Sequential one-pot approach for the synthesis of functionalized phthalans via Heck-reduction-cyclization (HRC) reactions

Article abstract of DOI:10.1039/c5ra00955c

An efficient and practical method is described for the direct synthesis of 1,3-dihydroisobenzofurans, an important structural motif present in biologically active natural or synthetic compounds. The reaction was performed in an almost one-pot fashion via

Full text of DOI:10.1039/c5ra00955c

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Sequential one-pot approach for the synthesis of
functionalized phthalans via Heck-reduction–
cyclization (HRC) reactions†
Cite this: RSC Adv., 2015, 5, 26749
*
Jonnada Krishna, Pedireddi Niharika and Gedu Satyanarayana
An efficient and practical method is described for the direct synthesis of 1,3-dihydroisobenzofurans, an
important structural motif present in biologically active natural or synthetic compounds. The reaction
was performed in an almost one-pot fashion via controlled [Pd]-catalyzed intermolecular Mizoroki–Heck
coupling between 2-bromobenzaldehydes and allylic alcohols followed by reduction and treatment of
crude diol with a Lewis acid to give 1,3-dihydroisobenzofurans. Significantly, the method enabled the
synthesis of 1,3-dihydroisobenzofurans with simple to dense functionalities on the aromatic rings.
Received 16th January 2015
Accepted 25th February 2015
DOI: 10.1039/c5ra00955c
www.rsc.org/advances
our interest in the development of synthetic methods by [Pd]-
catalysis,13 we have observed the selective formation of b-aryl
Introduction
allylic alcohols 3 in a highly regio- and stereo-selective man-
ner.13b Surprisingly, this is not the expected product 3 under
conventional Jeffery-Heck conditions. Aer a careful study of
the literature, we realized that the usual Heck reaction followed
by double bond isomerization to give the carbonyl compounds
was observed for those substrates having no ortho-substituents
on the aromatic ring of the allylic alcohols.14 Therefore, it was
thought that the bromo substituent at the ortho-position on the
aromatic moiety of the allylic alcohol plays a major role to
conne the rotation around C–C bond of the PdCH–CH(OH)Ar
intermediate (Scheme 1).
Amongst the b-aryl allylic alcohols 3, those with aldehyde
functionality on the aromatic ring appear to be a potential
synthetic precursor for the synthesis of oxygen containing
heterocyclic compounds (i.e., R3 ¼ CHO and X ¼ Br). Therefore,
herein, we report a short and efficient synthesis of interesting
Development of new synthetic methods based on one-pot
synthesis or sequential one-pot synthesis are considered as
important methods for the synthesis of organic compounds.1
Particularly, the sequential one-pot processes involved in
multiple reactions are promoted by a metal-catalyst in a
sequential fashion.2 Moreover, such transformations could also
be feasible via the sequential addition of reagents to accomplish
a set of reactions.3 In addition, it would also be possible to
develop such one-pot methods using a metal-catalyst to
complete the initial reaction followed by the treatment of the
resultant intermediate product with a reagent or vice versa.4
These types of processes can be classied into pseudo-domino,
cascade5 and tandem-processes. Usually, the one-pot methods
have certain advantages over conventional methods. For
example, they reduce waste formation, save time, energy,
resources and increase the efficacy.6 In general, the overall
yields of such processes are found to be higher than those from
the corresponding step-wise methods. Thus, the sequential one-
pot processes that construct multiple bonds are of immense
importance, particularly for the synthesis of cyclic structures
because many cyclic systems constitute core or part-structures
of biologically active natural or synthetic compounds.
cyclic ethers 1,3-dihydroisobenzofurans
6 by employing
Recently, transition-metal mediated one-pot processes have
gained considerable attention due to their procedural advan-
tages.7,8 Among them, the domino Heck reactions under [Pd]-
catalysis are well known,9–11 although the reports on Heck
coupling followed by reduction are limited.12 In continuation of
Department of Chemistry, Indian Institute of Technology (IIT), Hyderabad, Ordnance
Factory Estate Campus, Yeddumailaram – 502 205, Medak District, Telangana, India.
E-mail: gvsatya@iith.ac.in; Fax: +91 40 2301 6032; Tel: +91 40 2301 6054
† Electronic supplementary information (ESI) available. See DOI:
10.1039/c5ra00955c
Scheme 1 Synthesis of b-aryl allylic alcohols 3.
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reduction and acid mediated intramolecular cyclization
protocol on b-aryl allylic alcohols 3.
Oxygen containing heterocyclic compounds are widely
assayed for their substantial therapeutic applications such as
tetrahydroisobenzofuran motifs.15,16 They are pervasive struc-
tural elements in biologically relevant small molecules (Fig. 1).
For example, 3-deoxyisochracinic acid 8 that was isolated from
Cladosporium species shows antibacterial activity by inhibiting
the growth of Bacillus subtilis.15a The cyclic ether pestacin 9 was
obtained from microorganism Pestalotiopsis microspora, which
exhibits antifungal, antimycotic and antioxidant activities.15b FR
198248 10 was isolated from Aspergillus avipes, which shows
antibacterial activity and inhibitory activity against Staphylo-
coccus aureus peptide deformylase and also exhibits anti-
inuenza activity.15c–e 1,4-Dimethoxy-3-(3R-hydroxy-3R-methyl-
1-tetralone)-1(3H)-isobenzofuran 11 was isolated from the broth
of marine Streptomyces species M268 and identied to be cyto-
toxic against human cancer cell lines HL-60, A549 and
BEL-7402.15f 7-Bromo-1-(2,3-dibromo-4,5-dihydroxyphenyl)-5,6-
dihydroxy-1,3-dihydroisobenzofuran 12 was isolated from a
brown alga Leathesia nana, and it shows potential action on
malignant tumors and cardiovascular diseases.15g The (S)-
(+)-enantiomer 13, known as escitalopram, seems to be more
potent than the other (S)-(ꢀ)-enantiomer.15h–l
Scheme 2 Synthesis of diol 5.
conditions, and the results are summarized in Table 1. Thus,
the reaction carried out with a Lewis acid (BF3$Et2O) at 0 ꢁC, as
well as at ꢀ10 ꢁC, leads to the decomposition of the starting
material (Table 1, entries 1 and 2). Therefore, the reaction at a
further low temperature (ꢀ20 ꢁC), furnished the product 6ca in
poor yield (30%, Table 1, entry 3). Interestingly, a further drop of
temperature (ꢀ40 ꢁC) gave the product 6ca in excellent yield
(95%, Table 1, entry 4). However, exploring the reaction with
different acids such as protic acid (p-TSA) or Lewis acid (AlCl3)
furnished the product 6ca in moderate to very good yields
(Table 1, entries 5–7), whereas the reaction with H2SO4 gave the
product in poor yield (20%, Table 1, entries 8).
Having established the reaction conditions for the synthesis
of 1,3-dihydroisobenzofuran 6, we thought that the method can
still be made more efficient by performing cyclization directly
on crude diol 5ca without the column purication. Interest-
ingly, the reaction was found to be smooth on the crude diol 5ca
(i.e., the crude diol, which was obtained aer work-up followed
by concentration under reduced pressure) and furnished the
product in the overall yield of 48% (Scheme 3). The structure of
the cyclic ether 6ca was conrmed from the spectroscopic data.
1H-NMR data unambiguously conrmed the geometry of the
double bond as trans by calculating the coupling constant (J ¼
15.5 to 15.6 Hz, see Experimental section and ESI†). Therefore,
the other possibility for the formation of seven membered cyclic
ether 7ca was ruled out because it must contain a cis double
bond. In addition, the formation of ve membered cyclic ether
6ca is geometrically favoured over the seven membered one.
Now, with the optimized reaction conditions in hand, to
check the scope and limitations of the method, we investigated
this sequential one-pot method on various 2-bromobenzalde-
hydes 1a–1g in conjunction with ortho-bromo aryl allylic alco-
hols 2a–2h. Quite interestingly, the method was amenable on
various systems possessing dense functionalities on both the
aromatic rings and furnished the products 6aa–6gg in moderate
yields (41–55%), as summarized in Fig. 2. It is worth
mentioning that although the yields of the cyclic ether products
6 are moderate, they actually represent the overall yield of three
individual reactions. Therefore, each step contributes to at least
75% yield, and thus the method still stands efficient.
We thought that the process can be made more efficient by
developing a sequential one-pot method for the direct synthesis
of diol 5 starting from aryl allylic alcohols 2 and 2-bromo-
benzaldehydes 1. This can be achieved by [Pd]-catalysed
coupling for the formation of b-aryl allylic alcohols 3 and in
situ reduction of the aldehyde functionality. Thus, the [Pd]-
catalyzed coupling of 2-bromobenzaldehyde 1c with ortho-
bromo aryl allylic alcohol 1a followed by the reduction of 3ca
with NaBH4 gave the desired diol 5ca in a very good yield
(Scheme 2). The idea behind this hypothesis is to minimize the
number of steps and waste and to improve the overall yield of
the reaction over the step-wise approach. However, the diol 5ca
was not characterized due to its insolubility in CDCl3, and
hence it proceeded to the next reaction.
With the required diol 5ca in hand, the acid promoted
cyclization was subsequently explored under different sets of
Aer the successful synthesis of 1,3-dihydroisobenzofurans,
we planned to increase the scope of this protocol by employing
the allylic alcohols possessing a methyl/methoxy group in the
ortho position. During the sequential one-pot approach, we
observed the formation of the regular Jeffery-Heck product
Fig. 1 Representative examples of naturally occurring phthalans.
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Table 1 Optimization table for the synthesis of 1,3-dihydroisobenzofuran 6ca from the diol 5ca
Entrya
Acid (equiv)
Solvent (5 mL)
Temp (ꢁC)
Time min
Yieldb of 6ca (%)
1
2
3
4
5
6
7
8
BF3$Et2O (2.0)
BF3$Et2O (4.0)
BF3$Et2O (5.0)
BF3$Et2O (5.0)
p-TSA (3.0)
AlCl3 (1.2)
AlCl3 (1.2)
H2SO4 (3.0)
DCM
DCM
DCM
DCM
DCM
DCM
DCE
0
ꢀ10
ꢀ20
ꢀ40
ꢀ40
ꢀ40
ꢀ40
ꢀ40
15
15
15
120
60
10
—
—
30
95
50
70
80
20
10
30
DCM
a
b
Reaction conditions: all the reactions carried out with diol 5ca (0.10 mmol) in DCM. Isolated yields of chromatographically pure products.
standard fashion with reference to either internal standard
tetramethylsilane (TMS) (dH ¼ 0.00 ppm) or CHCl3 (dH
¼
7.25 ppm). 13C-NMR spectra were recorded on a Bruker Avance
400 (100 MHz) spectrometer at 295 K in CDCl3; chemical shis
(d in ppm) are reported relative to CHCl3 [dC ¼ 77.00 ppm
(central line of triplet)]. In 13C-NMR, the nature of carbons
(namely, C, CH, CH2 and CH3) was determined by recording the
DEPT-135 spectra, and it is given in parentheses and noted as
s ¼ singlet (for C), d ¼ doublet (for CH), t ¼ triplet (for CH2) and
1
q ¼ quartet (for CH3). In H-NMR, the following abbreviations
were used throughout: s ¼ singlet, d ¼ doublet, t ¼ triplet,
q ¼ quartet, qui ¼ quintet, m ¼ multiplet and br. s ¼ broad
singlet, septd ¼ septet of doublets. The assignment of signals
was conrmed by 1H, 13C CPD and DEPT spectra. High-
resolution mass spectra (HR-MS) were recorded on an Agilent
6538 UHD Q-TOF using multimode source. X-ray crystal struc-
ture data were obtained using an Oxford Super Nova instru-
ment. All the small scale dry reactions were carried out using
the standard syringe-septum technique. Reactions were moni-
tored by TLC on silica gel using a mixture of petroleum ether
and ethyl acetate as eluents. Reactions were generally run under
an argon or nitrogen atmosphere. All the solvents were distilled
prior to use; petroleum ether with a boiling range of 60 to 80 ꢁC,
diethyl ether, dichloromethane (DCM), ethyl acetate, THF (with
purity 99%), and acetonitrile (with purity 99.9%), which were
purchased from locally available commercial sources were used.
All aromatic aldehydes (with purity 98%), bromine (with purity
99%), iodine (with purity 99%), Bn(Et)3NCl (with purity 99%),
Pd(OAc)2 (with purity 98%), 3-iodoanisole (with purity 99%),
2-bromoiodobenzene (with purity 99%), NaBH4 (with purity
99%), K2CO3 (with purity 99%), and NaHCO3 (with purity
99.5%) were purchased from Sigma-Aldrich, whereas vinyl-
magnesium bromide (with purity 99%), BF3$Et2O (with purity
48%) and iodobenzene (with purity 99%) were purchased from
Scheme 3 Sequential one-pot method for the synthesis of 6ca.
along with the Mizoroki–Heck product.13b This (Jeffery-Heck
product) interfered in the further steps and hindered the
isolation of clean products. Thus, we proceeded in a step-wise
approach and achieved the targeted 1,3-dihydroisobenzofur-
ans 6ai and 6aj in a moderate overall yield (47% and 52%). It is
worth mentioning that in these cases, we were also able to
characterise diol 5 (Scheme 4).
Experimental section
General considerations
IR spectra were recorded on a Bruker Tensor 37 (FT-IR) spec-
trophotometer. 1H-NMR spectra were recorded on a Bruker
Avance 400 (400 MHz) spectrometer at 295 K in CDCl3; chemical
shis (d in ppm) and coupling constants (J in Hz) are reported in
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Fig. 2 Synthesis of 1,3-dihydroisobenzofurans 6aa–6gg from 2-bromobenzaldehydes 1a–1g and aryl allylic alcohols 2a–2h. All reactions were
carried out with 2-bromobenzaldehydes 1a–1g (0.50 mmol). Isolated yields of chromatographically pure products in parentheses.
other commercial sources and used as received. The base over P2O5. Acme's silica gel (60–120 mesh) was used for column
NaHCO3 was dried at 150–170 ꢁC over an oil bath. Diethyl ether chromatography (approximately 20 g per one gram of crude
and toluene were dried over sodium/benzophenone, DCM and material).
DCE were dried over calcium hydride, and acetonitrile was dried
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stirred for 2 h at the same temperature. The reaction mixture
was then quenched with saturated aqueous NaHCO3 solution,
and the aqueous layer was extracted with DCM (3 ꢂ 20 mL). The
organic layers were dried over anhydrous Na2SO4, ltered, and
concentrated under reduced pressure. Purication of the
residue on a silica gel column chromatography (petroleum
ether/ethyl acetate) furnished the product 6aa–6gg (40–55%).
General procedure-3 for the synthesis of 1,3-dihy-
droisobenzofurans (6ai and 6aj). In an oven-dried Schlenk ask
under nitrogen atmosphere, Pd(OAc)2 (5 mol%), Bn(Et)3NCl
(0.50 mmol), NaHCO3 (1 mmol), 2-bromobenzaldehydes 1a
(0.50 mmol) and ortho-bromo aryl allylic alcohol 2i–2j (0.60
mmol) were added, followed by the addition of dry acetonitrile
(4 mL). The resulting reaction mixture was stirred for 24 h at
ꢁ
80 C. The reaction mixture was quenched using saturated aq.
NH4Cl solution, and then compound was extracted in ethyl
acetate and concentrated under reduced pressure. The aldehyde
3 was isolated by silica gel column chromatography (petroleum
ether/ethyl acetate). The aldehyde 3 was cooled to 0 ꢁC and
NaBH4 (1.50 mmol) was added and stirred for two hours at
room temperature. The reaction mixture was quenched with
saturated aq. NH4Cl solution and extracted with ethyl acetate
(3 ꢂ 20 mL). The organic layer was washed with saturated NaCl
solution, dried over anhydrous Na2SO4 and concentrated under
reduced pressure. Traces of solvents were removed under high
vacuum, and to the obtained crude, 20 mL of dry DCM was
Scheme
4 Step-wise approach for the synthesis of 1,3-dihy-
droisobenzofurans 6ai and 6aj from 2-bromobenzaldehyde 1a and aryl
allylic alcohols 2i and 2j.
ortho-Bromobenzaldehydes 1a–1h except 1a were synthe-
sized from corresponding aromatic aldehydes using a bromi-
nation method reported in the literature.17 Among the bromo
aryl allylic alcohols, 2a,18 2g13b and 2h13b were reported in
literature.
General procedure-1 for the synthesis of ortho-bromo aryl
allylic alcohols (2a–2h). To a magnetically stirred solution of 2-
bromobenzaldehydes 1aꢁ–1h (10 mmol) in THF (20 mL), in a
round bottom ask at 0 C, under nitrogen atmosphere, 1.0 M
of vinylmagnesium bromide (20 mmol, 1.0 M in THF) was
added, and the resultant reaction mixture was slowly allowed to
reach room temperature and stirred for 1.5 h. The reaction
mixture was quenched with saturated aq. NH4Cl solution and
extracted with diethyl ether (3 ꢂ 30 mL). The organic layer was
washed with saturated NaCl solution, dried over anhydrous
Na2SO4 and concentrated under reduced pressure. Purication
of the residue on a silica gel column chromatography (petro-
leum ether/ethyl acetate 90 : 10 to 80 : 20) furnished ortho-
bromo aryl allylic alcohols 2a–2h (80–92%).
ꢁ
added, and then the mixture was cooled to ꢀ40 C, BF3$Et2O
(2.5 mmol) was added, and the reaction mixture was stirred for
2 h at the same temperature. The reaction mixture was then
quenched with saturated aqueous NaHCO3 solution and the
aqueous layer was extracted with DCM (3 ꢂ 20 mL). The organic
layers were dried over anhydrous Na2SO4, ltered, and
concentrated under reduced pressure. Purication of the
residue on a silica gel column chromatography (petroleum
ether/ethyl acetate) furnished the products 6ai & 6aj (47–52%).
1-[5-(Benzyloxy)-2-bromophenyl]prop-2-en-1-ol (2b). GP-1 was
carried out and the product 2b (2.80 g, 88%) was furnished as a
pale yellow liquid. [TLC control Rf(1b) ¼ 0.60, Rf(2b) ¼ 0.40
(petroleum ether/ethyl acetate 90 : 10, UV detection)]. IR (MIR-
ATR, 4000–600 cmꢀ1): nmax ¼ 3371, 3032, 2920, 1592, 1571,
1462, 1291, 1380, 1291, 1233, 1163, 1010, 927, 736, 697 cmꢀ1. 1H
NMR (CDCl3, 400 MHz): d ¼ 7.50–7.28 (m, 6H, Ar-H), 7.19 (d,
1H, J ¼ 2.9 Hz, Ar-H), 6.78 (dd, 1H, J ¼ 8.8 and 2.9 Hz, Ar-H), 5.99
(ddd, 1H, J ¼ 15.6, 10.3 and 5.4 Hz, CH]CH2), 5.54 (d, 1H, J ¼
5.4 Hz, ArCH–OH), 5.40 (td, 1H, J ¼ 15.6 and 1.5 Hz, C]CHaHb),
5.22 (td, 1H, J ¼ 10.3 and 1.5 Hz, C]CHaHb), 5.04 (s, 2H,
PhCH2O), 2.25 (d, 1H, J ¼ 3.9 Hz, OH) ppm. 13C NMR (CDCl3,
100 MHz): d ¼ 158.4 (s, Ar-C), 142.5 (s, Ar-C), 138.1 (d,
CH]CH2), 136.4 (s, Ar-C), 133.3 (d, Ar-CH), 128.6 (d, 2C, Ar-CH),
128.1 (d, Ar-CH), 127.5 (d, 2C, Ar-CH), 115.9 (d, Ar-CH), 115.7 (t,
CH]CH2), 114.2 (d, Ar-CH), 112.9 (s, Ar-C), 73.4 (d, Ar-CHOH),
70.2 (t, PhCH2) ppm. HR-MS (ESI+) m/z calculated for
[C16H14BrO]+ ¼ [(M + H)–H2O]+: 301.0223; found 301.0213.
1-(2-Bromo-5-methoxyphenyl)prop-2-en-1-ol (2c). GP-1 was
carried out and the product 2c (2.20 mg, 92%) was furnished as
a pale yellow liquid. [TLC control Rf(1c) ¼ 0.80, Rf(2c) ¼ 0.50
(petroleum ether/ethyl acetate 80 : 20, UV detection)]. IR
General procedure-2 for the synthesis of 1,3-dihy-
droisobenzofurans (6aa–6gg). In an oven-dried Schlenk ask
under nitrogen atmosphere, Pd(OAc)2 (5 mol%), Bn(Et)3NCl
(0.50 mmol), NaHCO3 (1 mmol), 2-bromobenzaldehydes 1a–1g
(0.50 mmol) and ortho-bromo aryl allylic alcohol 2a–2h (0.60
mmol) were added, followed by the addition of dry acetonitrile
(4 mL). The resulting reaction mixture was stirred for 24 h at
80 ꢁC. Then, the reaction mixture was cooled to 0 ꢁC and NaBH4
(1.50 mmol) was added to it, and the mixture was stirred for two
hours at room temperature. The reaction mixture was quenched
with saturated aq. NH4Cl solution and extracted with ethyl
acetate (3 ꢂ 20 mL). The organic layer was washed with satu-
rated NaCl solution, dried over anhydrous Na2SO4 and
concentrated under reduced pressure. Traces of solvents were
removed under high vacuum, and to the obtained crude, 20 mL
of dry DCM was added, and then the mixture was cooled to
ꢁ
ꢀ40 C, BF3$Et2O (2.5 mmol) was added, and the reaction was
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(MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 3380, 2922, 2851, 1593, 1572, (petroleum ether/ethyl acetate 80 : 20, UV detection)]. IR (MIR-
1468, 1416, 1290, 1233, 1161, 1047, 1013, 928, 807, 771 cmꢀ1. 1H ATR, 4000–600 cmꢀ1): nmax ¼ 3346, 2897, 1501, 1471, 1407,
NMR (CDCl3, 400 MHz): d ¼ 7.39 (d, 1H, J ¼ 8.8 Hz, Ar-H), 7.07 1230, 1107, 1035, 930, 840, 798 cmꢀ1
.
1H NMR (CDCl3, 400
(d, 1H, J ¼ 3.4 Hz, Ar-H), 6.69 (dd, 1H, J ¼ 8.8 and 3.4 Hz, Ar-H), MHz): d ¼ 6.98 (s, 1H, Ar-H), 6.96 (s, 1H, Ar-H), 5.95 (d, 1H, J ¼
5.99 (ddd, 1H, J ¼ 17.1, 10.3 and 5.4 Hz, CH]CH2), 5.53 (d, 1H, 5.4 Hz, OCHaHbO), 5.94 (d, 1H, J ¼ 5.4 Hz, OCHaHbO), 5.93 (ddd,
J ¼ 5.4 Hz, ArCH–OH), 5.38 (td, 1H, J ¼ 17.1 and 1.5 Hz, 1H, J ¼ 15.6, 10.3 and 5.4 Hz, CH]CH2), 5.51 (d, 1H, J ¼ 5.4 Hz,
C]CHaHb), 5.21 (dd, 1H, J ¼ 10.3 and 1.5 Hz, C]CHaHb), 3.78 ArCH–OH), 5.37 (td, 1H, J ¼ 15.6 and 1.5 Hz, C]CHaHb), 5.20
(s, 3H, Ar-OCH3), 2.34 (br. s, 1H, OH) ppm. 13C NMR (CDCl3, 100 (td, 1H, J ¼ 10.3 and 1.5 Hz, C]CHaHb), 2.26 (d, 1H, J ¼ 2.9 Hz,
MHz): d ¼ 159.3 (s, Ar-C), 142.4 (s, Ar-C), 138.1 (d, CH]CH2), OH) ppm. 13C NMR (CDCl3, 100 MHz): d ¼ 147.8 (s, Ar-C), 147.7
133.3 (d, Ar-CH), 115.7 (t, CH]CH2), 115.2 (d, Ar-CH), 113.0 (d, (s, Ar-C), 138.4 (d, CH]CH2), 134.8 (s, Ar-C), 115.3 (t,
Ar-CH), 112.7 (s, Ar-C), 73.4 (d, Ar-CHOH), 55.4 (q, Ar-OCH3) CH]CH2), 112.8 (s, Ar-C), 112.5 (d, Ar-CH), 107.7 (d, Ar-CH), 101.7
ppm. HR-MS (ESI+) m/z calculated for [C10H10BrO]+ ¼ [(M + H)– (t, OCH2O), 73.3 (d, Ar-CHOH) ppm. HR-MS (ESI+) m/z calculated
H2O]+: 224.9910; found 224.9903.
1-[5-(Benzyloxy)-2-bromo-4-methoxyphenyl]prop-2-en-1-ol (2d).
for [C10H9BrNaO3]+ ¼ [M + Na]+: 278.9627; found 278.9639.
1-[(E)-2-(2-Bromophenyl)vinyl]-1,3-dihydro-2-benzofuran (6aa).
GP-1 was carried out and the product 2d (2.96 g, 85%) was GP-2 was carried out and the product 6aa (83 mg, 55%) was
furnished as a brownish viscous liquid. [TLC control Rf(1d) ¼ furnished as a yellow viscous liquid. [TLC control Rf(1a) ¼ 0.80,
0.60, Rf(2d) ¼ 0.30 (petroleum ether/ethyl acetate 90 : 10, UV Rf(2a) ¼ 0.70 and Rf(6aa) ¼ 0.85 (petroleum ether/ethyl acetate
detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 3392, 2933, 95 : 5, UV detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax
¼
2847, 1599, 1497, 1454, 1381, 1251, 1120, 1155, 1120, 1039, 2922, 2852, 1588, 1465, 1437, 1357, 1284, 1246, 1158, 1122,
1023, 861, 834, 696, 665 cmꢀ1 1H NMR (CDCl3, 400 MHz): 1107, 1021, 963, 747, 698, 665 cmꢀ1. 1H-NMR (CDCl3, 400 MHz):
.
d ¼ 7.42 (dd, 2H, J ¼ 7.3 and 6.8 Hz, Ar-H), 7.37 (t, 2H, J ¼ 7.3 Hz, d ¼ 7.53 (dd, 1H, J ¼ 7.8 and 1.5 Hz, Ar-H), 7.50 (dd, 1H, J ¼ 7.8
Ar-H), 7.31 (ddd, 1H, J ¼ 7.3 and 6.8 Hz, Ar-H), 7.03 (s, 1H, Ar-H), and 1.5 Hz, Ar-H), 7.35–7.15 (m, 5H, Ar-H), 7.10 (d, 1H, J ¼ 15.6
7.02 (s, 1H, Ar-H), 5.98 (ddd, 1H, J ¼ 15.6, 10.3 and 4.9 Hz, Hz, ArCH]CH), 7.08 (ddd, 1H, J ¼ 9.3, 7.8 and 1.5 Hz, Ar-H),
CH]CH2), 5.51 (d, 1H, J ¼ 5.4 Hz, ArCH–OH), 5.38 (td, 1H, J ¼ 6.21 (dd, 1H, J ¼ 15.6 and 7.8 Hz, ArCH]CH), 5.80 [d, 1H, J ¼
15.6 and 1.5 Hz, C]CHaHb), 5.20 (td, 1H, J ¼ 10.3 and 1.5 Hz, 7.8 Hz, PhCH(O)CH]CH], 5.22 (d, 1H, J ¼ 11.7 Hz, PhCHaHb-
C]CHaHb), 5.09 (s, 2H, PhCH2O), 3.38 (s, 3H, Ar-OCH3), 2.29 (d, OCHCH]CH), 5.14 (d, 1H, J ¼ 11.7 Hz, PhCHaHbOCHCH]CH)
1H, J ¼ 2.9 Hz, OH) ppm. 13C NMR (CDCl3, 100 MHz): d ¼ 149.4 ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 140.6 (s, Ar-C), 139.1 (s, Ar-
(s, Ar-C), 148.1 (s, Ar-C), 138.5 (d, CH]CH2), 136.3 (s, Ar-C), C), 136.4 (s, Ar-C), 132.9 (d, Ar-CH), 132.0 (d, Ar-CH), 130.5 (d, Ar-
134.0 (s, Ar-C), 128.6 (d, 2C, Ar-CH), 128.0 (d, Ar-CH), 127.3 (d, CH–CH]CH-Ar), 129.1 (d, Ar-CH–CH]CH-Ar), 127.8 (d, Ar-CH),
2C, Ar-CH), 117.6 (d, Ar-CH), 115.3 (t, CH]CH2), 112.1 (s, Ar-C), 127.5 (d, Ar-CH), 127.4 (d, Ar-CH), 127.3 (d, Ar-CH), 123.8 (s, Ar-
110.7 (d, Ar-CH), 73.3 (d, Ar-CHOH), 71.2 (t, PhCH2), 56.0 (q, Ar- C), 122.0 (d, Ar-CH), 121.1 (d, Ar-CH), 85.0 (d, Ph-CHCH]CH),
OCH3) ppm. HR-MS (ESI+) m/z calculated for [C17H16BrO2]+ ¼ 72.9 (t, Ph-CH2OCHCH]CH) ppm. HR-MS (ESI+): m/z calculated
[(M + H)–H2O]+: 331.0328; found 331.0332.
1-[4-(Benzyloxy)-2-bromo-5-methoxyphenyl]prop-2-en-1-ol (2e).
for [C16H13BrNaO]+ ¼ [M + Na]+: 323.0042; found 323.0041.
1-{(E)-2-[5-(Benzyloxy)-2-bromophenyl]vinyl}-1,3-dihydro-2-
GP-1 was carried out and the product 2e (2.79 g, 80%) was benzofuran (6ab). GP-2 was carried out and the product 6ab
furnished as a brownish viscous liquid. [TLC control Rf(1e) ¼ (92 mg, 45%) was furnished as a pale yellow viscous liquid. [TLC
0.60, Rf(2e) ¼ 0.30 (petroleum ether/ethyl acetate 90 : 10, UV control (petroleum ether/ethyl acetate 95 : 5, Rf(1a) ¼ 0.80,
detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 3404, 3032, Rf(2b) ¼ 0.50 and Rf(6ab) ¼ 0.65 UV detection)]. IR (MIR-ATR,
3008, 2932, 1600, 1502, 1502, 1439, 1379, 1257, 1156, 1120, 4000–600 cmꢀ1): nmax ¼ 2922, 2852, 1590, 1563, 1459, 1286,
1029, 925, 863, 777 cmꢀ1. 1H NMR (CDCl3, 400 MHz): d ¼ 7.42 1238, 1173, 1028, 1013, 963, 739, 697 cmꢀ1. 1H-NMR (CDCl3, 400
(d, 2H, J ¼ 7.3 Hz, Ar-H), 7.35 (dd, 2H, J ¼ 7.3 and 6.8 Hz, Ar-H), MHz): d ¼ 7.41 (d, 1H, J ¼ 8.3 Hz, Ar-H), 7.39–7.20 (m, 8H, Ar-H),
7.29 (t, 1H, J ¼ 7.3 Hz, Ar-H), 7.06 (s, 1H, Ar-H), 7.00 (s, 1H, Ar- 7.19 (dd, 1H, J ¼ 8.3 and 2.4 Hz, Ar-H), 7.14 (d, 1H, J ¼ 2.9 Hz,
H), 5.90 (ddd, 1H, J ¼ 15.6, 10.3 and 4.9 Hz, CH]CH2), 5.49 (d, Ar-H), 7.05 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.73 (dd, 1H, J ¼ 8.8
1H, J ¼ 5.4 Hz, ArCH–OH), 5.35 (td, 1H, J ¼ 15.6 and 1.5 Hz, and 2.9 Hz, Ar-H), 6.19 (dd, 1H, J ¼ 15.6 and 7.3 Hz, ArCH]CH),
C]CHaHb), 5.31 (td, 1H, J ¼ 10.3 and 1.5 Hz, C]CHaHb), 5.11 5.80 [d, 1H, J ¼ 7.3 Hz, PhCH(O)CH]CH], 5.22 (dd, 1H, J ¼ 12.2
(d, 1H, J ¼ 12.2 Hz, PhCHaHbO), 5.10 (d, 1H, J ¼ 12.2 Hz, and 2.4 Hz, PhCHaHbOCHCH]CH), 5.13 (dd, 1H, J ¼ 12.2 and
PhCHaHbO), 3.85 (s, 3H, Ar-OCH3), 2.10 (d, 1H, J ¼ 2.4 Hz, OH) 1.0 Hz, PhCHaHbOCHCH]CH), 4.98 (s, 2H, PhCH2O) ppm. 13C-
ppm. 13C NMR (CDCl3, 100 MHz): d ¼ 149.6 (s, Ar-C), 147.8 (s, NMR (CDCl3, 100 MHz): d ¼ 158.0 (s, Ar-C), 140.5 (s, Ar-C), 139.1
Ar-C), 138.4 (d, CH]CH2), 136.5 (s, Ar-C), 133.4 (s, Ar-C), 128.5 (s, Ar-C), 137.1 (s, Ar-C), 136.4 (s, Ar-C), 133.4 (d, Ar-CH), 132.1
(d, 2C, Ar-CH), 128.0 (d, Ar-CH), 127.6 (d, 2C, Ar-CH), 115.7 (d, (d, Ar-CH), 130.5 (d, Ar-CH), 128.5 (d, 2C, Ar-CH), 128.0 (d, Ar-
Ar-CH), 115.3 (t, CH]CH2), 113.1 (s, Ar-C), 112.9 (d, Ar-CH), CH–CH]CH-Ar), 127.8 (d, Ar-CH–CH]CH-Ar), 127.5 (d, Ar-
73.2 (d, Ar-CHOH), 71.1 (t, PhCH2), 56.2 (q, Ar-OCH3) ppm. CH), 127.4 (d, 2C, Ar-CH), 122.0 (d, Ar-CH), 121.1 (d, Ar-CH),
HR-MS (ESI+) m/z calculated for [C17H16BrO2]+ ¼ [(M + H)– 116.2 (d, Ar-CH), 114.8 (s, Ar-C), 113.3 (d, Ar-CH), 84.8 (d, Ph-
H2O]+: 331.0328; found 331.0334.
CHCH]CH), 72.8 (t, Ph-CH2OCHCH]CH) 70.1 (t, PhCH2O)
1-(6-Bromo-1,3-benzodioxol-5-yl)prop-2-en-1-ol (2f). GP-1 was ppm. HR-MS (ESI+): m/z calculated for [C23H1879BrO]+ ¼ [(M +
carried out and the product 2f (2.0 g, 80%) was furnished as a H)–H2O]+: 389.0536; found 389.0545 and [C23H1881BrO]+ ¼ [(M +
colorless viscous liquid. [TLC control Rf(1f) ¼ 0.60, Rf(2f) ¼ 0.50 H)–H2O]+: 391.0515; found 391.0529.
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1-[(E)-2-(2-Bromo-5-methoxyphenyl)vinyl]-1,3-dihydro-2-benzo
RSC Advances
and 6.8 Hz, Ar-H), 7.31–7.24 (m, 4H, Ar-H), 7.20 (dd, 1H, J ¼ 8.3
and 2.4 Hz, Ar-H), 7.08 (s, 1H, J ¼ 9.3 Hz, Ar-H), 7.03 (s, 1H, J ¼ 9.3
Hz, Ar-H), 7.00 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.02 (dd, 1H, J ¼
15.6 and 7.8 Hz, ArCH]CH), 5.78 [d, 1H, J ¼ 7.8 Hz, PhCH(O)
CH]CH], 5.23 (dd, 1H, J ¼ 12.2 and 2.4 Hz, PhCHaHb-
OCHCH]CH), 5.13 (d, 1H, J ¼ 12.2 Hz, PhCHaHbOCHCH]CH),
5.06 (s, 2H, PhCH2O) 3.86 (s, 3H, Ar-OCH3) ppm. 13C-NMR
(CDCl3, 100 MHz): d ¼ 150.2 (s, Ar-C), 147.7 (s, Ar-C), 140.8 (s,
Ar-C), 139.2 (s, Ar-C), 136.5 (s, Ar-C), 130.6 (d, Ar-CH–CH]CH-Ar),
129.9 (d, Ar-CH–CH]CH-Ar), 128.6 (d, 2C, Ar-CH), 128.4 (s, Ar-C),
128.1 (d, Ar-CH), 127.8 (d, Ar-CH), 127.6 (d, 2C, Ar-CH), 127.5 (d,
Ar-CH), 122.1 (d, Ar-CH), 121.1 (d, Ar-CH), 115.8 (d, Ar-CH), 115.2
(s, Ar-C), 112.1 (d, Ar-CH), 85.2 (d, Ph-CHCH]CH), 72.9 (t, Ph-
CH2OCHCH]CH), 71.3 (t, PhCH2O), 56.2 (q, Ar-OCH3) ppm. HR-
MS (ESI+): m/z calculated for [C24H22BrO3]+ ¼ [M + H]+: 437.0747;
found 437.0735 and [C24H2281BrO3]+ ¼ [M + H]+: 439.0726; found
439.0732.
furan (6ac). GP-2 was carried out and the product 6ac (80 mg,
48%) was furnished as a pale brown viscous liquid. [TLC control
(petroleum ether/ethyl acetate 95 : 5, Rf(1a) ¼ 0.75, Rf(2c) ¼ 0.35
and Rf(6ac) ¼ 0.50 UV detection)]. IR (MIR-ATR, 4000–600
cmꢀ1): nmax ¼ 2959, 2929, 1592, 1571, 1464, 1287, 1236, 1161,
1014, 802, 754, 733, 599 cmꢀ1. 1H-NMR (CDCl3, 400 MHz): d ¼
7.35 (d, 1H, J ¼ 8.8 Hz, Ar-H), 7.30–7.05 (m, 4H, Ar-H), 7.01 (d,
1H, J ¼ 15.5 Hz, ArCH]CH), 6.97 (d, 1H, J ¼ 2.2 Hz, Ar-H), 6.62
(dd, 1H, J ¼ 8.7 and 3.0 Hz, Ar-H), 6.13 (dd, 1H, J ¼ 15.5 and 7.5
Hz, ArCH]CH), 5.74 [d, 1H, J ¼ 7.5 Hz, PhCH(O)CH]CH], 5.16
(dd, 1H, J ¼ 12.3 and 2.2 Hz, PhCHaHbOCHCH]CH), 5.08 (d,
1H, J ¼ 12.3 Hz, PhCHaHbOCHCH]CH), 3.68 (s, 3H, Ar-OCH3)
ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 158.9 (s, Ar-C), 140.5 (s,
Ar-C), 139.1 (s, Ar-C), 140.0 (s, Ar-C), 133.4 (d, Ar-CH), 132.0 (d,
Ar-CH), 130.7 (d, Ar-CH), 127.8 (d, Ar-CH–CH]CH-Ar), 127.5 (d,
Ar-CH–CH]CH-Ar), 122.0 (d, Ar-CH), 121.1 (d, Ar-CH), 115.7 (d,
Ar-CH), 114.5 (s, Ar-C), 112.0 (d, Ar-CH), 84.9 (d, Ph-CHCH]CH),
72.9 (t, Ph-CH2OCHCH]CH), 55.4 (q, Ar-OCH3) ppm. HR-MS
(ESI+): m/z calculated for [C17H14BrO]+ ¼ [(M + H)–H2O]+:
5-Bromo-6-[(E)-2-(1,3-dihydro-2-benzofuran-1-yl)vinyl]-1,3-
benzodioxole (6af). GP-2 was carried out and the product 6af (90
mg, 52%) was furnished as a pale yellow viscous liquid. [TLC
control (petroleum ether/ethyl acetate 90 : 10, Rf(1a) ¼ 0.80,
Rf(2f) ¼ 0.30 and Rf(6af) ¼ 0.65 UV detection)]. IR (MIR-ATR,
4000–600 cmꢀ1): nmax ¼ 2901, 2852, 1502, 1474, 1412, 1247,
1229, 1116, 1034, 978, 961, 933, 863, 838, 750 cmꢀ1.1H-NMR
(CDCl3, 400 MHz): d ¼ 7.35–7.23 (m, 3H, Ar-H), 7.19 (dd, 1H, J
¼ 8.3 and 2.4 Hz, Ar-H), 7.03 (d, 1H, J ¼ 15.6 Hz, ArCH]CH),
6.99 (d, 2H, J ¼ 2.4 Hz, Ar-H), 6.07 (dd, 1H, J ¼ 15.5 and 7.8 Hz,
ArCH]CH), 5.94 (s, 2H, OCH2O), 5.78 [d, 1H, J ¼ 7.8 Hz,
PhCH(O)CH]CH], 5.22 (dd, 1H, J ¼ 12.2 and 2.4 Hz, PhCHa-
313.0223; found 313.0212, [C17H1481BrO]+
¼
[(M + H)–
H2O]+:315.0202; found 315.0189 and [C17H19BrNO2]+ ¼ [M +
NH4]+: 348.0594; found 348.0587.
1-{(E)-2-[5-(Benzyloxy)-2-bromo-4-methoxyphenyl]vinyl}-1,3-
dihydro-2-benzofuran (6ad). GP-2 was carried out and the
product 6ad (92 mg, 42%) was furnished as a brown viscous
liquid. [TLC control (petroleum ether/ethyl acetate 90 : 10,
Rf(1a) ¼ 0.80, Rf(2d) ¼ 0.20 and Rf(6ad) ¼ 0.30 UV detection)]. IR
(MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2918, 2850, 1595, 1502, 1461,
1385, 1260, 1200, 1166, 1024, 861, 750, 697 cmꢀ1 1H-NMR
.
HbOCHCH]CH), 5.13 (d, 1H,
J
¼
12.2 Hz, PhCHaHb-
OCHCH]CH) ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 148.1 (s,
Ar-C), 147.6 (s, Ar-C), 140.7 (s, Ar-C), 139.1 (s, Ar-C), 130.5 (d, Ar-
CH–CH]CH-Ar), 130.3 (d, Ar-CH–CH]CH-Ar), 129.6 (s, Ar-C),
127.8 (d, Ar-CH), 127.4 (d, Ar-CH), 122.0 (d, Ar-CH), 121.1 (d,
Ar-CH), 115.0 (s, Ar-C), 112.6 (d, Ar-CH), 106.4 (d, Ar-CH),
101.7 (d, Ar-CH), 85.0 (d, Ph-CHCH]CH), 72.8 (t, Ph-CH2-
OCHCH]CH) ppm. HR-MS (ESI+): m/z calculated for
[C17H13BrNaO3]+ ¼ [M + Na]+: 366.9940; found 366.9938 and
[C17H1381BrNaO3]+ ¼ [M + Na]+: 368.9920; found 368.9918.
1-[(E)-2-(2-Bromo-4,5-dimethoxyphenyl)vinyl]-1,3-dihydro-2-
benzofuran (6ag). GP-2 was carried out and the product 6ag (78
mg, 43%) was furnished as a yellow viscous liquid. [TLC control
(petroleum ether/ethyl acetate 90 : 10, Rf(1a) ¼ 0.80, Rf(2g) ¼
0.15 and Rf(6ag) ¼ 0.30 UV detection)]. IR (MIR-ATR, 4000–600
cmꢀ1): nmax ¼ 2928, 2847, 1502, 1462, 1439, 1380, 1256, 1160,
(CDCl3, 400 MHz): d ¼ 7.43 (d, 2H, J ¼ 7.3 Hz, Ar-H), 7.38 (dd,
2H, J ¼ 7.3 and 6.8 Hz, Ar-H), 7.35–7.25 (m, 4H, Ar-H), 7.22 (dd,
1H, J ¼ 7.8 and 2.0 Hz, Ar-H), 7.06 (s, 1H, Ar-H), 7.04 (s, 1H, Ar-H),
7.03 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.13 (dd, 1H, J ¼ 15.6 and
7.8 Hz, ArCH]CH), 5.81 [d, 1H, J ¼ 7.8 Hz, PhCH(O)CH]CH],
5.25 (dd, 1H, J ¼ 12.2 and 2.4 Hz, PhCHaHbOCHCH]CH), 5.14
(d, 1H, J ¼ 12.2 Hz, PhCHaHbOCHCH]CH), 5.10 (s, 2H,
PhCH2O) 3.83 (s, 3H, Ar-OCH3) ppm. 13C-NMR (CDCl3, 100 MHz):
d ¼ 149.1 (s, Ar-C), 148.6 (s, Ar-C), 140.7 (s, Ar-C), 139.2 (s, Ar-C),
136.2 (s, Ar-C), 130.7 (d, Ar-CH–CH]CH-Ar), 130.0 (d, Ar-CH–
CH]CH-Ar), 128.8 (s, Ar-C), 128.6 (d, 2C, Ar-CH), 128.1 (d, Ar-
CH), 127.8 (d, Ar-CH), 127.5 (d, Ar-CH), 127.4 (d, 2C, Ar-CH),
122.1 (d, Ar-CH), 121.1 (d, Ar-CH), 117.6 (d, Ar-CH), 114.4 (s,
Ar-C), 109.6 (d, Ar-CH), 85.2 (d, Ph-CHCH]CH), 72.8 (t, Ph-
CH2OCHCH]CH), 71.1 (t, PhCH2O), 56.1 (q, Ar-OCH3) ppm. HR-
MS (ESI+): m/z calculated for [C24H21BrNaO3]+ ¼ [M + Na]+:
459.0566; found 459.0583 and [C24H21BrNaO3]+ ¼ [M + Na]+:
461.0546; found 461.0561.
1-{(E)-2-[4-(Benzyloxy)-2-bromo-5-methoxyphenyl]vinyl}-1,3-
dihydro-2-benzofuran (6ae). GP-2 was carried out and the
product 6ae (100 mg, 45%) was furnished as a brown viscous
liquid. [TLC control (petroleum ether/ethyl acetate 90 : 10,
Rf(1a) ¼ 0.80, Rf(2e) ¼ 0.20 and Rf(6ae) ¼ 0.35 UV detection)]. IR
(MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2957, 2920, 2851, 1503, 1462,
1441, 1379, 1261, 1206, 1163, 1026, 743 cmꢀ1. 1H-NMR (CDCl3,
400 MHz): d ¼ 7.40 (d, 2H, J ¼ 6.8 Hz, Ar-H), 7.34 (dd, 2H, J ¼ 7.3
1
1024, 751 cmꢀ1. H-NMR (CDCl3, 400 MHz): d ¼ 7.30–7.15 (m,
4H, Ar-H), 7.00 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.99 (s, 1H, Ar-
H), 6.98 (s, 1H, Ar-H), 6.10 (dd, 1H, J ¼ 15.6 and 7.8 Hz,
ArCH]CH), 5.78 [d, 1H, J ¼ 7.8 Hz, PhCH(O)CH]CH], 5.21 (dd,
1H, J ¼ 12.2 and 2.4 Hz, PhCHaHbOCHCH]CH), 5.13 (d, 1H, J ¼
12.2 Hz, PhCHaHbOCHCH]CH), 3.83 (s, 3H, Ar-OCH3), 3.81 (s,
3H, Ar-OCH3) ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 149.4 (s, Ar-
C), 148.4 (s, Ar-C), 140.6 (s, Ar-C), 139.1 (s, Ar-C), 130.6 (d, Ar-CH–
CH]CH-Ar), 129.8 (d, Ar-CH–CH]CH-Ar), 128.2 (s, Ar-C), 127.7
(d, Ar-CH), 127.4 (d, Ar-CH), 122.0 (d, Ar-CH), 121.0 (d, Ar-CH),
115.2 (d, Ar-CH), 114.5 (s, Ar-C), 109.0 (d, Ar-CH), 85.2 (d, Ph-
CHCH]CH), 72.8 (t, Ph-CH2OCHCH]CH), 56.0 (q, Ar-OCH3),
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56.9 (q, Ar-OCH3) ppm. HR-MS (ESI+): m/z calculated for detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2923, 2852,
[C18H17BrNaO3]+ ¼ [M + Na]+: 383.0253; found 383.0254.
1600, 1502, 1455, 1439, 1380, 1259, 1163, 1026, 737, 697 cmꢀ1
.
1-[(E)-2-(2-Bromo-3,4,5-trimethoxyphenyl)vinyl]-1,3-dihydro-2- 1H-NMR (CDCl3, 400 MHz): d ¼ 7.50–7.20 (m, 10H, Ar-H), 7.09
benzofuran (6ah). GP-2 was carried out and the product 6ah (90 (s, 1H, Ar-H), 7.05 (d, 1H, J ¼ 7.8 Hz, Ar-H), 7.03 (s, 1H, Ar-H),
mg, 46%) was furnished as a yellow viscous liquid. [TLC control 6.98 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.91 (dd, 1H, J ¼ 8.3
(petroleum ether/ethyl acetate 90 : 10, Rf(1a) ¼ 0.80, Rf(2h) ¼ and 2.0 Hz, Ar-H), 6.86 (d, 1H, J ¼ 2.0 Hz, Ar-H), 6.09 (dd, 1H, J ¼
0.10 and Rf(6ah) ¼ 0.25 UV detection)]. IR (MIR-ATR, 4000–600 15.6 and 7.8 Hz, ArCH]CH), 5.74 [d, 1H, J ¼ 7.8 Hz, ArCH(O)
cmꢀ1): nmax ¼ 2923, 2851, 1559, 1480, 1426, 1391, 1325, 1201, CH]CH], 5.17 (dd, 1H, J ¼ 12.2 and 2.0 Hz, ArCHaHbOCHCH]
1166, 1106, 1009, 926, 753 cmꢀ1. 1H-NMR (CDCl3, 400 MHz): d ¼ CH), 5.10 (d, 1H, J ¼ 12.2 Hz, ArCHaHbOCHCH]CH), 5.07 (s,
7.45–7.15 (m, 4H, Ar-H), 7.10 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 2H, PhCH2O), 5.07 (s, 2H, PhCH2O), 3.83 (s, 3H, Ar-OCH3) ppm.
6.87 (s, 1H, Ar-H), 6.13 (dd, 1H, J ¼ 15.6 and 7.8 Hz, ArCH]CH), 13C-NMR (CDCl3, 100 MHz): d ¼ 159.1 (s, Ar-C), 150.2 (s, Ar-C),
5.81 [d, 1H, J ¼ 7.8 Hz, PhCH(O)CH]CH], 5.23 (dd, 1H, J ¼ 12.2 148.6 (s, Ar-C), 140.9 (s, Ar-C), 136.8 (s, Ar-C), 136.2 (s, Ar-C),
and 2.4 Hz, PhCHaHbOCHCH]CH), 5.14 (d, 1H, J ¼ 12.2 Hz, 133.1 (s, Ar-C), 130.5 (d, Ar-CH–CH]CH-Ar), 130.2 (d, Ar-CH–
PhCHaHbOCHCH]CH), 3.88 (s, 3H, Ar-OCH3), 3.87 (s, 3H, Ar- CH]CH-Ar), 128.7 (d, 2C, Ar-CH), 128.6 (d, 2C, Ar-CH), 128.1 (s,
OCH3), 3.82 (s, 3H, Ar-OCH3) ppm. 13C-NMR (CDCl3, 100 MHz): Ar-C), 128.0 (d, 2C, Ar-CH), 127.4 (d, 2C, Ar-CH), 127.4 (d, 2C, Ar-
d ¼ 152.7 (s, Ar-C), 150.8 (s, Ar-C), 143.0 (s, Ar-C), 140.6 (s, Ar-C), CH), 122.9 (d, Ar-CH), 117.5 (d, Ar-CH), 114.6 (s, Ar-C), 114.4 (d, Ar-
139.1 (s, Ar-C), 131.9 (s, Ar-C), 131.2 (d, Ar-CH–CH]CH-Ar), CH), 109.5 (d, Ar-CH), 107.3 (d, Ar-CH), 84.8 (d, Ar-CHCH]CH),
130.9 (d, Ar-CH–CH]CH-Ar), 127.8 (d, Ar-CH), 127.5 (d, Ar-CH), 72.7 (t, Ar-CH2OCHCH]CH), 71.1 (t, PhCH2O), 70.3 (t, PhCH2O),
122.1 (d, Ar-CH), 121.1 (d, Ar-CH), 110.8 (s, Ar-C), 105.6 (d, 56.1 (s, 3H, Ar-OCH3) ppm. HR-MS (ESI+): m/z calculated for
Ar-CH), 85.1 (d, Ph-CHCH]CH), 72.9 (t, Ph-CH2OCHCH]CH), [C31H28BrO4]+ ¼ [M + H]+: 543.1165; found 543.1142 and
61.1 (q, Ar-OCH3), 61.0 (q, Ar-OCH3), 56.1 (q, Ar-OCH3) ppm. HR- [C31H2881BrO4]+ ¼ [M + H]+: 545.1145; found 545.1126, [C31H27-
MS (ESI+): m/z calculated for [C19H18BrO3]+ ¼ [(M + H)–H2O]+: BrNaO4]+ ¼ [M + Na]+: 565.0985; found 565.0962 and [C31H27
81-
373.0434; found 373.0416 and [C19H1881BrO3]+ ¼ [(M + H)–H2O]+: BrNaO4]+ ¼ [M + Na]+: 567.0964; found 567.0987.
375.0413; found 375.0401.
5-(Benzyloxy)-1-[(E)-2-(2-bromo-4,5-dimethoxyphenyl)vinyl]-1,3-
5-(Benzyloxy)-1-{(E)-2-[5-(benzyloxy)-2-bromo-4-methoxy phenyl]- dihydro-2-benzofuran (6bg). GP-2 was carried out and the
vinyl}-1,3-dihydro-2-benzofuran (6bd). GP-2 was carried out and product 6bg (108 mg, 47%) was furnished as a brown viscous
the product 6bd (111 mg, 41%) was furnished as a yellow liquid. [TLC control (petroleum ether/ethyl acetate 90 : 10,
viscous liquid. [TLC control (petroleum ether/ethyl acetate Rf(1b) ¼ 0.70, Rf(2g) ¼ 0.15 and Rf(6bg) ¼ 0.40 UV detection)]. IR
90 : 10, Rf(1b) ¼ 0.70, Rf(2d) ¼ 0.30 and Rf(6bd) ¼ 0.50 UV (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2922, 2851, 1600, 1503, 1462,
detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2956, 2922, 1439, 1259, 1162, 1027, 801, 737, 697 cmꢀ1. 1H-NMR (CDCl3, 400
2852, 1600, 1500, 1455, 1383, 1260, 1166, 1025, 737, 697 cmꢀ1
.
MHz): d ¼ 7.42 (dd, 2H, J ¼ 8.3 and 1.5 Hz, Ar-H), 7.38 (ddd, 2H,
1H-NMR (CDCl3, 400 MHz): d ¼ 7.50–7.25 (m, 10H, Ar-H), 7.11 J ¼ 8.3, 5.8 and 1.5 Hz, Ar-H), 7.33 (ddd, 1H, J ¼ 8.3, 5.8 and 1.5
(d, 1H, J ¼ 7.8 Hz, Ar-H), 7.06 (s, 1H, Ar-H), 7.05 (d, 1H, J ¼ 8.3 Hz, Ar-H), 7.11 (d, 1H, J ¼ 8.3 Hz, Ar-H), 7.02 (d, 1H, J ¼ 15.6 Hz,
Hz, Ar-H), 7.00 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.92 (d, 1H, J ¼ ArCH]CH), 7.01 (s, 1H, Ar-H), 7.00 (s, 1H, Ar-H), 5.91 (dd, 1H, J
7.8 Hz, Ar-H), 6.87 (s, 1H, Ar-H), 6.10 (dd, 1H, J ¼ 15.6 and 7.8 ¼ 8.3 and 2.4 Hz, Ar-H), 6.86 (d, 1H, J ¼ 2.0 Hz, Ar-H), 6.09 (dd,
Hz, ArCH]CH), 5.75 [d, 1H, J ¼ 7.8 Hz, ArCH(O)CH]CH], 5.18 1H, J ¼ 15.6 and 7.8 Hz, ArCH]CH), 5.75 [d, 1H, J ¼ 7.8 Hz,
(dd, 1H, J ¼ 12.7 and 2.0 Hz, ArCHaHbOCHCH]CH), 5.12 (d, ArCH(O)CH]CH], 5.18 (dd, 1H, J ¼ 12.2 and 2.4 Hz, ArCHaHb-
1H, J ¼ 12.7 Hz, ArCHaHbOCHCH]CH), 5.10 (s, 2H, PhCH2O), OCHCH]CH), 5.09 (d, 1H, J ¼ 12.2 Hz, ArCHaHbOCHCH]CH),
5.08 (s, 2H, PhCH2O), 3.83 (s, 3H, Ar-OCH3) ppm. 13C-NMR 5.07 (s, 2H, PhCH2O), 3.86 (s, 3H, Ar-OCH3), 3.83 (s, 3H, Ar-
(CDCl3, 100 MHz): d ¼ 159.1 (s, Ar-C), 149.1 (s, Ar-C), 148.6 (s, OCH3) ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 159.1 (s, Ar-C),
Ar-C), 140.9 (s, Ar-C), 136.8 (s, Ar-C), 136.2 (s, Ar-C), 133.0 (s, Ar- 149.4 (s, Ar-C), 148.5 (s, Ar-C), 140.9 (s, Ar-C), 136.8 (s, Ar-C),
C), 130.4 (d, Ar-CH–CH]CH-Ar), 130.3 (d, Ar-CH–CH]CH-Ar), 133.1 (s, Ar-C), 130.4 (d, Ar-CH–CH]CH-Ar), 130.1 (d, Ar-CH–
128.8 (s, Ar-C), 128.6 (d, 3C, Ar-CH), 128.1 (d, Ar-CH), 128.0 (d, CH]CH-Ar), 128.5 (d, 2C, Ar-CH), 128.3 (s, Ar-C), 128.0 (d, Ar-
Ar-CH), 127.4 (d, 5C, Ar-CH), 122.9 (d, Ar-CH), 117.6 (d, Ar-CH), CH), 127.4 (d, 2C, Ar-CH), 122.9 (d, Ar-CH), 115.2 (d, Ar-CH),
114.6 (d, Ar-CH), 114.3 (s, Ar-C), 109.6 (d, Ar-CH), 107.3 (d, Ar- 114.6 (d, Ar-CH), 114.5 (s, Ar-C), 109.1 (d, Ar-CH), 107.3 (d, Ar-
CH), 84.9 (d, Ar-CHCH]CH), 72.7 (t, Ar-CH2OCHCH]CH), CH), 84.9 (d, Ar-CHCH]CH), 72.7 (t, Ar-CH2OCHCH]CH),
71.1 (t, PhCH2O), 70.3 (t, PhCH2O), 56.0 (q, Ar-OCH3) ppm. HR- 70.3 (t, PhCH2O), 56.1 (q, Ar-OCH3), 55.9 (q, Ar-OCH3) ppm. HR-
MS (ESI+): m/z calculated for [C31H28BrO4]+ ¼ [M + H]+: MS (ESI+): m/z calculated for [C25H24BrO4]+ ¼ [M + H]+: 467.0852;
543.1165; found 543.1140 and [C31H2881BrO4]+ ¼ [M + H]+: found 467.0824 and [C25H2481BrO4]+ ¼ [M + H]+: 469.0832; found
545.1145; found 545.1130, [C31H27BrNaO4]+ ¼ [M + Na]+: 469.0817, [C25H23BrNaO4]+ ¼ [M + Na]+: 489.0672; found
565.0985; found 565.0959 and [C31H2781BrNaO4]+ ¼ [M + Na]+: 489.0646 and [C25H2381BrNaO4]+ ¼ [M + Na]+: 491.0651; found
567.0964; found 567.0977.
5-(Benzyloxy)-1-{(E)-2-[4-(benzyloxy)-2-bromo-5-methoxy phenyl]-
491.0649.
1-[(E)-2-(2-Bromophenyl)vinyl]-5-methoxy-1,3-dihydro-2-benzo
vinyl}-1,3-dihydro-2-benzofuran (6be). GP-2 was carried out and furan (6ca). GP-2 was carried out and the product 6ca (79 mg,
the product 6be (119 mg, 44%) was furnished as a brown 48%) was furnished as a yellow viscous liquid. [TLC control
viscous liquid. [TLC control (petroleum ether/ethyl acetate (petroleum ether/ethyl acetate 90 : 10, Rf(1c) ¼ 0.70, Rf(2a) ¼
90 : 10, Rf(1b) ¼ 0.70, Rf(2e) ¼ 0.30 and Rf(6be) ¼ 0.55 UV 0.40 and Rf(6ca) ¼ 0.50 UV detection)]. IR (MIR-ATR, 4000–600
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cmꢀ1): nmax ¼ 2956, 2924, 2854, 1610, 1493, 1466, 1275, 1117, C), 130.4 (d, Ar-CH–CH]CH-Ar), 130.3 (d, Ar-CH–CH]CH-Ar),
1025, 821, 748, 665 cmꢀ1. 1H-NMR (CDCl3, 400 MHz): d ¼ 7.54 128.8 (s, Ar-C), 128.6 (d, 2C, Ar-CH), 128.1 (d, Ar-CH), 127.4 (d,
(d, 1H, J ¼ 7.8 and 1.5 Hz, Ar-H), 7.51 (d, 1H, J ¼ 7.8 and 1.5 Hz, 2C, Ar-CH), 122.9 (d, Ar-CH), 117.5 (d, Ar-CH), 114.3 (s, Ar-C),
Ar-H), 7.22 (dd, 1H, J ¼ 7.8 and 1.5 Hz, Ar-H), 7.15–7.00 (m, 3H, 113.7 (d, Ar-CH), 109.5 (d, Ar-CH), 106.2 (d, Ar-CH), 84.9 (d,
Ar-H and ArCH]CH), 6.83 (dd, 1H, J ¼ 8.3 and 2.4 Hz, Ar-H), Ar-CHCH]CH), 72.7 (t, Ar-CH2OCHCH]CH), 71.1 (t,
6.79 (d, 1H, J ¼ 2.4 Hz, Ar-H), 6.19 (dd, 1H, J ¼ 15.6 and 7.8 PhCH2O), 56.1 (q, Ar-OCH3), 55.5 (q, Ar-OCH3) ppm. HR-MS
Hz, ArCH]CH), 5.75 [d, 1H, J ¼ 7.8 Hz, ArCH(O)CH]CH], 5.18 (ESI+): m/z calculated for [C25H24BrO4]+ ¼ [M + H]+: 467.0852;
(dd, 1H, J ¼ 12.2 and 2.4 Hz, ArCHaHbOCHCH]CH), 5.09 (d, found 467.0826 and [C25H2481BrO4]+ ¼ [M + H]+: 469.0832;
1H, J ¼ 12.2 Hz, ArCHaHbOCHCH]CH), 3.81 (s, 3H, Ar-OCH3) found 469.0812.
ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 160.0 (s, Ar-C), 140.9 (s,
5-Bromo-6-[(E)-2-(5-methoxy-1,3-dihydro-2-benzofuran-1-yl)-
Ar-C), 136.4 (s, Ar-C), 132.9 (d, Ar-CH), 132.7 (s, Ar-C), 132.4 (d, Ar- vinyl]-1,3-benzodioxole (6cf). GP-2 was carried out and the
CH), 130.3 (d, Ar-CH–CH]CH-Ar), 129.0 (d, Ar-CH–CH]CH-Ar), product 6cf (80 mg, 43%) was furnished as a pale yellow liquid.
127.4 (d, Ar-CH), 127.3 (d, Ar-CH), 123.8 (s, Ar-C), 122.8 (d, Ar-CH), [TLC control (petroleum ether/ethyl acetate 90 : 10, Rf(1c) ¼
113.7 (d, Ar-CH), 106.3 (d, Ar-CH), 84.7 (d, Ar-CHCH]CH), 72.8 (t, 0.70, Rf(2f) ¼ 0.50 and Rf(6cf) ¼ 0.55 UV detection)]. IR (MIR-
Ar-CH2OCHCH]CH), 55.6 (q, Ar-OCH3) ppm. HR-MS (ESI+) m/z ATR, 4000–600 cmꢀ1): nmax ¼ 2921, 2852, 1605, 1500, 1474,
calculated for [C17H15BrNaO2]+ ¼ [M + Na]: 353.0148; found 1235, 1106, 1036, 932, 870, 822 cmꢀ1
.
1H-NMR (CDCl3, 400
353.0164.
MHz): d ¼ 7.07 (d, 1H, J ¼ 8.3 Hz, Ar-H), 6.99 (s, 2H, Ar-H), 6.98
1-[(E)-2-(2-Bromo-5-methoxyphenyl)vinyl]-5-methoxy-1,3-di hydro- (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.82 (dd, 1H, J ¼ 8.3 and 2.4 Hz,
2-benzofuran (6cc). GP-2 was carried out and the product 6cc (71 Ar-H), 6.77 (d, 1H, J ¼ 2.4 Hz, Ar-H), 6.04 (dd, 1H, J ¼ 15.6 and
mg, 45%) was furnished as a brown viscous liquid. [TLC control 7.8 Hz, ArCH]CH), 5.94 (s, 2H, OCH2O), 5.72 [d, 1H, J ¼ 7.8 Hz,
(petroleum ether/ethyl acetate 90 : 10, Rf(1c) ¼ 0.70, Rf(2c) ¼ ArCH(O)CH]CH], 5.17 (dd, 1H, J ¼ 12.2 and 2.4 Hz, ArCHa-
0.50 and Rf(6cc) ¼ 0.60 UV detection)]. IR (MIR-ATR, 4000–600 HbOCHCH]CH), 5.08 (d, 1H, J ¼ 12.2 Hz, ArCHaHbOCHCH]
cmꢀ1): nmax ¼ 2957, 2922, 2852, 1594, 1465, 1284, 1241, 1016, CH), 3.81 (s, 3H, Ar-OCH3) ppm. 13C-NMR (CDCl3, 100 MHz): d
1
804 cmꢀ1. H-NMR (CDCl3, 400 MHz): d ¼ 7.42 (d, 1H, J ¼ 8.8 ¼ 160.0 (s, Ar-C), 148.1 (s, Ar-C), 147.6 (s, Ar-C), 140.8 (s, Ar-C),
Hz, Ar-H), d ¼ 7.10 (d, 1H, J ¼ 8.3 Hz, Ar-H), d ¼ 7.04 (d, 1H, J ¼ 132.7 (s, Ar-C), 130.6 (d, Ar-CH–CH]CH-Ar), 130.2 (d, Ar-CH–
3.3 Hz, Ar-H), 7.02 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.83 (dd, 1H, CH]CH-Ar), 129.7 (s, Ar-C), 122.7 (d, Ar-CH), 115.0 (s, Ar-C),
J ¼ 8.3 and 1.9 Hz, Ar-H), 6.79 (d, 1H, J ¼ 1.9 Hz, Ar-H), 6.69 (dd, 113.7 (d, Ar-CH), 112.6 (d, Ar-CH), 106.4 (d, Ar-CH), 106.2 (d,
1H, J ¼ 8.8 and 2.9 Hz, Ar-H), 6.18 (dd, 1H, J ¼ 15.6 and 7.8 Hz, Ar-CH), 101.7 (t, OCH2O), 84.7 (d, Ar-CHCH]CH), 72.7 (t, Ar-
ArCH]CH), 5.75 [d, 1H, J ¼ 7.8 Hz, ArCH(O)CH]CH], 5.19 (dd, CH2OCHCH]CH), 55.5 (q, Ar-OCH3) ppm. HR-MS (ESI+): m/z
1H, J ¼ 12.2 and 2.4 Hz, ArCHaHbOCHCH]CH), 5.10 (d, 1H, J ¼ calculated for [C18H16BrO4]+ ¼ [M + H]+: 375.0226; found
12.2 Hz, ArCHaHbOCHCH]CH), 3.81 (s, 3H, Ar-OCH3), 3.76 (s, 375.0212 and [C18H1681BrO4]+ ¼ [M + H]+: 377.0206; found
3H, Ar-OCH3) ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 160.0 (s, Ar- 377.0189.
C), 158.9 (s, Ar-C), 140.9 (s, Ar-C), 137.1 (s, Ar-C), 133.5 (d, Ar-
1-[(E)-2-(2-Bromo-3,4,5-trimethoxyphenyl)vinyl]-5-methoxy-1,3-
CH), 132.6 (s, Ar-C), 132.4 (d, Ar-CH–CH]CH-Ar), 130.5 (d, Ar- dihydro-2-benzofuran (6ch). GP-2 was carried out and the
CH–CH]CH-Ar), 122.8 (d, Ar-CH), 115.7 (d, Ar-CH), 114.6 (s, Ar- product 6ch (86 mg, 41%) was furnished as a pale yellow viscous
C), 113.7 (d, Ar-CH), 112.0 (d, Ar-CH), 106.3 (d, Ar-CH), 84.7 (d, liquid. [TLC control (petroleum ether/ethyl acetate 80 : 20,
Ar-CHCH]CH), 72.8 (t, Ar-CH2OCHCH]CH), 55.6 (s, Ar- Rf(1c) ¼ 0.95, Rf(2h) ¼ 0.25 and Rf(6ch) ¼ 0.45 UV detection)]. IR
OCH3), 55.5 (s, Ar-OCH3) ppm. HR-MS (ESI+) m/z calculated for (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2923, 2852, 1563, 1481, 1463,
[C18H16BrO2]+ ¼ [M + Na]: 343.0328; found 343.0314.
1427, 1392, 1326, 1274, 1200, 1165, 1107, 1031, 1011, 926, 813
1-{(E)-2-[5-(Benzyloxy)-2-bromo-4-methoxyphenyl]vinyl}-5-methoxy- cmꢀ1. 1H-NMR (CDCl3, 400 MHz): d ¼ 7.08 (d, 1H, J ¼ 8.8 Hz, Ar-
1,3-dihydro-2-benzofuran (6cd). GP-2 was carried out and the H), 7.06 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.86 (s, 1H, Ar-H), 6.83
product 6cd (103 mg, 44%) was furnished as a brown viscous (dd, 1H, J ¼ 8.3 and 2.4 Hz, Ar-H), 6.78 (d, 1H, J ¼ 2.4 Hz, Ar-H),
liquid. [TLC control (petroleum ether/ethyl acetate 90 : 10, 6.10 (dd, 1H, J ¼ 15.6 and 7.8 Hz, ArCH]CH), 5.75 (d, 1H, J ¼
Rf(1c) ¼ 0.70, Rf(2d) ¼ 0.30 and Rf(6cd) ¼ 0.40 UV detection)]. IR 7.8 Hz, ArCH(O)CH]CH), 5.18 (dd, 1H, J ¼ 12.2 and 2.4 Hz,
(MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2924, 2853, 1597, 1497, 1465, ArCHaHbOCHCH]CH), 5.09 (d, 1H, J ¼ 12.2 Hz, ArCHaHb-
1261, 1201, 1166, 1117, 1029, 813, 743, 698 cmꢀ1 1H-NMR OCHCH]CH), 3.88 (s, 3H, Ar-OCH3), 3.87 (s, 3H, Ar-OCH3),
.
(CDCl3, 400 MHz): d ¼ 7.42 (d, 2H, J ¼ 7.3 Hz, Ar-H), 7.37 (dd, 3.82 (s, 3H, Ar-OCH3), 3.80 (s, 3H, Ar-OCH3) ppm. 13C-NMR
2H, J ¼ 7.8 and 7.3 Hz, Ar-H), 7.31 (t, 1H, J ¼ 7.3 Hz, Ar-H), 7.10 (CDCl3, 100 MHz): d ¼ 160.0 (s, Ar-C), 152.6 (s, Ar-C), 150.8 (s,
(d, 1H, J ¼ 8.3 Hz, Ar-H), 7.06 (s, 1H, Ar-H), 7.04 (s, 1H, Ar-H), Ar-C), 143.0 (s, Ar-C), 140.8 (s, Ar-C), 132.6 (s, Ar-C), 131.9 (s, Ar-
6.99 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.84 (dd, 1H, J ¼ 8.3 C), 131.5 (d, Ar-CH–CH]CH-Ar), 130.6 (d, Ar-CH–CH]CH-Ar),
and 2.0 Hz, Ar-H), 6.79 (d, 1H, J ¼ 2.0 Hz, Ar-H), 6.10 (dd, 1H, J ¼ 122.8 (d, Ar-CH), 113.7 (d, Ar-CH), 110.8 (s, Ar-C), 106.2 (d, Ar-
15.6 and 7.8 Hz, ArCH]CH), 5.75 [d, 1H, J ¼ 7.8 Hz, ArCH(O) CH), 105.6 (d, Ar-CH), 84.7 (d, Ar-CHCH]CH), 72.7 (t, Ar-CH2-
CH]CH], 5.19 (dd, 1H, J ¼ 12.2 and 2.4 Hz, ArCHaHbOCHCH] OCHCH]CH), 61.1 (q, Ar-OCH3), 60.9 (q, Ar-OCH3), 56.1 (q, Ar-
CH), 5.10 (s, 2H, PhCH2O), 5.09 (d, 1H, J ¼ 12.2 Hz, ArCHaHb- OCH3), 55.5 (q, Ar-OCH3) ppm. HR-MS (ESI+): m/z calculated for
OCHCH]CH), 3.83 (s, 3H, Ar-OCH3), 3.81 (s, 3H, Ar-OCH3) [C20H21BrNaO5]+ ¼ [M + Na]+: 443.0465; found 443.0448.
ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 159.9 (s, Ar-C), 149.1 (s,
5-{(E)-2-[5-(Benzyloxy)-2-bromophenyl]vinyl}-5,7-dihydrofuro [3,4-f]-
Ar-C), 148.6 (s, Ar-C), 140.9 (s, Ar-C), 136.2 (s, Ar-C), 132.7 (s, Ar- [1,3]benzodioxole (6). GP-2 was carried out and the product 6
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(92 mg, 41%) was furnished as pale yellow viscous liquid. [TLC 1380, 1261, 1208, 1163, 1035, 937, 860, 736, 698, 665 cmꢀ1. 1H-
control (petroleum ether/ethyl acetate 90 : 10, Rf(1f) ¼ 0.30, NMR (CDCl3, 400 MHz): d ¼ 7.00 (s, 2H, Ar-H), 6.98 (d, 1H, J ¼
Rf(2b) ¼ 0.45 and Rf(6) ¼ 0.40 UV detection)]. IR (MIR-ATR, 15.6 Hz, ArCH]CH), 6.67 (s, 1H, Ar-H), 6.63 (s, 1H, Ar-H), 6.06
4000–600 cmꢀ1): nmax ¼ 2920, 2851, 1591, 1501, 1464, 1378, (dd, 1H, J ¼ 15.6 and 7.8 Hz, ArCH]CH), 5.97 (d, 1H, J ¼ 2.9 Hz,
1278, 1239, 1173, 1122, 1039, 939, 851, 737, 698 cmꢀ1. 1H-NMR OCHaHbO), 5.96 (d, 1H, J ¼ 2.9 Hz, OCHaHbO), 5.69 (d, 1H, J ¼
(CDCl3, 400 MHz): d ¼ 7.50–7.27 (m, 6H, Ar-H), 7.14 (d, 1H, J ¼ 7.8 Hz, ArCH(O)CH]CH), 5.11 (dd, 1H, J ¼ 11.7 and 2.0 Hz,
2.9 Hz, Ar-H), 7.01 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.76 (dd, 1H, ArCHaHbOCHCH]CH), 5.02 (dd, 1H, J ¼ 11.7 and 2.0 Hz,
J ¼ 8.8 and 2.9 Hz, Ar-H), 6.68 (s, 1H, Ar-H), 6.62 (s, 1H, Ar-H), ArCHaHbOCHCH]CH), 3.86 (s, 3H, Ar-OCH3), 3.83 (s, 3H, Ar-
6.14 (dd, 1H, J ¼ 15.6 and 7.8 Hz, ArCH]CH), 5.97 (d, 1H, J ¼ OCH3) ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 149.5 (s, Ar-C),
2.9 Hz, OCHaHbO), 5.97 (d, 1H, J ¼ 2.9 Hz, OCHaHbO), 5.70 (d, 148.5 (s, Ar-C), 148.0 (s, Ar-C), 147.7 (s, Ar-C), 133.6 (s, Ar-C),
1H, J ¼ 7.8 Hz, ArCH(O)CH]CH), 5.12 (dd, 1H, J ¼ 11.7 and 2.9 131.9 (s, Ar-C), 130.7 (d, Ar-CH–CH]CH-Ar), 130.0 (d, Ar-CH–
Hz, ArCHaHbOCHCH]CH), 5.04 (d, 1H, J ¼ 11.7 Hz, ArCHa- CH]CH-Ar), 128.2 (s, Ar-C), 115.3 (d, Ar-CH), 114.6 (s, Ar-C),
HbOCHCH]CH), 5.01 (s, 2H, PhCH2O) ppm. 13C-NMR (CDCl3, 109.1 (d, Ar-CH), 102.7 (d, Ar-CH), 101.6 (d, Ar-CH), 101.5 (t,
100 MHz): d ¼ 158.1 (s, Ar-C), 148.0 (s, Ar-C), 147.7 (s, Ar-C), OCH2O), 85.2 (d, Ar-CHCH]CH), 72.8 (t, Ar-CH2OCHCH]CH),
137.1 (s, Ar-C), 136.4 (s, Ar-C), 133.5 (d, Ar-CH–CH]CH-Ar), 56.1 (q, Ar-OCH3), 56.0 (q, Ar-OCH3) ppm. HR-MS (ESI+): m/z
133.4 (s, Ar-C), 132.3 (d, Ar-CH–CH]CH-Ar), 131.9 (s, Ar-C), calculated for [C19H17BrNaO5]+ ¼ [M + Na]+: 427.0152; found
130.5 (d, Ar-CH), 128.6 (d, 2C, Ar-CH), 128.1 (d, Ar-CH), 127.4 427.0127 and [C19H1781BrNaO5]+ ¼ [M + Na]+: 429.0137; found
(d, 2C, Ar-CH), 116.3 (d, Ar-CH), 114.8 (s, Ar-C), 113.3 (d, Ar-CH), 429.0121, HR-MS (ESI+) m/z calculated for [C19H18BrO5]+ ¼ [M +
102.6 (d, Ar-CH), 101.6 (d, Ar-CH), 101.5 (t, OCH2O), 84.9 (d, Ar- H]+: 405.0332; found 405.0304 and [C19H1881BrO5]+ ¼ [M + H]+:
CHCH]CH), 72.9 (t, Ar-CH2OCHCH]CH), 70.2 (t, PhCH2O) 407.0312; found 407.0294.
ppm. HR-MS (ESI+): m/z calculated for [C24H19BrNaO4]+ ¼ [M +
5-[(E)-2-(2-Bromo-3,4,5-trimethoxyphenyl)vinyl]-5,7-dihydro furo-
Na]+: 473.0359; found 473.0330 and [C24H1981BrNaO4]+ ¼ [M + [3,4-f][1,3]benzodioxole (6). GP-2 was carried out and the
Na]+: 475.0338; found 475.0317.
product 6 (98 mg, 45%) was furnished as a pale brown viscous
5-{(E)-2-[4-(Benzyloxy)-2-bromo-5-methoxyphenyl]vinyl}-5,7- liquid. [TLC control (petroleum ether/ethyl acetate 80 : 20, Rf(1f)
dihydrofuro[3,4-f][1,3]benzodioxole (6fe). GP-2 was carried out ¼ 0.70, Rf(2h) ¼ 0.20 and Rf(6) ¼ 0.40 UV detection)]. IR (MIR-
and the product 6fe (113 mg, 47%) was furnished as a brown ATR, 4000–600 cmꢀ1): nmax ¼ 2928, 2854, 1566, 1503, 1482,
viscous liquid. [TLC control (petroleum ether/ethyl acetate 1394, 1329, 1264, 1198, 1164, 1107, 1037, 1010, 934, 814, 739
80 : 20, Rf(1f) ¼ 0.70, Rf(2e) ¼ 0.30 and Rf(6fe) ¼ 0.50 UV cmꢀ1. 1H-NMR (CDCl3, 400 MHz): d ¼ 7.05 (d, 1H, J ¼ 15.6 Hz,
detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2956, 2924, ArCH]CH), 6.86 (s, 1H, Ar-H), 6.68 (s, 1H, Ar-H), 6.64 (s, 1H, Ar-
2853, 1598, 1502, 1439, 1259, 1162, 1033, 852, 803, 735, 698 H), 6.07 (dd, 1H, J ¼ 15.6 and 7.8 Hz, ArCH]CH), 5.96 (d, 1H, J
cmꢀ1. 1H-NMR (CDCl3, 400 MHz): d ¼ 7.41 (d, 2H, J ¼ 7.3 Hz, Ar- ¼ 2.9 Hz, OCHaHbO), 5.95 (d, 1H, J ¼ 2.9 Hz, OCHaHbO), 5.69 (d,
H), 7.34 (dd, 2H, J ¼ 7.8 and 7.3 Hz, Ar-H), 7.30 (t, 1H, J ¼ 7.3 Hz, 1H, J ¼ 7.8 Hz, ArCH(O)CH]CH), 5.11 (dd, 1H, J ¼ 11.7 and 2.9
Ar-H), 7.07 (s, 1H, Ar-H), 7.02 (s, 1H, Ar-H), 6.95 (d, 1H, J ¼ 15.6 Hz, ArCHaHbOCHCH]CH), 5.03 (dd, 1H, J ¼ 11.7 and 2.9 Hz,
Hz, ArCH]CH), 6.68 (s, 1H, Ar-H), 6.60 (s, 1H, Ar-H), 6.96 (dd, ArCHaHbOCHCH]CH), 3.88 (s, 3H, Ar-OCH3), 3.87 (s, 3H, Ar-
1H, J ¼ 15.6 and 7.8 Hz, ArCH]CH), 5.97 (s, 2H, OCH2O), 5.67 OCH3), 3.83 (s, 3H, Ar-OCH3) ppm. 13C-NMR (CDCl3, 100 MHz):
(d, 1H, J ¼ 7.8 Hz, ArCH(O)CH]CH), 5.11 (dd, 1H, J ¼ 11.7 and d ¼ 152.6 (s, Ar-C), 150.8 (s, Ar-C), 148.0 (s, Ar-C), 147.7 (s, Ar-C),
2.9 Hz, ArCHaHbOCHCH]CH), 5.07 (s, 2H, PhCH2O), 5.02 (dd, 143.0 (s, Ar-C), 133.4 (s, Ar-C), 131.9 (s, Ar-C), 131.8 (s, Ar-C),
1H, J ¼ 11.7 and 2.9 Hz, ArCHaHbOCHCH]CH), 3.85 (s, 3H, Ar- 131.3 (d, Ar-CH–CH]CH-Ar), 130.8 (d, Ar-CH–CH]CH-Ar),
OCH3) ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 150.2 (s, Ar-C), 110.8 (s, Ar-C), 105.6 (d, Ar-CH), 102.6 (d, Ar-CH), 101.6 (d, Ar-
148.0 (s, Ar-C), 147.6 (s, 2C, Ar-C), 136.5 (s, Ar-C), 133.6 (s, Ar- CH), 101.5 (t, OCH2O), 85.0 (d, Ar-CHCH]CH), 72.9 (t, Ar-
C), 131.9 (s, Ar-C), 130.5 (d, Ar-CH–CH]CH-Ar), 130.0 (d, Ar- CH2OCHCH]CH), 61.1 (q, Ar-OCH3), 60.9 (q, Ar-OCH3), 56.1 (q,
CH–CH]CH-Ar), 128.5 (d, 2C, Ar-CH), 128.3 (s, Ar-C), 128.0 (d, Ar-OCH3) ppm. HR-MS (ESI+): m/z calculated for [C20H19-
Ar-CH), 127.5 (d, 2C, Ar-CH), 115.7 (d, Ar-CH), 115.1 (s, Ar-C), BrNaO6]+ ¼ [M + Na]+: 457.0257; found 457.0257 and [C20
-
112.1 (d, Ar-CH), 102.6 (d, Ar-CH), 101.6 (d, Ar-CH), 101.5 (t, H1981BrNaO6]+ ¼ [M + Na]+: 459.0237; found 459.0236.
OCH2O), 85.1 (d, Ar-CHCH]CH), 72.8 (t, Ar-CH2OCHCH]CH),
1-{(E)-2-[5-(Benzyloxy)-2-bromo-4-methoxyphenyl]vinyl}-5,6-
71.2 (t, PhCH2O), 56.2 (q, Ar-OCH3) ppm. HR-MS (ESI+): m/z dimethoxy-1,3-dihydro-2-benzofuran (6gd). GP-2 was carried out
calculated for [C25H22BrO5]+ ¼ [M + H]+: 481.0645; found and the product 6gd (116 mg, 47%) was furnished as a brown
481.0615 and [C25H2281BrO5]+ ¼ [M + H]+: 483.0625; found viscous liquid. [TLC control (petroleum ether/ethyl acetate
483.0602, [C25H21BrNaO5]+ ¼ [M + Na]+: 503.0465; found 70 : 30, Rf(1g) ¼ 0.65, Rf(2d) ¼ 0.55 and Rf(6gd) ¼ 0.40 UV
503.0438 and [C25H21Br81NaO5]+ ¼ [M + Na]+: 505.0444; found detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2926, 2853,
505.0422.
1598, 1503, 1463, 1384, 1261, 1203, 1166, 1032, 859, 737, 698
5-[(E)-2-(2-Bromo-4,5-dimethoxyphenyl)vinyl]-5,7-dihydrofuro cmꢀ1. 1H-NMR (CDCl3, 400 MHz): d ¼ 7.41 (d, 2H, J ¼ 7.3 Hz, Ar-
[3,4-f][1,3]benzodioxole (6fg). GP-2 was carried out and the H), 7.36 (dd, 2H, J ¼ 7.8 and 7.3 Hz, Ar-H), 7.31 (t, 1H, J ¼ 7.3 Hz,
product 6fg (85 mg, 42%) was furnished as a pale yellow viscous Ar-H), 7.05 (s, 2H, Ar-H), 7.00 (d, 1H, J ¼ 15.6 Hz, ArCH]CH),
liquid. [TLC control (petroleum ether/ethyl acetate 80 : 20, Rf(1f) 6.77 (s, 1H, Ar-H), 6.69 (s, 1H, Ar-H), 6.10 (dd, 1H, J ¼ 15.6 and
¼ 0.70, Rf(2g) ¼ 0.30 and Rf(6fg) ¼ 0.55 UV detection)]. IR (MIR- 8.3 Hz, ArCH]CH), 5.75 (d, 1H, J ¼ 8.3 Hz, ArCH(O)CH]CH),
ATR, 4000–600 cmꢀ1): nmax ¼ 2924, 2852, 1600, 1503, 1473, 5.18 (dd, 1H, J ¼ 11.7 and 2.0 Hz, ArCHaHbOCHCH]CH), 5.10
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(s, 2H, PhCH2O), 5.07 (dd, 1H, J ¼ 11.2 and 2.9 Hz, ArCHaHb- (petroleum ether/ethyl acetate 70 : 30, Rf(3aj) ¼ 0.80, Rf(5aj) ¼
OCHCH]CH), 3.88 (s, 3H, Ar-OCH3), 3.86 (s, 3H, Ar-OCH3), 0.30 UV detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax
¼
3.83 (s, 3H, Ar-OCH3) ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 3320, 1597, 1489, 1461, 1244, 1023, 753 cmꢀ1. 1H-NMR (CDCl3,
149.3 (s, Ar-C), 149.1 (s, Ar-C), 149.0 (s, Ar-C), 148.6 (s, Ar-C), 400 MHz): d ¼ 7.39 (ddd, 2H, J ¼ 8.8, 7.8 and 1.5 Hz, Ar-H),
136.2 (s, Ar-C), 132.1 (s, Ar-C), 130.6 (s, Ar-C), 130.6 (d, Ar-CH– 7.32–7.10 (m, 4H, Ar-H), 6.99 (d, 1H, J ¼ 16.1 Hz, ArCH]
CH]CH-Ar), 130.2 (d, Ar-CH–CH]CH-Ar), 128.7 (s, Ar-C), 128.6 CH), 6.87 (dd, 1H, J ¼ 7.8 and 7.3 Hz, Ar-H), 6.82 (d, 1H, J ¼ 8.3
(d, 2C, Ar-CH), 128.1 (d, Ar-CH), 127.3 (d, 2C, Ar-CH), 117.5 (d, Ar- Hz, Ar-H), 6.43 (dd, 1H, J ¼ 16.1 and 5.9 Hz, ArCH]CH), 5.52
CH), 114.4 (s, Ar-C), 109.5 (d, Ar-CH), 104.9 (d, Ar-CH), 103.9 (d, [d, 1H, J ¼ 5.9 Hz, PhCH(OH)CH]CH], 4.66 (s, 2H, ArCH2OH),
Ar-CH), 85.6 (d, Ar-CHCH]CH), 73.0 (t, Ar-CH2OCHCH]CH), 3.77 (s, 3H, Ar-OCH3), 3.64 (br.s, 2H, 2 ꢂ OH) ppm. 13C-NMR
71.1 (t, PhCH2O), 56.2 (q, Ar-OCH3), 56.1 (q, Ar-OCH3), 56.0 (q, (CDCl3, 100 MHz): d ¼ 156.7 (s, Ar-C), 141.1 (s, Ar-C), 138.5
Ar-OCH3) ppm. HR-MS (ESI+): m/z calculated for [C26H25- (s, Ar-C), 131.0 (d, Ar-CH–CH]CH-Ar), 130.0 (d, Ar-CH), 128.8
BrNaO5]+
¼
[M +
Na]+: 519.0778; found 519.0753 and (d, Ar-CH–CH]CH-Ar), 128.3 (d, Ar-CH), 128.1 (d, Ar-CH),
[C26H2581BrNaO5]+ ¼ [M + Na]+: 521.0757; found 521.0735.
127.8 (d, Ar-CH), 127.0 (d, Ar-CH), 125.5 (s, Ar-C), 125.4 (d,
1-[(E)-2-(2-Bromo-4,5-dimethoxyphenyl)vinyl]-5,6-dimethoxy-1,3- Ar-CH), 120.6 (d, Ar-CH), 110.8 (d, Ar-CH), 73.2 (d, Ph-CHCH]
dihydro-2-benzofuran (6gg). GP-2 was carried out and the CH), 63.5 (t, Ph-CH2OH), 55.4 (q, Ar-OCH3) ppm. HR-MS (ESI+):
product 6gg (90 mg, 43%) was furnished as a brown viscous m/z calculated for [C17H19O3]+ ¼ [M + H]+: 271.1329; found
liquid. [TLC control (petroleum ether/ethyl acetate 70 : 30, Rf(1g) 271.1320.
¼ 0.65, Rf(2g) ¼ 0.45 and Rf(6gg) ¼ 0.35 UV detection)]. IR (MIR-
1-[(E)-2-(2-Methylphenyl)vinyl]-1,3-dihydro-2-benzofuran (6ai).
ATR, 4000–600 cmꢀ1): nmax ¼ 2924, 2852, 1600, 1504, 1462, 1264, GP-3 was carried out and the product 6ai (50 mg, 84%) was
1210, 1163, 1121, 1029, 863 cmꢀ1. 1H-NMR (CDCl3, 400 MHz): d furnished as a colorless viscous liquid. [TLC control (petroleum
¼ 7.02 (s, 1H, Ar-H), 7.01 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 7.00 (s, ether/ethyl acetate 95 : 5, Rf(5ai) ¼ 0.15, Rf(6ai) ¼ 0.80 UV
1H, Ar-H), 6.77 (s, 1H, Ar-H), 6.69 (s, 1H, Ar-H), 6.09 (dd, 1H, J ¼ detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2924, 2853,
15.6 and 7.8 Hz, ArCH]CH), 5.74 (d, 1H, J ¼ 7.8 Hz, ArCH(O) 1731, 1460, 1029, 965, 747, 697 cmꢀ1
.
1H-NMR (CDCl3, 400
CH]CH), 5.17 (dd, 1H, J ¼ 11.2 and 2.9 Hz, ArCHaHbOCHCH] MHz): d ¼ 7.45 (d, 1H, J ¼ 8.3 Hz, Ar-H), 7.36–7.25 (m, 3H, Ar-H),
CH), 5.07 (dd, 1H, J ¼ 11.2 and 2.9 Hz, ArCHaHbOCHCH]CH), 7.24–7.10 (m, 4H, Ar-H), 6.97 (d, 1H, J ¼ 15.6 Hz, ArCH]CH),
3.88 (s, 3H, Ar-OCH3), 3.86 (s, 6H, Ar-OCH3), 3.83 (s, 3H, Ar- 6.16 (dd, 1H, J ¼ 15.6 and 7.8 Hz, ArCH]CH), 5.79 [d, 1H, J ¼
OCH3) ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 149.5 (s, Ar-C), 7.8 Hz, PhCH(O)CH]CH], 5.23 (dd, 1H, J ¼ 12.2 and 2.4 Hz,
149.4 (s, Ar-C), 149.1 (s, Ar-C), 148.5 (s, Ar-C), 132.2 (s, Ar-C), PhCHaHbOCHCH]CH), 5.14 (d, 1H, J ¼ 12.2 Hz, PhCHaHb-
130.7 (s, Ar-C), 130.6 (d, Ar-CH–CH]CH-Ar), 130.1 (d, Ar-CH– OCHCH]CH), 2.39 (s, 3H, Ar-CH3) ppm. 13C-NMR (CDCl3, 100
CH]CH-Ar), 128.3 (s, Ar-C), 115.3 (d, Ar-CH), 114.6 (s, Ar-C), MHz): d ¼ 141.0 (s, Ar-C), 139.2 (s, Ar-C), 135.7 (s, Ar-C), 135.5 (s,
109.1 (d, Ar-CH), 105.0 (d, Ar-CH), 104.0 (d, Ar-CH), 85.6 (d, Ar-C), 130.3 (2 ꢂ d, 2C, Ar-CH–CH]CH-Ar and Ar-CH), 129.9 (d,
Ar-CHCH]CH), 73.0 (t, Ar-CH2OCHCH]CH), 56.2 (q, Ar- Ar-CH), 127.7 (2 ꢂ d, 2C, Ar-CH–CH]CH-Ar and Ar-CH), 127.4
OCH3), 56.1 (q, Ar-OCH3), 56.0 (q, Ar-OCH3), 55.9 (q, Ar-OCH3) (d, Ar-CH), 126.0 (d, Ar-CH), 125.9 (d, Ar-CH), 122.0 (d, Ar-CH),
ppm. HR-MS (ESI+): m/z calculated for [C20H21BrNaO5]+ ¼ [M + 121.1 (d, Ar-CH), 85.5 (d, Ph-CHCH]CH), 72.8 (t, Ph-CH2-
Na]+: 443.0465; found 443.0468.
(2E)-3-[2-(Hydroxymethyl)phenyl]-1-(2-methylphenyl)prop-2-en-
1-ol (5ai). GP-3 was carried out and the product 5ai (65 mg, 97%)
OCHCH]CH), 19.9 (q, Ar-CH3) ppm. HR-MS (ESI+): m/z calcu-
lated for [C17H16NaO]+ ¼ [M + Na]+: 259.1093; found 259.1099.
1-[(E)-2-(2-Methoxyphenyl)vinyl]-1,3-dihydro-2-benzofuran (6aj).
was furnished as a yellow colored viscous liquid. [TLC control GP-3 was carried out and the product 6aj (53 mg, 86%) was
(petroleum ether/ethyl acetate 70 : 30, Rf(3ai) ¼ 0.70, Rf(5ai) ¼ furnished as a colorless viscous liquid. [TLC control (petroleum
0.30 UV detection)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 3330, ether/ethyl acetate 95 : 5, Rf(5aj) ¼ 0.10, Rf(6aj) ¼ 0.70 UV detec-
1485, 1459, 1006, 967, 753, 564 cmꢀ1
.
1H-NMR (CDCl3, 400 tion)]. IR (MIR-ATR, 4000–600 cmꢀ1): nmax ¼ 2904, 2838, 1489,
MHz): d ¼ 7.52–7.46 (m, 1H, Ar-H), 7.44 (d, 1H, J ¼ 7.8 Hz, Ar-H), 1461, 1244, 1028, 749, 697 cmꢀ1. 1H-NMR (CDCl3, 400 MHz): d ¼
7.32–7.10 (m, 6H, Ar-H), 6.98 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 7.45 (dd, 1H, J ¼ 7.8 and 1.5 Hz, Ar-H), 7.36–7.15 (m, 5H, Ar-H),
6.21 (dd, 1H, J ¼ 15.6 and 5.9 Hz, ArCH]CH), 5.47 [d, 1H, J ¼ 7.09 (d, 1H, J ¼ 15.6 Hz, ArCH]CH), 6.91 (d, 1H, J ¼ 7.3 Hz,
5.9 Hz, PhCH(OH)CH]CH], 4.63 (d, 1H, J ¼ 12.2 Hz, PhCHa- Ar-H), 6.87 (d, 1H, J ¼ 7.3 Hz, Ar-H), 6.30 (dd, 1H, J ¼ 15.6 and 7.8
HbOH), 4.62 (d, 1H, J ¼ 12.2 Hz, PhCHaHbOH), 3.76 (br.s, 1H, Hz, ArCH]CH), 5.78 [d, 1H, J ¼ 7.8 Hz, PhCH(O)CH]CH], 5.23
OH), 3.29 (br.s, 1H, OH), 2.35 (s, 3H, Ar-CH3) ppm. 13C-NMR (dd, 1H, J ¼ 12.2 and 2.4 Hz, PhCHaHbOCHCH]CH), 5.13 (d, 1H,
(CDCl3, 100 MHz): d ¼ 140.4 (s, Ar-C), 137.5 (s, Ar-C), 135.8 (s, J ¼ 12.2 Hz, PhCHaHbOCHCH]CH), 3.86 (s, 3H, Ar-OCH3)
Ar-C), 135.2 (s, Ar-C), 133.2 (d, Ar-CH–CH]CH-Ar), 130.4 (d, Ar- ppm. 13C-NMR (CDCl3, 100 MHz): d ¼ 156.9 (s, Ar-C), 141.2 (s,
CH), 128.7 (d, Ar-CH–CH]CH-Ar), 128.1 (d, Ar-CH), 127.6 (d, Ar- Ar-C), 139.2 (s, Ar-C), 129.4 (d, Ar-CH–CH]CH-Ar), 128.9 (d, Ar-
CH), 127.5 (d, Ar-CH), 126.9 (d, Ar-CH), 126.2 (2 ꢂ d, 2C, Ar-CH), CH), 127.6 (d, Ar-CH–CH]CH-Ar), 127.4 (d, Ar-CH), 127.1 (d,
125.9 (d, Ar-CH), 71.4 (d, Ph-CHCH]CH), 63.1 (t, Ph-CH2OH), Ar-CH), 127.0 (d, Ar-CH), 125.4 (s, Ar-C), 122.1 (d, Ar-CH), 121.0
19.1 (q, Ar-CH3) ppm. HR-MS (ESI+): m/z calculated for (d, Ar-CH), 120.5 (d, Ar-CH), 110.8 (d, Ar-CH), 85.9 (d, Ph-
[C17H18NaO2]+ ¼ [M + Na]+: 277.1199; found 277.1197.
CHCH]CH), 72.7 (t, Ph-CH2OCHCH]CH), 55.4 (q, Ar-OCH3)
(2E)-3-[2-(Hydroxymethyl)phenyl]-1-(2-methoxyphenyl)prop-2-en- ppm. HR-MS (ESI+): m/z calculated for [C17H17O2]+ ¼ [M + H]+:
1-ol (5aj). GP-3 was carried out and the product 5aj (67 mg, 96%) 253.1223; found 253.1219.
was furnished as a colorless viscous liquid. [TLC control
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Conclusions
In summary, we have developed an efficient and practical
method for the direct synthesis of 1,3-dihydroisobenzofurans,
an important structural motif present in biologically active
natural or synthetic compounds. [Pd]-catalyzed controlled
intermolecular Mizoroki–Heck coupling and reduction were
performed sequentially. The direct treatment of the resultant
crude diol without further purication with BF3$Et2O gave 1,3-
dihydroisobenzofurans. Signicantly, the method enabled the
synthesis of 1,3-dihydroisobenzofurans with simple to electron
rich aromatic rings. Importantly, the protocol is also applicable
for a wide range of ortho substituted allylic alcohols. It is worth
mentioning that although the yields of the cyclic ether 1,3-
dihydroisobenzofurans are moderate, it actually represents the
overall yield of three individual reactions.
Acknowledgements
Council of Scientic and Industrial Research [(CSIR), 02(0018)/
11/EMR-II], New Delhi, is gratefully acknowledged. JK and PN
thank CSIR, New Delhi, for awarding the research fellowship.
Notes and references
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