 128.3, 128.3, 127.7,
123.2, 122.5, 108.9, 92.4, 88.5. IR (lm): 3027, 1484, 1441, 1072,
957, 809, 755, 690 cmꢁ1. HRMS (EI) calcd for C16H11Br [M+]
282.0044; found 282.0045.
13b. Yellow solid (0.072 g, 65%); m.p. 86–88 ꢀC, Rf ¼ 0.47
(hexane). 1H NMR (500 MHz, CDCl3): d 7.46 (d, 2H, J ¼ 8.55 Hz,
Ar-H), 7.29–7.25 (m, 4H, Ar-H), 7.21 (t, 1H, J ¼ 7.62 Hz, Ar-H),
7.13 (d, 1H, J ¼ 7.6 Hz, Ar-H), 6.95 (d, 1H, J ¼ 16.15 Hz), 6.36
(d, 1H, J ¼ 16.2 Hz), 2.34 (s, 3H, –CH3). 13C (125 MHz, CDCl3): d
139.7, 138.0, 135.3, 132.1, 131.9, 129.2, 128.6, 128.2, 127.7,
123.0, 122.4, 109.0, 92.6, 88.2, 21.2. IR (lm): 3033, 2919, 2191,
1578, 1482, 1400, 1072, 965, 805, 785 cmꢁ1. HRMS (EI) calcd for
11c. Pale brown solid (0.070 g, 82%); m.p. 82–84 ꢀC, Rf ¼ 0.47
(hexane). 1H NMR (500 MHz, CDCl3): d 7.44–7.42 (m, 2H, Ar-H),
7.22 (d, 1H, J ¼ 5.2 Hz, Ar-H), 7.13 (d, 1H, J ¼ 15.9 Hz), 7.06–6.99
(m, 4H, Ar-H), 6.17 (d, 1H, J ¼ 15.9 Hz). 13C (125 MHz, CDCl3): d
162.4 (d, J ¼ 248.36 Hz), 141.4, 134.1, 133.3 (d, J ¼ 8.4 Hz), 127.7,
127.1, 125.5, 119.4, 115.6 (d, J ¼ 22.78 Hz), 107.0, 90.9, 88.3. IR
(lm): 2923, 1898, 1604, 1501, 1218, 1155, 948, 837, 707 cmꢁ1
.
HRMS (EI) calcd for C14H9FS [M+] 228.0409; found 228.0404.
11d. Brown liquid (0.064 g, 71%); Rf ¼ 0.24 (hexane). 1H NMR
(500 MHz, CDCl3): d 7.25–7.21 (m, 2H, Ar-H), 7.14 (d, 1H, J ¼
16.2 Hz), 7.06–7.04 (m, 2H, Ar-H), 7.00–6.98 (m, 2H, Ar-H), 6.87
(dd, 1H, J ¼ 8.25 Hz, J ¼ 2.45 Hz, Ar-H), 6.18 (d, 1H, J ¼ 16.2 Hz),
3.81 (s, 3H, –OCH3). 13C (125 MHz, CDCl3): d 159.3, 141.4, 134.1,
129.4, 127.7, 127.1, 125.5, 124.3, 124.0, 116.1, 114.8, 107.2, 92.0,
88.5, 55.2. IR (lm): 3071, 2999, 2935, 2191, 1593, 1573, 1488,
1426, 1045, 853, 778, 685 cmꢁ1. HRMS (EI) calcd for C15H12OS
[M+] 240.0609; found 240.0602.
C
17H13Br [M+] 296.0201; found 296.0201.
13c.19 Pale yellow solid (0.080 g, 72%); m.p. 178–180 ꢀC, Rf ¼
0.54 (hexane). 1H NMR (500 MHz, CDCl3): d 7.46 (d, 2H, J ¼ 8.25
Hz, Ar-H), 7.37 (d, 2H, J ¼ 7.95 Hz, Ar-H), 7.28 (d, 2H, J ¼ 8.25
Hz, Ar-H), 7.14 (d, 2H, J ¼ 8.25 Hz, Ar-H), 6.94 (d, 1H, J ¼ 16.2
Hz), 6.37 (d, 1H, J ¼ 16.2 Hz), 2.36 (s, 3H, –CH3). 13C (125 MHz,
CDCl3): d 139.4, 138.5, 135.3, 131.8, 131.4, 129.1, 127.6, 122.3,
120.1, 109.1, 92.6, 87.9, 21.5. IR (lm): 3028, 2937, 1400, 958,
819, 807 cmꢁ1. HRMS (EI) calcd for C17H13Br [M+] 296.0201;
found 296.0207.
11e. Pale brown solid (0.052 g, 58%); m.p. 84–86 ꢀC, Rf ¼ 0.24
(hexane). 1H NMR (500 MHz, CDCl3): d 7.39 (d, 2H, J ¼ 8.85 Hz,
Ar-H), 7.20 (d, 1H, J ¼ 4.85 Hz, Ar-H), 7.09 (d, 1H, J ¼ 15.9 Hz),
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13d. Colourless solid (0.090 g, 80%); m.p. 90–92 ꢀC, Rf ¼ 0.53
Hz, Ar-H), 6.91 (d, 1H, J ¼ 16.2 Hz), 6.84 (d, 2H, J ¼ 8.25 Hz,
Ar-H), 6.36 (d, 1H, J ¼ 16.2 Hz), 4.04 (q, 2H, J ¼ 6.92 Hz,
–OCH2CH3), 1.41 (t, 3H, J ¼ 6.85 Hz, –OCH2CH3). 13C (125 MHz,
CDCl3): d 159.1, 138.9, 135.4, 132.9, 131.8, 127.6, 122.2, 115.1,
114.5, 109.2, 92.6, 87.3, 63.5, 14.7. IR (lm): 3028, 2188, 1724,
(hexane). 1H NMR (500 MHz, CDCl3): d 7.47 (d, 2H, J ¼ 8.3 Hz,
Ar-H), 7.31–7.23 (m, 4H, Ar-H), 7.16–7.15 (m, 1H, Ar-H), 7.04–
7.00 (m, 1H, Ar-H), 6.97 (d, 1H, J ¼ 16.35 Hz), 6.34 (d, 1H, J ¼
16.05 Hz). 13C (125 MHz, CDCl3): d 162.3 (d, J ¼ 244.76 Hz),
140.6, 135.0, 131.9, 129.9 (d, J ¼ 8.4 Hz), 127.7, 127.4, 125.0
(d, J ¼ 9.6 Hz), 122.7, 118.2 (d, J ¼ 21.6 Hz), 115.6 (d, J ¼ 21.6
Hz), 108.4, 90.9, 89.4. IR (lm): 3033, 2922, 1575, 1482, 1432,
1400, 1263, 1151, 1074, 946, 807 cmꢁ1. HRMS (EI) calcd for
1598, 1508, 1394, 1288, 1250, 1174, 1114, 1045, 958, 807 cmꢁ1
.
HRMS (EI) calcd for C18H15BrO [M+] 326.0306; found 326.0303.
14a. Pale yellow solid (0.065 g, 60%); m.p. 94–96 ꢀC, Rf ¼ 0.51
(hexane). 1H NMR (400 MHz, CDCl3): d 7.45 (d, 2H, J ¼ 8.72 Hz,
Ar-H), 7.27–7.22 (m, 4H, Ar-H), 7.00–6.91 (m, 2H, Ar-H), 6.36
(d, 1H, J ¼ 16.48 Hz). 13C (100 MHz, CDCl3): d 139.7, 135.1,
131.9, 127.7, 127.5, 127.2, 123.3, 122.6, 108.5, 92.4, 85.6. IR
(lm): 3098, 2184, 1582, 1485, 1421, 1400, 1072, 956, 853,
807 cmꢁ1. HRMS (EI) calcd for C14H9BrS [M+] 287.9608; found
287.9601.
C
16H10BrF [M+] 299.9950; found 299.9955.
13e. Yellow solid (0.079 g, 70%); m.p. 122–124 ꢀC, Rf ¼ 0.52
(hexane). 1H NMR (500 MHz, CDCl3): d 7.48–7.43 (m, 4H, Ar-H),
7.28 (d, 2H, J ¼ 8.55 Hz, Ar-H), 7.03 (t, 2H, J ¼ 8.4 Hz, Ar-H), 6.95
(d, 1H, J ¼ 16.5 Hz), 6.35 (d, 1H, J ¼ 16.15 Hz). 13C (125 MHz,
CDCl3): d 162.5 (d, J ¼ 248.36 Hz), 139.9, 135.1, 133.4 (d, J ¼ 8.4
Hz), 131.9, 127.7, 122.5, 119.3, 115.7 (d, J ¼ 21.6 Hz), 108.7, 91.2,
88.2. IR (lm): 3065, 1505, 1221, 964, 836, 807 cmꢁ1. HRMS (EI)
calcd for C16H10BrF [M+] 299.9950; found 299.9953.
15a. Pale brown solid (0.073 g, 69%); m.p. 54–56 ꢀC, Rf ¼ 0.43
(hexane). 1H NMR (500 MHz, CDCl3): d 7.57 (br.s, 1H, Ar-H),
7.50–7.48 (m, 2H, Ar-H), 7.42 (d, 1H, J ¼ 7.75 Hz, Ar-H), 7.35–
7.33 (m, 4H, Ar-H), 7.21 (t, 1H, J ¼ 7.87 Hz, Ar-H), 6.95 (d, 1H, J ¼
16.05 Hz), 6.39 (d, 1H, J ¼ 16.3 Hz). 13C (125 MHz, CDCl3): d
139.5, 138.4, 131.5, 131.3, 130.2, 129.0, 128.3, 124.8, 123.1,
122.9, 109.7, 92.6, 88.3. IR (lm): 3057, 2195, 1589, 1561, 1489,
1473, 1422, 1071, 949, 776, 756 cmꢁ1. HRMS (EI) calcd for
13f. Yellow solid (0.084 g, 71%); m.p. 88–90 ꢀC, Rf ¼ 0.49
(hexane). 1H NMR (500 MHz, CDCl3): d 7.47–7.44 (m, 3H, Ar-H),
7.34–7.32 (m, 1H, Ar-H), 7.30–7.23 (m, 4H, Ar-H), 6.97 (d, 1H, J ¼
16.35 Hz), 6.34 (d, 1H, J ¼ 16.35 Hz). 13C (125 MHz, CDCl3): d
140.6, 135.0, 134.2, 131.9, 131.3, 129.6, 129.5, 128.5, 127.8,
124.9, 122.7, 108.4, 90.8, 89.7. IR (lm): 3033, 2923, 2195, 1615,
1587, 1471, 1303, 1072, 1008, 948, 799, 779 cmꢁ1. HRMS (EI)
calcd for C16H10BrCl [M+] 315.9654; found 315.9653.
13g. Yellow solid (0.080 g, 67%); m.p. 162–164 ꢀC, Rf ¼ 0.59
(hexane). 1H NMR (500 MHz, CDCl3): d 7.47 (d, 2H, J ¼ 8.6 Hz,
Ar-H), 7.39 (d, 2H, J ¼ 8.6 Hz, Ar-H), 7.31–7.26 (m, 4H, Ar-H),
6.96 (d, 1H, J ¼ 16 Hz), 6.35 (d, 1H, J ¼ 16.3 Hz). 13C (125
MHz, CDCl3): d 140.3, 135.0, 134.3, 132.7, 131.9, 128.7, 127.7,
122.6, 121.7, 108.5, 91.2, 89.5. IR (lm): 3027, 1583, 1486, 1396,
1090, 963, 830, 809 cmꢁ1. HRMS (EI) calcd for C16H10BrCl [M+]
315.9654; found 315.9655.
C
16H11Br [M+] 282.0044; found 282.0045.
15b. Pale yellow solid (0.069 g, 62%); m.p. 66–68 ꢀC, Rf ¼ 0.50
(hexane). 1H NMR (500 MHz, CDCl3): d 7.55 (s, 1H, Ar-H), 7.41–
7.36 (m, 3H, Ar-H), 7.33 (d, 1H, J ¼ 7.7 Hz, Ar-H), 7.20 (t, 1H, J ¼
7.72 Hz, Ar-H), 7.14 (d, 2H, J ¼ 7.7 Hz, Ar-H), 6.92 (d, 1H, J ¼
16.35 Hz), 6.38 (d, 1H, J ¼ 16.35 Hz), 2.36 (s, 3H, –CH3). 13C (125
MHz, CDCl3): d 139.0, 138.6, 138.5, 131.4, 131.2, 130.2, 129.1,
129.0, 124.8, 122.9, 120.0, 109.9, 92.9, 87.7, 21.5. IR (lm): 3028,
2918, 2190, 1587, 1558, 1377, 1072, 954, 820, 782, 682 cmꢁ1
HRMS (EI) calcd for C17H13Br [M+] 296.0201; found 296.0208.
.
15c. Yellow solid (0.076 g, 64%); m.p. 76–78 ꢀC, Rf ¼ 0.55
(hexane). 1H NMR (500 MHz, CDCl3): d 7.56 (s, 1H, Ar-H), 7.43–
7.19 (m, 7H, Ar-H), 6.95 (d, 1H, J ¼ 16.15 Hz), 6.36 (d, 1H, J ¼
16.2 Hz). 13C (125 MHz, CDCl3): d 139.9, 138.2, 134.4, 132.7,
131.5, 130.2, 129.1, 128.7, 124.9, 122.9, 121.6, 109.4, 91.4, 89.3.
13h. Yellow solid (0.096 g, 82%); m.p. 70–72 ꢀC, Rf ¼ 0.23
(hexane). 1H NMR (500 MHz, CDCl3): d 7.46 (d, 2H, J ¼ 8.6 Hz,
Ar-H), 7.27 (d, 2H, J ¼ 8.55 Hz, Ar-H), 7.25–7.22 (m, 1H, Ar-H),
7.06 (dd, 1H, J ¼ 7.75 Hz, J ¼ 1.15 Hz, Ar-H), 7.00–6.99
(m, 1H, Ar-H), 6.96 (d, 1H, J ¼ 16.3 Hz), 6.89–6.87 (m, 1H, Ar-H),
6.36 (d, 1H, J ¼ 16.3 Hz), 3.81 (s, 3H, –OCH3). 13C (125 MHz,
CDCl3): d 159.3, 140.0, 135.2, 131.9, 129.4, 127.7, 124.2, 124.1,
122.5, 116.2, 115.0, 108.8, 92.3, 88.3, 55.2. IR (lm): 3008, 2938,
2190, 1580, 1460, 1324, 1218, 1073, 964, 807, 786 cmꢁ1. HRMS
(EI) calcd for C17H13BrO [M+] 312.0150; found 312ꢀ.0152.
13i. Yellow solid (0.076 g, 65%); m.p. 154–156 C, Rf ¼ 0.32
(hexane). 1H NMR (500 MHz, CDCl3): d 7.45 (d, 2H, J ¼ 8.55 Hz,
Ar-H), 7.40 (d, 2H, J ¼ 8.9 Hz, Ar-H), 7.26 (d, 2H, J ¼ 8.6 Hz,
Ar-H), 6.91 (d, 1H, J ¼ 16.05 Hz), 6.86 (d, 2H, J ¼ 8.9 Hz, Ar-H),
6.36 (d, 1H, J ¼ 16.35 Hz), 3.81 (s, 3H, –OCH3). 13C (125 MHz,
CDCl3): d 159.6, 139.0, 135.4, 133.0, 131.8, 127.6, 122.2, 115.3,
114.0, 109.2, 92.5, 87.3, 55.3. IR (lm): 2932, 2838, 2190, 1595,
1507, 1485, 1291, 1249, 1173, 1007, 955, 836, 807 cmꢁ1. HRMS
(EI) calcd for C17H13BrO [M+] 312.0150; found 312.0153.
IR (lm): 2923, 2852, 1587, 1488, 1095, 993, 828, 787 cmꢁ1
.
HRMS (EI) calcd for C16H10BrCl [M+] 315.9654; found 315.9656.
ꢀ
16a. Pale yellow solid (0.075 g, 59%); m.p. 186–188 C, Rf ¼
1
0.25 (hexane). H NMR (400 MHz, CDCl3): d 7.55–7.49 (m, 4H,
Ar-H), 7.40 (d, 4H, J ¼ 8.48 Hz, Ar-H), 7.36–7.30 (m, 5H, Ar-H),
7.02 (d, 1H, J ¼ 16.24 Hz), 6.39 (d, 1H, J ¼ 16.04 Hz). 13C (100
MHz, CDCl3): d 140.8, 135.9, 134.3, 132.7, 131.9, 131.6, 128.7,
128.3, 126.2, 123.5, 123.1, 121.8, 108.6, 91.4, 90.9, 89.8, 89.2. IR
(lm): 3081, 1913, 1488, 1441, 1397, 1099, 950, 833, 817, 754,
692 cmꢁ1. HRMS (EI) calcd for C24H15Cl [M+] 338.0862; found
338.0862.
16b. Yellow solid (0.071 g, 54%); m.p. 154–156 ꢀC, Rf ¼ 0.40
1
(EtOAc–hexane 1 : 99). H NMR (400 MHz, CDCl3): d 7.54–7.48
(m, 4H, Ar-H), 7.42–7.34 (m, 7H, Ar-H), 6.98 (d, 1H, J ¼ 16.52
Hz), 6.85 (d, 2H, J ¼ 8.72 Hz, Ar-H), 6.41 (d, 1H, J ¼ 16.04 Hz),
4.04 (q, 2H, J ¼ 7.02 Hz, –OCH2CH3), 1.42 (t, 3H, J ¼ 6.88 Hz,
–OCH2CH3). 13C (100 MHz, CDCl3): d 159.0, 139.5, 136.3, 133.0,
131.9, 131.6, 128.3, 126.1, 123.1, 123.0, 115.1, 114.5, 109.3, 92.9,
90.7, 89.3, 87.5, 63.5, 14.7. IR (lm): 2979, 1594, 1506, 1248,
ꢀ
13j. Pale yellow solid (0.091 g, 74%); m.p. 162–164 C, Rf ¼
0.36 (hexane). 1H NMR (500 MHz, CDCl3): d 7.45 (d, 2H, J ¼ 8.55
Hz, Ar-H), 7.39 (d, 2H, J ¼ 8.25 Hz, Ar-H), 7.26 (d, 2H, J ¼ 8.55
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1174, 1114, 1046, 946, 839, 816, 752 cmꢁ1. HRMS (EI) calcd for 1595, 1508, 953, 817, 786 cmꢁ1. HRMS (EI) calcd for C24H20 [M+]
C
26H20O [M+] 348.1514; found 348.1518.
16c. Pale yellow solid (0.050 g, 43%); m.p. 162–164 C, Rf ¼
308.1565; found 308.1562.
ꢀ
17c. Yellow solid (0.061 g, 48%); m.p. 200–202 ꢀC, Rf ¼ 0.45
1
1
0.27 (hexane). H NMR (400 MHz, CDCl3): d 7.53–7.48 (m, 4H, (EtOAc–hexane 2 : 98). H NMR (400 MHz, CDCl3): d 7.54–7.52
Ar-H), 7.39–7.23 (m, 7H, Ar-H), 7.02–6.97 (m, 2H, Ar-H), 6.39 (m, 4H, Ar-H), 7.46 (d, 2H, J ¼ 8.24 Hz, Ar-H), 7.38 (d, 2H, J ¼ 7.8
(d, 1H, J ¼ 16.48 Hz). 13C (100 MHz, CDCl3): d 140.3, 136.0, Hz, Ar-H), 7.14 (d, 2H, J ¼ 7.76 Hz, Ar-H), 7.05 (d, 1H, J ¼ 16.48
131.9, 131.6, 128.3, 127.4, 127.2, 126.2, 123.4, 123.1, 108.6, 92.7, Hz), 6.97 (d, 2H, J ¼ 8.68 Hz, Ar-H), 6.40 (d, 1H, J ¼ 16.48 Hz),
90.9, 89.3, 85.8. IR (lm): 3080, 1440, 1192, 962, 948, 815 cmꢁ1
.
4.08 (q, 2H, J ¼ 7.01 Hz, –OCH2CH3), 2.36 (s, 3H, CH3), 1.44
HRMS (EI) calcd for C22H14S [M+] 310.0816; found 310.0815.
(t, 3H, J ¼ 7.08 Hz, –OCH2CH3). 13C (100 MHz, CDCl3): d 158.7,
ꢀ
16d. Colourless solid (0.061 g, 51%); m.p. 128–130 C, Rf ¼ 140.9, 140.5, 138.3, 134.7, 132.7, 131.4, 129.1, 127.9, 126.8,
0.25 (hexane). 1H NMR (400 MHz, CDCl3): d 7.59 (br.s, 1H, Ar-H), 126.7, 120.3, 114.8, 107.8, 92.0, 88.4, 63.5, 21.5, 14.8. IR (lm):
7.57–7.54 (m, 2H, Ar-H), 7.45 (d, 1H, J ¼ 7.56 Hz, Ar-H), 2927, 2977, 1604, 1499, 1246, 821 cmꢁ1. HRMS (EI) calcd for
7.40–7.31 (m, 7H, Ar-H), 7.15 (d, 2H, J ¼ 8 Hz, Ar-H), 6.99 (d,
1H, J ¼ 16.24 Hz), 6.42 (d, 1H, J ¼ 16.28 Hz), 2.37 (s, 3H, –CH3).
C
25H22O [M+] 338.1671; found 338.1671.
18a. Yellow solid (0.062 g, 52%); m.p. 80–82 ꢀC, Rf ¼ 0.33
13C (100 MHz, CDCl3): d 139.8, 138.5, 136.6, 131.6, 131.4, 129.3, (EtOAc–hexane 1 : 99). 1H NMR (400 MHz, CDCl3): d 7.66 (d, 1H,
129.1, 128.7, 128.3, 126.0, 123.7, 123.0, 120.1, 109.2, 92.5, 89.7, J ¼ 15.8 Hz), 7.50 (d, 2H, J ¼ 8.28 Hz, Ar-H), 7.43 (d, 2H, J ¼ 8.48
88.9, 88.0, 21.5. IR (lm): 3024, 1598, 1508, 1491, 1441, 956, 817, Hz, Ar-H), 7.30–7.20 (m, 3H, Ar-H), 7.14 (d, 1H, J ¼ 7.56 Hz,
794, 754, 687 cmꢁ1. HRMS (EI) calcd for C25H18 [M+] 318.1409; Ar-H), 7.01 (d, 1H, J ¼ 16.24 Hz), 6.44 (d, 2H, J ¼ 15.36 Hz), 4.27
found 318.1407.
(q, 2H, J ¼ 7.17 Hz, –OCH2CH3), 2.34 (s, 3H, –CH3), 1.34 (t, 3H,
16e. Yellow solid (0.050 g, 38%); m.p. 168–170 ꢀC, Rf ¼ 0.32 J ¼ 7.1 Hz, –OCH2CH3). 13C (100 MHz, CDCl3): d 166.9, 143.7,
(EtOAc–hexane 2 : 98). 1H NMR (400 MHz, CDCl3): d 7.47 (d, 4H, 140.0, 138.2, 138.0, 134.5, 132.1, 129.3, 128.6, 128.4, 128.2, 126.6,
J ¼ 9.16 Hz, Ar-H), 7.39–7.36 (m, 4H, Ar-H), 7.14 (d, 2H, J ¼ 8.24 122.9, 118.3, 109.6, 93.1, 88.4, 60.5, 21.2, 14.3. IR (lm): 3029,
Hz, Ar-H), 6.99 (d, 1H, J ¼ 16 Hz), 6.89–6.86 (m, 2H, Ar-H), 6.39 2979, 1710, 1633, 1599, 1308, 1175, 1038, 957, 811, 784 cmꢁ1
.
(d, 1H, J ¼ 16.48 Hz), 3.83 (s, 3H, –OCH3), 2.36 (s, 3H, –CH3). 13
C
HRMS (EI) calcd for C22H20O2 [M+] 316.1463; found 316.1460.
(100 MHz, CDCl3): d 159.7, 140.1, 138.4, 135.9, 133.0, 131.7,
18b. Bright yellow solid (0.056 g, 47%); m.p. 122–124 ꢀC, Rf ¼
1
131.4, 129.1, 126.1, 123.6, 120.2, 115.2, 114.0, 108.9, 92.8, 90.8, 0.33 (EtOAc–hexane 1 : 99). H NMR (400 MHz, CDCl3): d 7.66
88.2, 88.1, 55.3, 21.5. IR (lm): 2921, 2212, 1605, 1508, 1246, (d, 1H, J ¼ 16.04 Hz), 7.49 (d, 2H, J ¼ 8.24 Hz, Ar-H), 7.42 (d, 2H,
833, 817 cmꢁ1. HRMS (EI) calcd for C26H20O [M+] 348.1514; J ¼ 8.2 Hz, Ar-H), 7.37 (d, 2H, J ¼ 8.24 Hz, Ar-H), 7.14 (d, 2H, J ¼
found 348.1528.
8.24 Hz, Ar-H), 7.00 (d, 1H, J ¼ 16 Hz), 6.43 (d, 2H, J ¼ 16.04 Hz),
16f. Bright yellow solid (0.040 g, 30%); m.p. 176–178 ꢀC, Rf ¼ 4.27 (q, 2H, J ¼ 7.17 Hz, –OCH2CH3), 2.36 (s, 3H, CH3), 1.34
0.30 (EtOAc–hexane 2 : 98). 1H NMR (400 MHz, CDCl3): d 7.53– (t, 3H, J ¼ 7.32 Hz, –OCH2CH3). 13C (100 MHz, CDCl3): d 166.9,
7.47 (m, 4H, Ar-H), 7.43–7.38 (m, 4H, Ar-H), 7.05 (t, 2H, J ¼ 8.82 143.8, 139.8, 138.6, 138.2, 134.5, 131.4, 129.1, 128.4, 126.6,
Hz, Ar-H), 6.98 (d, 1H, J ¼ 16.28 Hz), 6.87 (d, 2H, J ¼ 8.92 Hz, 120.1, 118.2, 109.7, 93.2, 88.1, 60.5, 21.5, 14.3. IR (lm): 2985,
Ar-H), 6.40 (d, 1H, J ¼ 16.28 Hz), 3.83 (s, 3H, –OCH3). 13C 1707, 1633, 1176, 963, 816 cmꢁ1. HRMS (EI) calcd for C22H20O2
(100 MHz, CDCl3): d 162.5 (d, J ¼ 251 Hz), 159.6, 139.5, 136.4, [M+] 316.1463; found 316.1461.
133.5 (d, J ¼ 7.67 Hz), 133.0, 131.8, 126.1, 122.9, 119.2, 115.6
18c. Bright yellow solid (0.060 g, 48%); m.p. 138–140 ꢀC, Rf ¼
1
(d, J ¼ 22.03 Hz), 115.3, 114.0, 109.3, 92.8, 89.6, 89.0, 87.6, 55.3. 0.18 (EtOAc–hexane 1 : 99). H NMR (400 MHz, CDCl3): d 7.66
IR (lm): 2923, 2851, 2189, 1597, 1508, 839, 816 cmꢁ1. HRMS (d, 1H, J ¼ 16.04 Hz), 7.49 (d, 2H, J ¼ 8.24 Hz, Ar-H), 7.41 (d, 4H,
(EI) calcd for C25H17FO [M+] 352.1263; found 352.1277.
J ¼ 8.92 Hz, Ar-H), 6.98 (d, 1H, J ¼ 16.04 Hz), 6.86 (d, 2H, J ¼ 8.92
ꢀ
17a. Pale yellow solid (0.060 g, 52%); m.p. 194–196 C, Rf ¼ Hz, Ar-H), 6.43 (d, 2H, J ¼ 16.04 Hz), 4.27 (q, 2H, J ¼ 7.1 Hz,
0.22 (hexane). 1H NMR (400 MHz, CDCl3): d 7.56 (d, 2H, J ¼ 8.24 –OCH2CH3), 3.82 (s, 3H, –OCH3), 1.34 (t, 3H, J ¼ 7.1 Hz,
Hz, Ar-H), 7.50–7.46 (m, 4H, Ar-H), 7.37 (d, 2H, J ¼ 8.28 Hz, Ar- –OCH2CH3). 13C (100 MHz, CDCl3): d 167.0, 159.7, 143.8, 139.3,
H), 7.25–7.23 (m, 2H, Ar-H), 7.13 (d, 2H, J ¼ 8 Hz, Ar-H), 7.04 138.3, 134.4, 133.0, 128.4, 126.6, 118.2, 115.3, 114.0, 109.8, 93.1,
(d, 1H, J ¼ 16.24 Hz), 6.40 (d, 1H, J ¼ 16 Hz), 2.39 (s, 3H, –CH3), 87.6, 60.5, 55.3, 14.3. IR (lm): 2936, 2189, 1708, 1629, 1507,
2.35 (s, 3H, –CH3). 13C (100 MHz, CDCl3): d 141.2, 140.4, 138.3, 1309, 1178, 1032, 836, 816 cmꢁ1. HRMS (EI) calcd for C22H20O3
137.5, 137.3, 135.1, 131.4, 129.5, 129.1, 127.1, 126.7, 126.6, [M+] 332.1412; found 332.1410.
120.3, 108.0, 92.1, 88.4, 21.5, 21.1. IR (lm): 2917, 1494, 1400,
18d. Yellow solid (0.053 g, 42%); m.p. 120–122 ꢀC, Rf ¼ 0.30
948, 803 cmꢁ1. HRMS (EI) calcd for C24H20 [M+] 308.1565; found (EtOAc–hexane 1 : 99). 1H NMR (400 MHz, CDCl3): d 7.66 (d, 1H,
308.1563.
J ¼ 16.04 Hz), 7.50 (d, 2H, J ¼ 8.48 Hz, Ar-H), 7.44–7.39 (m, 4H,
ꢀ
17b. Pale yellow solid (0.059 g, 51%); m.p. 108–110 C, Rf ¼ Ar-H), 7.31 (d, 2H, J ¼ 8.48 Hz, Ar-H), 7.02 (d, 1H, J ¼ 16.24 Hz),
0.26 (hexane). 1H NMR (400 MHz, CDCl3): d 7.61 (br.s, 1H, Ar-H), 6.44 (d, 1H, J ¼ 16.04 Hz), 6.41 (d, 1H, J ¼ 16.04 Hz), 4.27 (q, 2H,
7.51 (d, 3H, J ¼ 8.04 Hz, Ar-H), 7.41–7.39 (m, 4H, Ar-H), 7.28 J ¼ 7.18 Hz, –OCH2CH3), 1.34 (t, 3H, J ¼ 7.1 Hz, –OCH2CH3). 13
C
(d, 2H, J ¼ 7.8 Hz, Ar-H), 7.16 (d, 2H, J ¼ 7.8 Hz, Ar-H), 7.10 (d, (100 MHz, CDCl3): d 166.9, 143.7, 140.6, 138.0, 134.7, 134.3,
1H, J ¼ 16.04 Hz), 6.46 (d, 1H, J ¼ 16.04 Hz), 2.42 (s, 3H, –CH3), 132.7, 128.8, 128.7, 128.5, 126.7, 121.7, 118.4, 109.1, 91.7, 89.7,
2.38 (s, 3H, –CH3). 13C (100 MHz, CDCl3): d 141.6, 140.8, 138.3, 60.6, 14.3. IR (lm): 2981, 1712, 1636, 1489, 1263, 1093, 965,
137.9, 137.3, 136.8, 131.4, 129.5, 129.1, 127.2, 126.9, 124.9, 828 cmꢁ1. HRMS (EI) calcd for C21H17ClO2 [M+] 336.0917; found
124.7, 120.3, 108.6, 92.1, 88.2, 21.5, 21.1. IR (lm): 2920, 2190, 336.0915.
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C. S. Bryan and M. Lautens, Org. Lett., 2010, 12, 2754; (d)
M. Nagamochi, Y.-Q. Fang and M. Lautens, Org. Lett., 2007,
9, 2955; (e) J. Yuen, Y.-Q. Fang and M. Lautens, Org. Lett.,
2006, 8, 653.
8 F. Ramirez, N. B. Desai and N. Mckelvie, J. Am. Chem. Soc.,
1962, 84, 1745.
Acknowledgements
We thank Council of Scientic and Industrial Research (CSIR),
New Delhi for funding this work (no. 02(0091)/12/EMR-II). P.D.
and V.N.M. acknowledge CSIR for research fellowships.
9 S. Shimada and M. L. N. Rao, Top. Curr. Chem., 2012, 311,
199.
Notes and references
1 (a) Y. Segawa, T. Maekawa and K. Itami, Angew. Chem., Int.
Ed., 2015, 54, 66; (b) H. Xu, Y. Zhang, J. Huang and
W. Chen, Org. Lett., 2010, 12, 3704; (c) H. Xu, S. Gu,
W. Chen, D. Li and J. Dou, J. Org. Chem., 2011, 76, 2448.
2 (a) A. Coste, G. Karthikeyan, F. Couty and G. Evano, Angew.
Chem., Int. Ed., 2009, 48, 4381; (b) K. Jouvin, A. Coste,
A. Bayle, F. Legrand, G. Karthikeyan, K. Tadiparthi and
G. Evano, Organometallics, 2012, 31, 7933; (c) K. Jouvin,
A. Bayle, F. Legrand and G. Evano, Org. Lett., 2012, 14,
1652; (d) A. Coste, F. Couty and G. Evano, Org. Lett., 2009,
11, 4454; (e) G. Evano, K. Tadiparthi and F. Couty, Chem.
Commun., 2011, 47, 179.
3 (a) V. S. Batista, Science, 2009, 326, 245; (b) S. A. Haque and
J. Nelson, Science, 2010, 327, 1466, and references cited
therein; (c) Y. Liu, M. Nishiura, Y. Wang and Z. Hou, J. Am.
Chem. Soc., 2006, 128, 5592; (d) K. C. Nicolaou, W.-M. Dai,
S.-C. Tsay, V. A. Estevez and W. Wrasidlo, Science, 1992,
256, 1172.
10 (a) S. Shimada, O. Yamazaki, T. Tanaka, M. L. N. Rao,
Y. Suzuki and M. Tanaka, Angew. Chem., Int. Ed., 2003, 42,
1845; (b) M. L. N. Rao, S. Shimada and M. Tanaka, Org.
Lett., 1999, 1, 1271; (c) M. L. N. Rao, O. Yamazaki,
S. Shimada, T. Tanaka, Y. Suzuki and M. Tanaka, Org.
Lett., 2001, 3, 4103; (d) M. L. N. Rao, D. N. Jadhav and
P. Dasgupta, Org. Lett., 2010, 12, 2048.
11 E. Shirakawa, T. Kitabata, H. Otsuka and T. Tsuchimoto,
Tetrahedron, 2005, 61, 9878.
12 M. L. N. Rao, D. Banerjee and D. N. Jadhav, Tetrahedron Lett.,
2007, 48, 2707.
13 B. Ahmed-Omer, D. A. Barrow and T. Wirth, Tetrahedron
Lett., 2009, 50, 3352.
14 A. Sharma, B. P. Joshi and A. K. Sinha, Chem. Lett., 2003, 32,
1186.
15 G. Rai, C. J. Thomas, W. Leister and D. J. Maloney,
Tetrahedron Lett., 2009, 50, 1710.
16 I. N. Michaelides, B. Darses and D. J. Dixon, Org. Lett., 2011,
13, 664.
4 Y. I. Park, O. Postupna, A. Zhugayevych, H. Shin, Y.-S. Park,
B. Kim, H.-J. Yen, P. Cheruku, J. S. Martinez, J. W. Park,
S. Tretiak and H.-L. Wang, Chem. Sci., 2015, 6, 789.
5 (a) G. Chelucci, F. Capitta and S. Baldino, Tetrahedron, 2008,
64, 10250; (b) A. Rahimi and A. Schmidt, Synthesis, 2010,
2621; (c) H. Yan, L. Lu, P. Sun, Y. Zhu, H. Yang, D. Liu,
G. Rong and J. Mao, RSC Adv., 2013, 3, 377.
´
17 E. Metay, Q. Hu and E. Negishi, Org. Lett., 2006, 8, 5773.
18 Y. Zhu, T. Li, X. Qu, P. Sun, H. Yang and J. Mao, Org. Biomol.
Chem., 2011, 9, 7309.
19 Y. Liu, J. Yang and W. Bao, Eur. J. Org. Chem., 2009, 5317.
20 X. Xie, X. Xu, H. Li, X. Xu, J. Yang and Y. Li, Adv. Synth. Catal.,
2009, 351, 1263.
6 (a) E. Ruijter, R. Scheffelaar and R. V. A. Orru, Angew. Chem.,
Int. Ed., 2011, 50, 6234; (b) B. M. Trost, Angew. Chem., Int. Ed.,
1995, 34, 259; (c) L. F. Tietze, Chem. Rev., 1996, 96, 115.
7 (a) G. Chelucci, Chem. Rev., 2012, 112, 1344; (b) N. Nicolaus,
P. T. Franke and M. Lautens, Org. Lett., 2011, 13, 4236; (c)
21 R. A. Aitken, C. Boeters and J. J. Morrison, J. Chem. Soc.,
Perkin Trans. 1, 1994, 2473.
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